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Krill meal enhances performance of feed pellets through concentration-dependent prolongation of consumption by Pacific white shrimp, Litopenaeus vannamei
... Additionally, ethological studies have employed various methods to study shrimp feeding behaviour in the laboratory, contributing to the development of diets and feeding management protocols (for review, see [5,76]). These methods generally include direct visual observations of the feeding behaviour of isolated or small groups of shrimp [77][78][79][80][81][82][83][84][85], as well as video recordings conducted in translucent tanks with one or multiple cameras, or even in Y-maze tanks [4,59,75]. Despite the difficulties posed by shrimp anatomy/habit and the intensive observational work required, studies in this area form the knowledge base regarding important mechanisms of detection and chemical stimulation involved in feeding activity, as well as various behavioural repertoires associated with the repetitive movement of cephalothorax appendages [5]. ...
... The evaluation of feed formulations and/or the inclusion of additives (i.e., chemoattractants and food stimulants) to improve attractiveness and palatability has typically been conducted in Y-maze or compartmentalised tanks, through the observation of shrimp preferences and feeding behaviour in the laboratory [78,80,85]. The use of PAM for this purpose was first tested by Soares et al. [32] in assessing the effect of additives (krill meal, krill oil and fish hydrolysate) in practical soy-based diets on the feeding behaviour of L. vannamei. ...
... Feeding management is one of the areas most directly benefitted by a better understanding of shrimp behaviour [5,12,13,107]. Ethological studies have significantly contributed to the current knowledge on different aspects of shrimp feeding behaviour, such as feeding frequencies [79,82], circadian rhythm [84,108,109], food restriction and moulting cycle [4], stocking density [98], pellet size [75,81] and, on a larger scale, the inclusion of additives in diets [59,77,78,80,83,85,[110][111][112][113][114][115][116]. Although most of these studies have been conducted with visual observations under laboratory conditions, new technologies such as computer vision and PAM have been successfully applied in shrimp behavioural studies, as also reviewed by De Tailly et al. [12], Reis et al. [14] and Li et al. [10]. ...
The use of passive acoustic monitoring (PAM) has recently been integrated with other noninvasive ethological methodologies to enhance the understanding of shrimp feeding behaviour, as their mandibles emit click sounds during food intake. This review aims to compile recent advances and various applications of PAM in assessing shrimp feeding behaviour under controlled laboratory and farm conditions. It includes a description of key concepts, terms and general methodologies in the field of bioacoustics to facilitate understanding of acoustic characterisation, specific methodologies and the main uses of PAM in shrimp research. Among the primary contributions of PAM in laboratory studies are acoustic characterisation of clicks and mandibular structures associated with their emission for different species; variations in acoustic click parameters related to animal size, feed texture and pellet size; and effects on feeding behaviour caused by shrimp size, stocking density and specific characteristics of artificial diets (texture, formulations, additives and pellet sizes). Finally, future perspectives and recommendations for laboratory studies using PAM are provided. The review highlights the contribution of PAM, which, allied with other ethological methodologies, emerges as a novel tool for researching shrimp behaviour and optimising feed management in aquaculture.
... Most of the published studies have evaluated KRM in diets that combined high levels of plant and/or animal proteins with low inclusions of FML [7,9,10,31] or in diets that were not thoroughly balanced for essential nutrients [7,9,23,31,32]. In the latter case, KRM is generally added to the diets as a supplementary ingredient or as an FML protein replacement. ...
... Most of the published studies have evaluated KRM in diets that combined high levels of plant and/or animal proteins with low inclusions of FML [7,9,10,31] or in diets that were not thoroughly balanced for essential nutrients [7,9,23,31,32]. In the latter case, KRM is generally added to the diets as a supplementary ingredient or as an FML protein replacement. Even if formulas are designed to be isonitrogenous and/or isolipidic, these approaches will likely elevate the levels of EAAs, EFAs, and other nutrients if not appropriately balanced. ...
... Other studies have found that KRM can successfully stimulate behavioral feeding activity in P. vannamei when included at a dietary level of 10 to 30 g kg −1 in FML-challenged diets [8,31]. Nevertheless, the effectiveness of feeding effectors varies [8,10,31], as does their minimum concentration needed to boost feed attractability and palatability [7,8,31]. This is likely because the amount of stimulatory compounds (free amino acids, nucleotides, peptides) diverges widely among ingredients [10]. ...
Shrimp feeds depend on high levels of digestible protein and essential amino acids, which can be sourced from various commercially available feed ingredients. Marine proteins can be used to partially fulfill the requirements of these and other important nutrients. Their utilization is further influenced by their palatability and growth-promoting effect. However, marine ingredients can significantly drive costs in feed formulation depending on the type and dietary inclusion level. This study aimed to determine the minimum dietary level of fish meal (FML) and krill meal (KRM) and their mix ratio to elicit feed intake and growth performance in juvenile Penaeus vannamei. Ten diets were formulated with graded FML (90, 60, 30 g kg−1) in combination with 15, 30, and 45 g kg−1 KRM and a control diet with 120 g kg−1 FML. Shrimp (1.28 ± 0.08 g body weight, BW) were stocked in seventy 1-m3 tanks (135 animals m−2), and after 88 days, their growth performance was determined. Feed preference was assessed through two-by-two comparisons in twenty 0.5 m3 tanks over four weeks. No significant differences in survival (93.9 ± 4.5%), gained yield (1235 ± 92 g m−2), and feed conversion ratio (1.47 ± 0.09) were observed. Diets with 60 g kg−1 FML led to faster growth and higher feed intake than 30, 90, and 120 g kg−1 FML. Shrimp on 30 g kg−1 FML diets had the lowest BW, especially with 30–15 (FML-KRM) and 30–30 diets. Diets with 90 g kg−1 FML outperformed 30 g kg−1 FML. The control diet delivered a higher shrimp BW than diets 30-15 and 30-30, showing similar results to other diets except 60–15. Feed preference was influenced by KRM inclusion, with 15 g kg−1 KRM resulting in higher apparent feed intake than 30 and 45 g kg−1. The findings indicate that FML can be effectively reduced by up to 75% when combined with lower levels of KRM. This corresponds with the industry’s ongoing trend to achieve greater sustainability and cost efficiency through the reduced utilization of critical resources.
... Uno de los aspectos que mayor atención ha recibido en los estudios para la creación de técnicas de cultivo de estos langostinos ha sido la determinación de los requerimientos nutricionales, ya que la alimentación puede representar hasta el 60% de los costos de producción acuícola, considerándose de gran importancia el desarrollo de dietas artificiales que aseguren un buen crecimiento, supervivencia y calidad nutricional de los organismos a un bajo costo (Espinosa-Chaurand et al. 2012;Yamasaki-Granados et al. 2013, Vega-Villasante et al. 2014. Con base en lo anterior, la realización de análisis de composición químico proximal para la evaluación de la calidad de las dietas formuladas según los requerimientos nutricionales de cada etapa de vida de la especie es crucial para el desarrollo de las biotecnologías acuícolas, ya que de éste aspecto dependen en buena parte los efectos fisiológicos que tendrán los alimentos suministrados en los organismos cultivados (Derby et al. 2016;Hua et al. 2019). Asimismo, la calidad nutricional de estos últimos al momento de la comercialización es consecuencia de, entre otros factores, la calidad nutrimental de las dietas que se les proporciona a lo largo de toda la fase de cultivo, se requiere de la elaboración de protocolos alimenticios acuícolas con insumos (macro y microingredientes) de buena calidad a fin de coadyuvar en la producción de alimentos de alto valor nutricional (Hernández-Vergara et al. 2003;Martínez-Córdova & Martínez-Porchas, 2014). ...
... En la última década, ante la reducción de la inclusión de harinas de pescado en dietas acuícolas, se ha buscado optimizar la composición bioquímica de estos productos a fin de garantizar que satisfagan con los requerimientos nutricionales de las especies de interés acuícola (Cozzolino et al. 2005;Derby et al. 2016;FAO, 2020). Debido a esto, la realización de análisis químico-proximales para evaluar la calidad físico-química de las harinas de pescado ha cobrado una relevancia cada vez mayor, así como también la evaluación de posibles sustitutos a estos ingredientes de origen marino (Cabello et al. 2013;Ween et al. 2018). ...
... Tailandia, Vietnam, EUA y Noruega(FAO, 2020;Gozzer-Wuest et al. 2022).Actualmente, los aceites y harinas de pescado son los principales componentes que se utilizan en la producción industrial de dietas de alta calidad para peces, camarones y langostinos, lo cual se debe a que su perfil bioquímico tiene un óptimo equilibrio entre proteínas (aminoácidos) y lípidos de cadena larga(Gaxiola & Cuzon, 2014;Hodar et al. 2020). En consecuencia, se considera que las harinas de pescado son una excelente fuente de proteína altamente digerible, además de que mejora la eficiencia nutrimental de los alimentos balanceados gracias a su buena palatabilidad, y a que permiten un rápido y eficiente desarrollo de los organismos cultivados(Derby et al. 2016;Bandara, 2018). A causa de que las fuentes de proteína vegetal no presentan la misma atractabilidad y digestibilidad en peces carnívoros y crustáceos que los aminoácidos y ácidos grasos de las harinas y aceites de pescado, su sustitución total en la formulación de dietas para estas especies parece inviable en el corto plazo Hua et al. 2019). ...
... Most of the feeding effectors identified for marine shrimp are found in protein-rich ingredients of marine origin including fish meal, fish solubles, fish hydrolysate, squid head offal meal, squid liver meal, shrimp head offal meal, krill meal, krill hydrolysate, and bivalve meals from clams, oysters and mussels Grey et al., 2009;Smith et al., 2005;Guillaume et al., 1989;Suarez et al., 1985;Cruz--Ricque et al., 1987;Suresh and Nates, 2011;Derby et al., 2016). Incorporation of these ingredients and/or compounds into shrimp diets have long been used to enhance shrimp feeding responses at levels ranging from 0.5 up to 5% of the diet (as-is basis) (Hartati and Briggs, 1993). ...
... They are rich in low molecular weight compounds capable of eliciting shrimp feeding responses which significantly enhance feed attractability and palatability (Suresh and Nates, 2011). This ultimately leads to longer and increased feed consumption which becomes particularly relevant in fish meal-challenged feeds (Suresh and Nates, 2011;Derby et al., 2016). These marine proteins are included at low dietary levels, between 0.5% and 5% (as-is basis), sufficient to prompt positive feeding behavioral responses in shrimp depending on attractant type and diet composition . ...
... ranked krill meal as the best feeding effector and growth enhancer for L. vannamei among six other marine ingredients, i.e., salmon meal, squid meal, shrimp head meal, shrimp meal, squid liver meal, and sardine hydrolysate. Also, krill meal has been found to increase feed palatability in marine shrimp by prolonging the feeding bout and the amount of feed eaten (Derby et al., 2016). In feeds formulated with 20 % poultry meal and no fishmeal, 3% Table 5 Selected marine raw materials and their reported effects on the feeding and growth of farmed penaeid shrimp. ...
Feed formulations for marine shrimp have adapted to the stagnant fish meal supplies and increasing prices by progressively moving to alternative protein sources such as plant and rendered animal by-products. This review presents the current challenges on the use of conventional and non-conventional feed sources, with a focus on solving the economical, sustainability and performance challenges of low-fish meal diets. As a case study, this review shows that krill meal can be included to address some of these concerns, such as missing essential nutrients, lower attractability/palatability and antinutritional factors that suppress feeding stimulus, reduce nutrient bioavailability and hence increase production costs. The combination of protein, nutrients and feed attractants of krill meal is useful to address the disadvantages of alternative feed ingredients which range from being poorer feeding effectors to having lower bioavailability of nutrients. It can therefore be used as a formulation tool to decrease the reliance on fish meal, which opens the way for alternative ingredients that improve the cost efficiency and sustainability of feeds.
... Despite positive results on growth performance, the use of this alternative protein sources at high dietary levels frequently raises concerns about poor attractability and palatability of these diets to shrimp (Tantikitti, 2014;Jannathulla et al., 2021). The inclusion of chemoattractants, especially those derived from marine aquatic animals, such as meals and hydrolysates of krill, squid and fish have been used to improve chemosensory characteristics and feed intake of low-fish meal diets (Lee and Meyers, 1996;Smith et al., 2005;Grey et al., 2009;Suresh et al., 2011;Derby et al., 2016;Yuan et al., 2020;Soares et al., 2021;Jannathulla et al., 2021). The chemoattractants promote fast feed detection and improve palatability, stimulating shrimp feeding behavior (Nunes et al., 2019;Jannathulla et al., 2021). ...
... The ventral location of mouthparts appendages and benthic feeding behavior of shrimp, coupled with some laboratory or farming conditions, such as water depth and clarity, type of tanks or ponds, stocking densities and shrimp sizes, could restrict visual observations or video recordings of their feeding activity (Reis et al., 2022). Nevertheless, most of the current knowledge on the contribution of chemoattractants to enhance the attractability and palatability in shrimp diets has been based on direct observation or video of feeding behavior under specially designed laboratory conditions analysis (Sanchez et al., 2005;Nunes et al., 2006;Ahamad-Ali et al., 2007;Suresh et al., 2011;Derby et al., 2016;Bardera et al., 2019aBardera et al., , 2021. In addition to behavioral responses, some studies used simple measurements of feed intake, feed conversion rates ratios and growth performance to evaluate the attractability of ingredients in shrimp diets (Hartati and Briggs, 1993;Córdova-Murueta and García-Carreño, 2002;Nunes et al., 2011Nunes et al., , 2020Hernández et al., 2011;Yuan et al., 2020). ...
... Sabry-Neto et al. (2017) were able to stimulate L. vannamei feed intake working with an even lower inclusion level of krill meal (10 g/kg) in all-plant diets. Additionally, the study of Derby et al. (2016) showed that krill meal added to a basal diet (270 g/kg of poultry protein and high inclusion of plant proteins) enhanced the palatability of L. vannamei in a concentration-dependent fashion up to 60 g/kg. Nunes et al. (2019) using a basal diet with low fish meal level (30 g/kg) and a high dietary inclusion of plant ingredients, found that supplementation with 30 g/Kg of krill meal increase feed attractiveness and stimulation than the same dose of several other chemoattractants, including salmon meals and squid meal. ...
The inclusion of chemoattractants has been investigated to improve the attractability and palatability of plant-based shrimp diets. A more recent approach utilizes passive acoustic monitoring (PAM) to record the sounds (clicks) emitted by shrimp during feeding activity allowing the identification of behavioral responses related to the diets. In the present study we automatically identified click signals in PAM recordings at sampling frequency of 192 kHz. This methodology was applied to evaluate the efficiency of three chemoattractants (krill meal, squid meal and fish hydrolysate) added to a basal all-plant diet on the acoustic feeding behavior and food consumption of naive (without acclimation) and non-naive (acclimated to the diets) Litopenaeus vannamei. Five diets were used: basal all-plant diet (AP, negative control) and its modifications to contain 20 g/Kg of krill meal (AP+KM), 20 g/Kg of squid meal (AP+SM) and 40 g/Kg of fish hydrolysate (AP+FH); a diet with 120 g/Kg fishmeal (FM) was used as a positive control. Ten shrimp (6.8 ± 0.6 g; mean ± SD) were stocked per aquarium (70 L) in a clear water recirculation system (30 aquaria, five diets with six replicates). The food consumption and acoustic activity were evaluated simultaneously in each aquarium over a 30-min period during two consecutive days for each trial, naive and non-naive shrimp. Strong positive relationships (r = 0.78 to 0.81; P < 0.001) were found between food consumption and total number of clicks emitted by naive and non-naive shrimp. Overall, the inclusion of the chemoattractants to the plant-based diet had a positive effect improving acoustic feeding behavior and food consumption for naive and non-naive L. vannamei. In particular, the response of non-naive shrimp to chemoattractants was markedly increased, and the highest clicking activity was attained by using krill meal (AP+KM), followed by fish hydrolysate (AP+FH). The new analytical method proved to be a useful J o u r n a l P r e-p r o o f 3 alternative approach for studying shrimp feeding behavior, also indicating the potential of PAM to forecast feed intake and improve efficiency of feed management.
... Therefore, supplementing chemoattractants is likely to enhance growth in the cultured species. Derby et al. (2016) reported that chemoattractants influence the different phases of feeding behaviour in aquatic species, in particular shrimp. By stimulating the appetitive phases of arousal, search initiation and locating the feed, chemoattractants enhance the attractability and palatability, by which they not only increase the feed consumption rate and growth, but also reduce the waste production during culture operation. ...
... In addition, deficiency of certain essential nutrients, higher content of fibre fractions and the presence of anti-nutrients would also partly be a reason for the diminished effect of plant-based ingredients (Jannathulla et al., 2018). It is reported that the use of chemoattractants in feeds helps to stimulate the animals' behavioural pattern of feeding by promoting feed detection towards the source (Derby et al., 2016). Mendoza et al. (1997) reported that the supplementation of chemoattractants shortened the time period to detect feed by the animals thereby increasing likelihood of ingestion. ...
... This clearly indicates that krill meal is not only an effective feed attractant but also a potent feeding stimulant compared to other chemoattractants. This corroborates with the findings of Derby et al. (2016), who reported that searching, probing and grabbing behaviour was very high in P. vannamei fed very low concentration of aqueous extract of krill meal (13.3 µg ml -1 ). However, there is no clear-cut information regarding the growth enhancing effect of chemoattractants, in particular those mainly derived from marine sources. ...
Aquaculture serves as a sustainable source of good quality wholesome food and major input is feed. In recent years, considerable quantities of plant sources have been attempted for inclusion in shrimp feed, due to high demand and high cost of fishmeal. Plant-based ingredients are in general poor in attractability and palatability to aquatic species compared to marine sources. It is desirable to develop an economical and nutritious feed that is attractive and palatable for ensuring reduction of feed wastage. Chemoattractants nowadays are unavoidable in commercial shrimp feeds and are included either individually or in combination. The present review revealed that the various marine sources, in particular krill meal would be more effective for aquatic species, compared to those derived from vegetable origin and chemical compounds. In addition to acting as a feed attractant, marine sources serve as a potential fishmeal substitute due to their rich nutritional composition. However, certain biogenic amines present in these marine-based ingredients need to be examined before their use, since these amines when present in high concentrations reduces feed intake by producing undesirable odour. Use of a combination of chemoattractants would give a better effect, rather than using them individually and compounds from plant origin have limited beneficial effects. The present review concludes that incorporation of chemoattractants would be beneficial in formulation of enriched and economical feeds with better attractability and palatability. The selection of suitable attractant and their supplementation at correct proportion is significantly more important to avoid undesirable effects in cultured shrimp. Further field-based research is needed to predict the actual effects of chemoattractants on farmed shrimp and to provide a sustainable base for the expansion of shrimp aquaculture sector, by reducing feed wastage.
... The latest results of soybean-based diets on shrimp growth performance are promising both under in-laboratory Roy et al., 2009;Sookying and Davis, 2012;Zhou et al., 2015;Galkanda-Arachchige et al., 2019;Guo et al., 2020) and ponds systems (Roy et al., 2009;Sookying and Davis, 2012;Jescovitch et al., 2018;Ullman et al., 2019a;Ullman et al., 2019b;Reis et al., 2020). However, the addition of feeding effectors (chemoattractants, feeding incitants and stimulants) in diets with high percentage of plant material has been suggested to improve feed detection and consumption by stimulating shrimp chemosensory systems (Lee and Meyers, 1996;Sanchez et al., 2005;Smith et al., 2005;Nunes et al., 2006;Suresh et al., 2011;Derby et al., 2016). Such stimulation can also contribute to the minimalization of leaching of nutrients and feed waste caused by the intensive food manipulation and selective feeding behavior of shrimp (Lee and Meyers, 1996;Sanchez et al., 2005). ...
... The enhancement of desirable chemosensory characteristics of soybean-based shrimp diets has been attained by adding low percentages of ingredients (1 to 6% of meals, oils and hydrolysates) derived from aquatic animals, such as of krill, squid and fish (Lee and Meyers, 1996;Smith et al., 2005;Grey et al., 2009;Derby et al., 2016). These ingredients are rich in chemical signal compounds, particularly amino acids and nucleotides, that are readily detectable by the chemosensory systems of crustaceans (Derby and Sorensen, 2008;Suresh et al., 2011). ...
... These ingredients are rich in chemical signal compounds, particularly amino acids and nucleotides, that are readily detectable by the chemosensory systems of crustaceans (Derby and Sorensen, 2008;Suresh et al., 2011). Additionally, shrimp response may also be influenced by the inclusion levels of different feeding effectors in the diets Nunes et al., 2006;Derby et al., 2016). Derby et al. (2016) observed an increase in the feed consumption of Litopenaeus vannamei by increasing the inclusion levels of krill meal from 1 to 6%. ...
The inclusion of feeding effectors in plant-based diets is a strategy to accelerate feed detection and consumption by shrimp. This study evaluated the effect of krill meal (KM), krill oil (KO) and fish hydrolysate (FH) addition to a soybean-based diet on feeding behavior and growth of Litopenaeus vannamei. Ten diets (360 g/kg crude protein) were formulated including FH, KM and KO at 0, 10, 20 and 40 g/kg levels named as: Basal (0); FH10 (10 g/kg fish hydrolysate), FH20 (20 g/kg fish hydrolysate), FH40 (40 g/kg fish hydrolysate); KM1 (10 g/kg krill meal), KM20 (20 g/kg krill meal), KM40 (40 g/kg krill meal); KO10 (10 g/kg krill oil), KO20 (20 g/kg krill oil) and KO40 (40 g/kg krill oil). A growth trial was performed using twenty shrimp (0.15 ± 0.01 g) stocked per 100 L glass aquaria (four replicates/diet) in an indoor clear water recirculation system (4.2 ppt, 28 °C). Animals were fed the experimental diets four times a day for six weeks. At the end of the trial all animals were counted and weighted. Following, 300 animals (3.93 ± 0.35 g) were aleatory selected and transferred back to the system (10 shrimp/aquaria). Three replicates were used per treatment (ten diets) for feed intake and acoustic feeding behavior analysis. The food consumption and feeding activity sounds were recorded simultaneously in 30 min intervals during five consecutive days. All feeding effectors at the inclusion levels tested significantly increased L. vannamei food consumption and the passive acoustic monitoring indicated that shrimp ate faster and for longer periods of time. Food consumption was significantly higher in the treatments KM20, KM40 and KO40. The addition of feeding effectors also enhanced shrimp growth performance and significantly better values of biomass, final weight, and food conversion ratio were observed in the treatment KM40. Weight gain (%) was significantly improved only in shrimp offered KM40, KO20 and KO40 diets. It is concluded that KM, KO and FH can stimulate food consumption of soy-based diet by L. vannamei from 10 g/kg addition while the amount of food consumed and growth has been shown to be in general dose-related, although in a different way, for each type of feeding effector.
... Marine invertebrate meals have been shown to stimulate greater and longer feeding in shrimp (Simon et al., 2020;Derby et al., 2016;Nunes et al., 2006). Simon et al. (2020) investigated the effects of krill and squid meals and microbial biomass (Novacq™) on growth, feed efficiency, nutrient retention and gut microbiota in the shrimp, Penaeus monodon. ...
... Communal feed intake of juvenile shrimp was measured for each of the four diets over three periods (60, 120 and 360 min). The periods were chosen based on Derby et al. (2016) who showed that krill meal can stimulate feeding for up to 3 h. Juvenile shrimp from a 1000 L holding tank (fed a commercially available diet from Ridley Corp. Australia) were sorted by weight and three shrimp allocated into each of 36 tanks (100L). ...
... Similar benefits of supplemental ingredients have been demonstrated by other authors. For example, supplementation with krill meal increased feed intake in L. vannamei by 28.9% (2.63 vs. 2.04 g) and 78.8% (7.42 vs. 4.15 g) after 1-h and 3-h periods respectively, compared to a control diet (Derby et al., 2016). Supplementation with squid meal produced similar responses of feed intake in L. vannamei over longer times whereby differences in feed preference between a control and squid-supplemented diet were more apparent at 120 min (P = 0.016) compared to 15 min (P = 0.106; Sanchez et al., 2005). ...
Aquaculture production can be improved by understanding how ingredients can affect feed intake and digestion. This is an area poorly understood for many aquaculture species, including for the shrimp Penaeus monodon. To investigate these processes, we measured feed intake, the rate at which digesta moves through the gastro-intestinal tract, the change of free amino acids (FAA) circulating in the haemolymph following feeding, and how different test ingredients affect these processes in this species. Diets supplemented with microbial NovacqTM (NQ), krill meal (KM) or whole squid meal (SQ) and a control diet were used across two separate experiments. In the first, feed intake was measured in communally housed shrimp for 60, 120 and 360 min to examine the effects of diet on ingestion. Feed intake after 360 min was greater in shrimp offered the SQ diet while no effect was observed at earlier time points. In the second experiment, individually housed shrimp were used to measure feed intake, the rate at which digesta passed through the gut and the change of individual FAA in the haemolymph over a 30 min period. For this experiment, addition of SQ and NQ increased both the rate at which digesta travels through the gut and post-prandial concentration of FAA in haemolymph at 5 min. Krill meal had the highest haemolymph concentration of amino acids at 10 min and all dietary treatments showed a convergence of haemolymph FAA by 30 min. The different ingredients appear to affect the appearance of FAA in haemolymph through different mechanisms. For SQ, the FAA content of the diet was high, being 2.8 times that of the others (27.6 vs. 10.0 g kg-1), and it is hypothesized that the availability of these FAA resulted in the rapid increase in haemolymph observed for this treatment. In contrast, two other ingredients also led to rapid increases in haemolymph FAA. However, for these diets the amount of FAA present was similar to the control indicating that other characteristics of the meals may be causal. Our data indicate that specific ingredients can increase both the rate at which digesta travels through the gut and the rate of absorption of amino acids and that these mechanisms could explain increases in both feed duration and intake
... Many aspects of the biology of this penaeid shrimp have been investigated (Pérez-Farfante, 1969;Dall et al., 1990;Alday-Sanz, 2010); and because it is one of the first decapod crustaceans to have a sequenced genome (Zhang et al., 2019), its potential for use as a model system is even greater. Additionally, knowing the behavior of individuals can aid in improving aquaculture production (Bardera et al., 2018), so the study of behavioral responses of individual shrimp to food and food-related cues can inform aquaculture practices (e.g., Derby et al., 2016;Bardera et al., 2019). For example, it is known that L. vannamei has a broad diet in nature (Pérez-Farfante, 1969;Dall et al., 1990;Ogle and Beaugez, 1991;Varadharajan and Pushparajan, 2013), and identification of chemoattractants in its food has guided the development of artificial diets (Nunes et al., 2006;Naylor et al., 2009;Suresh et al., 2011;Derby et al., 2016Derby et al., , 2018Morais and Derby, 2019). ...
... Additionally, knowing the behavior of individuals can aid in improving aquaculture production (Bardera et al., 2018), so the study of behavioral responses of individual shrimp to food and food-related cues can inform aquaculture practices (e.g., Derby et al., 2016;Bardera et al., 2019). For example, it is known that L. vannamei has a broad diet in nature (Pérez-Farfante, 1969;Dall et al., 1990;Ogle and Beaugez, 1991;Varadharajan and Pushparajan, 2013), and identification of chemoattractants in its food has guided the development of artificial diets (Nunes et al., 2006;Naylor et al., 2009;Suresh et al., 2011;Derby et al., 2016Derby et al., , 2018Morais and Derby, 2019). ...
... The effect of antennule ablation was also assayed for groups of animals. We did this because we wanted to determine whether the results for individual animals also applied to conditions used in aquaculture of shrimp as well as for animals in nature (Dall et al., 1990;Derby et al., 2016Derby et al., , 2018Morais and Derby, 2019). This assay was very similar to the attractability assay used for individual animals, except that it used groups of 10-15 animals in larger aquaria (74 cm long  30 cm wide  28 cm high, with 60 L of ASW), and only grabs (not movements) were quantified. ...
The Pacific white shrimp, Litopenaeus vannamei, is important as the principal species in the worldwide aquaculture of shrimp. It has also become a model in the study of crustacean biology, especially because it is one of the first decapod crustaceans to have its genome sequenced. This study examined an aspect of the sensory biology of this shrimp that is important in its aquaculture, by describing its peripheral chemical sensors and how they are used in acquiring and consuming food pellets. We used scanning electron microscopy to describe the diversity of sensilla on the shrimp's major chemosensory organs: antennules, antennae, mouthparts, and legs. Using behavioral studies on animals with selective sensory ablations, we then explored the roles that these chemosensory organs play in the shrimp's search for, and acquisition and ingestion of, food pellets. We found that the antennules mediate odor-activated searching for pellets, with both the lateral and medial antennular flagella contributing to this behavior and thus demonstrating that both aesthetasc (olfactory) and distributed chemosensors on the antennules can mediate this behavior. Once the shrimp finds and grasps the food pellet, the antennular chemoreceptors no longer play a role, and then the chemoreceptors on the mouthparts and legs control ingestion of the pellets. This sequence of chemosensory control of feeding in L. vannamei, a dendrobranchiate crustacean with small antennules and an ability to live and feed in both benthic and pelagic environments, is generally similar to that of the better-studied, large-antennuled, benthic reptantian crustaceans, including spiny lobsters (Achelata), clawed lobsters and crayfish (Astacidea), and crabs (Meirua).
... Palatability assessments were performed following the method from Derby et al. (2016). Thirty-two individuals of mud crabs with an average body weight of 178.78 ± 27.24 g were stocked individually in 35 L aquarium (44 × 30 × 30 cm) filled with 25 L seawater and aerated using air stones. ...
... The advantages of water stability in the feeds depend not only on the binding agent alone but also on the attractants that enhance the feed performance. The additions of feed stimulants help increase feed consumption by initiating a movement of the animal while locating the food (Lawrence et al., 2013;Derby et al., 2016). In the present studies, fresh meat from the mangrove clams brought strong chemical cues to the mud crabs. ...
The present study examined the physical characteristics of semi-moist formulated feeds to the reproductive maturation of female orange mud crab, Scylla olivacea. In this study, two experiments were conducted. The first experiment compared four types of natural diets; fish offal (discarded organ), mangrove clams (Polymesoda erosa), black devil snail (Faunus ater), and commercial shrimp feeds (control), to select the basal diet for the formulation of feeds. Proximate compositions of the different diets revealed that the mangrove clam, P. erosa (protein = 81.63% and lipid = 13.54%) is the most suitable ingredients for the mud crabs’ diet. Fatty acid analysis also showed that mangrove clams had the highest concentration of ARA, EPA, and DHA at 0.56%, 1.62%, and 2.68% respectively. In the second experiment, four isonitrogenous feed (~42%) with different lipid percentages; T1: 6%, T2: 8%, T3: 10%, and T4: 12% were formulated to investigate the effects of the lipid inclusion on maturation of mud crabs. The effects of different levels of lipid on palatability, feed water stability, nutrient leaching, buoyancy, and total solids were studied prior to feeding experimentation. The palatability tests showed high attractability of the crabs towards the feeds. Meanwhile, high water stability (dry matter retention) were recorded in all experimental feeds after long immersion hours, with low nutrient leaching, and low solids disintegration. Later, feeding trial on 120 matured female mud crabs (carapace width: 10.24 ± 0.66 cm and body weight: 186.42 ± 37.90 g) revealed that the semi-moist formulated feeds are readily accepted by the crabs. The crabs from all treatments recorded positive body weight gain (BWG) and specific growth rate (SGR) with crabs fed T4 dominating (BWG = 11.43 g, 14.65 g, and 12.13 g; SGR = 0.35%day⁻¹, 0.13%day⁻¹, and 0.08%day⁻¹ during 30-, 60-, and 90-day of feeding trials respectively) (p < 0.05). Similarly, morphological results showed that high GSI was noted in S. olivacea fed with T4, increasing at subsequent feeding trials (10.44%, 11.03%, and 14.51%) (p < 0.05), which were inversely proportional with the HSI (8.92%, 5.11%, and 4.76%) (p < 0.05) compared to other treatments, probably contributed by the high percentage of lipid inclusion. These findings demonstrate that diets contained 12% lipid and 42% protein (T4) is ideal for somatic and reproductive growth of S. olivacea. Yet, a nutrient dose-response study is expected to be carried out in the future to estimate the optimum lipid level required for reproductive and growth performance in S. olivacea.
... In addition, the concentrations of other essential amino acids, particularly isoleucine, leucine and phenylalanine,were higher in krill meal than fishmeal (Table 4). Consistently, growth performance stimulation with krill meal has been reported earlier in red swam crayfish (Gao et al., 2020), P. monodon , Atlantic salmon (Hatlen et al., 2017), P. vannamei (Nunes et al., 2011;Derby et al., 2016) and yellow croaker (Wei et al., 2019). Derby et al. (2016) reported that krill meal at 1, 3 and 6% inclusion increased the palatability and consumption of feed pellets in a concentration-dependent fashion in P. vannamei compared to the control group. ...
... Consistently, growth performance stimulation with krill meal has been reported earlier in red swam crayfish (Gao et al., 2020), P. monodon , Atlantic salmon (Hatlen et al., 2017), P. vannamei (Nunes et al., 2011;Derby et al., 2016) and yellow croaker (Wei et al., 2019). Derby et al. (2016) reported that krill meal at 1, 3 and 6% inclusion increased the palatability and consumption of feed pellets in a concentration-dependent fashion in P. vannamei compared to the control group. This enhanced palatability nature of krill meal is considered to be another reason for obtaining higher growth with higher inclusion in our study. ...
An eight-week feeding trial was conducted to investigate the effect of dietary krill meal inclusion in diets with moderate (12%) and low (6%) fishmeal concentrations for Penaeusvannamei.Inasmuch, eight iso‑nitrogenous and isolipidic diets were formulated to contain 36% crude protein and 5.5% crude lipid. In the moderate-fishmeal diets, krill meal was included at 0, 2, 4 and 6% (called FK12:0, FK12:2, FK12:4 and FK12:6, respectively), likewise in the low-fishmeal diets, krill meal was included at the same concentrations of 0–6% (called FK6:0, FK6:2, FK6:4 and FK6:6, respectively). Shrimp with a starting body weight of 0.55 ± 0.02 g were stocked at 22 animals per tank of 350 lcapacity and fed three times daily. Results revealed that dietary krill meal and fish meal inclusion levels significantly increased growth performance (P < 0.05)and there was no significant effect on interaction between fishmeal and krill meal levels. Shrimp fed 6% krill meal diet had the highest final body weight of 11.61 g, weight gain of 11.05 g, weight gain % of 1969.38%,specific growth rate of 5.41%/d and yield of 229.42 g/tank The weight gain % and SGR showed non significant difference between 4 and 6% krill meal containing groups.Dietary change did not affect feed conversion ratio, protein efficiency ratio and apparent protein utilization(P > 0.05). Survival was significantly increased in the groups containing 6 and 4% krill meal diets compared to 0% krill meal diet (P < 0.05). Inclusion levels of krill meal showed non-significant differences in post-fed body composition except for crude lipid and crude fibre content. Fishmeal inclusion levels showed significant (P < 0.05) variation in C14:0,C16:0,C18:0,C16:1, C18:1n-9,C18:2n-6,C22:6nn-3/n-6 ratio, whereas krill meal inclusion levels showed significant variation in the all n-3 fatty acids only. Immune-related gene expression was significantly (P < 0.05) upregulated in the shrimp fed high fishmeal diets (12%) for all the analyzed genes (ProPhenoloxidase (ProPO),ProPhenoloxidase activating enzyme (PPAE), Serine Protease (SP), β-1, 3-glucan-binding protein (BGBP), Superoxide dismutase (SOD), and Hemocyanin (HC)). The dietary change led to a significant difference in both histology and haematology parameters (P < 0.05). The results inferred that krill meal could be used as a potential functional feed ingredient in Penaeus vannamei.The present study suggested beneficial effects of krill meal in shrimp diets. The levels of fishmeal inclusion (12 and 6%) also showed significant (P < 0.05) variations in various growth performance parameters. It is plausible that an inclusion level of 4% is the minimum for a measurable difference in growth performance.
... Many methods have been applied to studying the role of shrimp behavior in developing diets and improving feeding management protocols (Bardera et al., 2019b). These methods usually include visual observations (Ahamad-Ali et al., 2007; de Lima et al., 2009;Derby et al., 2016;Nunes et al., 2006;Obaldo and Masuda, 2006;Pontes et al., 2008;Sanchez et al., 2005;Silva et al., 2019;Suresh et al., 2011) or video recordings (Bardera et al., 2019a;Bardera et al., 2021;Hunt et al., 1992;Nunes et al., 1997) in Y-mazes or translucent tanks with one or multiple chambers. Overall, these studies provided valuable information regarding mechanism of chemical detection and stimulation involved with feeding activity, as well as described several behavioral repertoires based on repeated movements of mouthparts and other appendages in penaeids (Bardera et al., 2019b). ...
... The addition of feeding effectors (chemoattractants, feeding incitants and stimulants) to improve feed detection and consumption has been usually evaluated in Y-mazes or compartmented tanks by observation of shrimp preferences and choice behavior (Derby et al., 2016;Nunes et al., 2006;Suresh et al., 2011). Recently, PAM was applied to evaluate the effects of feeding effectors (krill meal, krill oil and fish hydrolysate) added to a soybean-based practical diet on shrimp feeding behavior of L. vannamei (Soares et al., 2021). ...
Increasing availability of automated systems and technological solutions have been one of the most important trends in aquaculture nutrition for the past few decades as the industry focuses on improving feeding strategies through highly efficient automatic feeding technologies. Monitoring of aquatic animals is not a new practice but for the last few decades aquaculture has used feeding behavior monitoring as a tool to develop efficient demand feeders. While there are many devices available for the fish production sector, many rely on visual monitoring of individuals or populations, which disable its application in most shrimp production systems. However, production of sound by the mandibular occlusion has led to the study of passive acoustic monitoring of feeding behavior in shrimp and the development of passive acoustic demand feeding systems. While this technology has been available for less than a decade it has already been validated and adopted by the shrimp production industry. It is expected to continue being improved as more data is collected on both acoustic profiling and feeding algorithms. The objective of this publication is to present a detailed review of the information available so far about acoustic profiling of shrimp, the results of the application of this acoustic feeding system in production systems, discussing the limitations of this technology and what components could be improved in the future.
... However, studying shrimp feeding behavior is challenging in a number of ways and requires broad strategic approaches. Traditionally, most feeding behavioral studies with shrimps conducted under laboratory conditions include methods of direct visual observation (Sanchez et al., 2005;Nunes et al., 2006;Obaldo and Masuda, 2006;Pontes et al., 2006;Ahamad-Ali et al., 2007;Pontes et al., 2008;Lima et al., 2009;Suresh et al., 2011;Silva et al., 2012;Derby et al., 2016), video recordings with playback analysis Hunt et al., 1992;Nunes and Parsons, 1998) and video recordings with image software analysis (Bardera et al., 2019b) using glass aquaria or specially designed translucent tanks. Recently, the use of passive acoustics monitoring (PAM) has become an important tool to study the feeding behavior of penaeids, as their mandibles emit clicking sounds as they shred the feed during ingestion (Smith and Tabrett, 2013;Silva et al., 2019;Peixoto et al., 2020). ...
... Studies on feed consumption by shrimp usually focused on the total amount of feed eaten by a group of animals when the trials are terminated, not including behavioral observations such as changes in their ingestion behavior and rate of feed consumption during feeding trials (Derby et al., 2016). Meanwhile, shrimp behavioral repertoires in ethological studies are difficult to correlate to feed intake due to frequent misplacement or rejection of feed particles during the handling activity or passage through pre-oral mouthparts (Alexander and Hindley, 1985;Harpaz and Steiner, 1987;Steiner and Harpaz, 1987;Nunes and Parsons, 1998;Bardera et al., 2019a). ...
Studying shrimp feeding behavior is challenging and, traditionally, studies have been using direct visual observation or video recordings with image analysis under laboratory conditions. Passive acoustics monitoring (PAM) is a non-invasive approach to study feeding behavior of penaeids, as their mandibles emit clicking sounds during feed ingestion. Considering the wide variation available in shrimp diet lengths, our knowledge is still limited about their effects on feeding behavior. The present study was designed to use acoustics to evaluate the feeding behavior of Litopenaeus vannamei fed different diet lengths. A commercial pelleted diet with similar diameter (2.4 mm) and three different lengths was used as treatments “small” (2.35 mm), “medium” (4.26 mm) and “large” (8.42 mm). Three separate trials were performed with fastened shrimp (20 g), using omnidirectional hydrophones and external audio recorders. Our approach started with the characterization of the click acoustic parameters produced by three shrimps when fed the different diet lengths in anechoic chambers (15 L). We then analyze the number of clicks produced per pellet and duration of the clicking activity when shrimp fed a single pellet in individual tanks (1 L). Finally, the acoustic energy of feeding activity and feed consumption, as well as theirs relationship to predict feed intake was evaluated in aquaria (70 L) with five shrimps. The acoustic parameters of isolated clicks were not affected by the different diet lengths, however, doubling the length of the pellet resulted in doubling the number of clicks emitted during feeding activity. The duration of clicking activity per pellet indicated that small pellets are consumed 2.9 and 4.7 times faster than medium and large pellets, respectively. Furthermore, feeding acoustic energy of small pellets decreased rapidly after feed offer, as their faster consumption probably contributed to shrimps achieved satiety earlier than larger diets. Feed consumption was similar among diets length, but significantly correlated with the feeding acoustic energy emitted by L. vannamei, which is a breakthrough in feeding behavioral research. The results highlight the potential and possibilities of an acoustic approach to estimate feed consumption, as well as an alternative to traditional methods in feeding behavioral studies to improve efficiency of feed management.
... Practical shrimp feed formulations have traditionally relied on meals, solubles, and hydrolysates made from fish, squid, shrimp, krill, and mollusks to act as chemoattractants and feeding stimulants (Cruz-Ricque, Guillaume, Cuzon, & Aquacop, 1987;Cruz-Suárez, Guillaume & Wormhoudt, 1987;Guillaume, Cruz-Ricque, Cuzon, Wordmhoudt, & Revol, 1989;Lee & Meyers, 1997;Smith, Tabrett, Barclay, & Irvin, 2005;Grey, Forster, & Dominy, 2009;Nunes et al., 2006;Suresh et al. 2011;Derby et al., 2016). These raw materials contain natural chemical drivers, which activate shrimp feeding behavior by promoting feed detection, and search and orientation toward the food source (known as chemoattractants). ...
... These raw materials contain natural chemical drivers, which activate shrimp feeding behavior by promoting feed detection, and search and orientation toward the food source (known as chemoattractants). Some can also stimulate feeding activity through initiation and continuation of feeding (Costero & Meyers, 1993;Derby et al., 2016;Lee & Meyers, 1996Nunes et al., 2006). These positive behavioral feeding responses appear to ultimately lead to a growth-enhancement effect in penaeid shrimp (Cruz-Ricque et al., 1987;Cruz-Suárez et al., 1987;Guillaume et al., 1989;Córdova-Murueta & García-Carrenõ, 2002;Smith et al., 2005;Williams, Smith, Barclay, Tabrett, & Riding, 2005;Suresh et al. 2011). ...
This study compared the feed preference and growth response of Litopenaeus vannamei to chemoattractants. A diet with 3% fishmeal was supplemented with either 3% salmon meal (POS), 3% soy protein concentrate (NEG), 3% krill meal (KRM), 3% squid meal (SQM), 3% shrimp head meal (SHM), 3% shrimp meal (SM), 3% squid liver meal (SLM), or 5% liquid sardine hydrolysate (SAH). Shrimp with a body weight (BW) of 0.99 ± 0.08 g were stocked at 100 animals/m2 in 56 tanks of 1 m3 and fed 10 times daily for 74 days. Feed preference was evaluated by feeding shrimp of 10.87 ± 1.82 g in excess twice a day for 10 days in two separate feeding trays allocated in 50 tanks of 0.5 m3. Survival reached 93.3 ± 5.80% and was unaffected by supplementation. Final BW was the highest for shrimp fed the KRM‐supplemented diet (11.97 ± 0.93 g), followed by POS (11.11 ± 0.77 g) and SQM (11.01 ± 1.17 g). Diets SHM, SM, SLM, and NEG showed a lower shrimp BW than POS, but were not statistically different among them. Shrimp fed the SAH diet achieved the lowest BW (10.06 ± 1.02 g). The highest gained yield was obtained with diets KRM and POS. No statistical difference was observed in shrimp yield among other diets. The lowest feed conversion ratio (FCR) was achieved with shrimp fed KRM (1.31 ± 0.05) when compared to diets SHM (1.47 ± 0.05), SAH (1.47 ± 0.07), and SLM (1.45 ± 0.17). Two‐by‐two comparisons indicated that shrimp preferred SHM and KRM, except when these were compared to SQM and SLM. No difference in feed preference was found between diets with SQM and SLM. SAH was the least preferred raw material in all comparisons. Results indicated that KRM acts as a powerful feeding effector and growth enhancer in fishmeal‐challenged diets for whiteleg shrimp. A dietary supplementation with 3% KRM is more effective than the same dose of any other chemoattractant evaluated.
... In the case of shrimps, the inclusion of fish protein hydrolysates, which contain a higher concentration of low molecular weight peptides compared to an unhydrolysed protein source [19], was introduced. These hydrolysates stimulate arousal, trigger search initiation, and aid in food location in shrimp species [20]. This strategy is rooted in a deep understanding of shrimp ethology [18], leveraging their natural evolutionary drivers to optimise feed consumption. ...
To achieve production goals, aquaculture often modifies the environments of farmed species, creating conditions that differ significantly from their natural habitats. These alterations can result in evolutionary mismatches, where traits that evolved to optimise survival and reproduction in the wild become maladaptive in farming settings. This can lead to a conflict between traits desired for farming and those favoured by natural selection. In this opinion piece, we examine cases where such evolutionary mismatches arise, their impact on production, and strategies to mitigate these effects. We provide examples of species and farming practices that have been optimised through selective breeding and evolutionary studies and highlight practical solutions that can be applied to the many aquaculture species for which farming practices remain suboptimal. Additionally, we suggest directions for future research to deepen our understanding of evolutionary mismatches in aquaculture.
... From an aquaculture perspective, krill products are further valuable due to their content of bioactive constituents, including cholesterol, minerals, and vitamins [6], as well as water-soluble, low-molecular-weight feed attractants encompassing free amino acids, nucleotides, nucleosides, quaternary ammonium compounds, phospholipids (PLs), biogenic amines, and chitin. These compounds collectively enhance the attractability and palatability of diets [17,18]. ...
Marine sources of omega-3, proteins, and other nutrients are in increasing demand, while supply is struggling to meet this demand increase. A key focus for meeting the need for marine ingredients for human and animal nutrition is ensuring sustainable sourcing for both the oceans as well as other production types. Aker BioMarine is harvesting and producing marine ingredients from krill and this communication is intended to showcase how the harvesting and production of such ingredients are performed in a sustainable way. This communication is written to describe the krill fisheries’ management, to provide demonstration cases from CO2 hot spotting, and show how results from these are used to target GHG emission reduction. The initiatives that are taken to ensure sustainable fishing and production, as well as examples of short- and long-term actions to reduce and minimize the impact of all activities, are provided.
... Traditionally, research on agonistic behavior in shrimp has primarily been conducted under laboratory conditions using methods such as direct visual observation, video recordings with subsequent playback analysis, and video recordings paired with image software analysis in glass aquaria or specially designed translucent tanks [15][16][17][18]. Concurrently, researchers have applied statistical analysis and mathematical modeling to construct animal behavioral models [17,19]. ...
Agonistic behavior has been identified as a limiting factor in the development of intensive L. vannamei aquaculture. However, the characteristics and molecular mechanisms underlying agonistic behavior in L. vannamei remain unclear. In this study, we quantified agonistic behavior through a behavioral observation system and generated a comprehensive database of eyestalk and brain ganglion tissues obtained from both aggressive and nonaggressive L. vannamei employing transcriptome analysis. The results showed that there were nine behavior patterns in L. vannamei which were correlated, and the fighting followed a specific process. Transcriptome analysis revealed 5083 differentially expressed genes (DEGs) in eyestalk and 1239 DEGs in brain ganglion between aggressive and nonaggressive L. vannamei. Moreover, these DEGs were primarily enriched in the pathways related to the energy metabolism process and signal transduction. Specifically, the phototransduction (dme04745) signaling pathway emerges as a potential key pathway for the adjustment of the L. vannamei agonistic behavior. The G protein-coupled receptor kinase 1-like (LOC113809193) was screened out as a significant candidate gene within the phototransduction pathway. Therefore, these findings contribute to an enhanced comprehension of crustacean agonistic behavior and provide a theoretical basis for the selection and breeding of L. vannamei varieties suitable for high-density aquaculture environments.
... Antarctic krill (Euphausia superba) is a zooplankton species already in use for shrimp diets. Krill meal inclusion in diets for whiteleg shrimp has been shown to increase feed intake [13,14] and improve overall nutritional quality [15][16][17]. ...
Shrimp feed formulations have moved towards less fish meal and more of the readily available and cheaper plant proteins. To counteract the lower attractiveness and palatability of plant proteins, feeds are supplemented with ingredients known to have chemoattractive properties that will increase feed intake. This study investigated the putative chemoattractive effect of Calanus finmarchicus hydrolysate, when used as a dietary supplement in shrimp feeds. C. finmarchicus is a zooplankton species native to the northern Atlantic Ocean and is a novel and sustainable raw material for shrimp feed products. Diet attractiveness was evaluated in a 24-day feeding trial with whiteleg shrimp (Litopenaeus vannamei) by measuring the intake of 12 diets with various levels of fish meal, calanus hydrolysate, and krill (Euphausia superba) meal. Higher inclusion rates of both ingredients resulted in increased feed intakes, and supplementing the high fish meal diet with calanus hydrolysate gave a statistically significant higher feed intake. Low molecular weight peptides, chemoattractive amino acids, and the water-soluble nature of the hydrolysate could explain the chemoattractive properties observed in the study.
... Therefore, it has been widely used in commercial hatcheries of Chinese mitten crab in China [10]. Previous studies have illustrated that Antarctic krill meal supplementation could enhance growth performance and promote feed utilization in crustaceans [27,28]. In contrast, Nunes et al. [29] and Guo et al. [18] demonstrated that dietary low Antarctic krill meal supplementation had no positive influence on the growth performance of L. vannamei and P. trituberculatus, respectively. ...
A 60-day feeding trial was conducted to evaluate the impact of dietary Antarctic krill meal on the reproductive performance and embryo quality of the Chinese mitten crab, Eriocheir sinensis. Three diets were formulated, incorporating varying levels of Antarctic krill meal at 0% (Diet K0), 10% (Diet K10), and 20% (Diet K20), with a control group fed razor clam Sinonovacula constricta. Each diet was randomly assigned to three replicate tanks, each stocked with 5 males and 10 females. Male and female weights were 145.38 ± 8.01 and 102.57 ± 9.73 g, respectively. The results revealed no significant differences in weight gain rate, specific growth rate, and survival rate. However, the hepatopancreatic weight and hepatopancreas index of female crabs in each group decreased, while gonadal weight and gonadosomatic index increased significantly after 60 days, with Diet K20 showing the highest values. Egg production and fecundity of female crabs reached their peak in Diet K20, with no significant differences in reproductive indices among all groups. The phospholipid content in Diet K20 was significantly higher than in the other groups (P<0.05). Cholesterol contents in Diet K0 and the control group were significantly higher than in Diet K10 and K20 (P<0.05). No significant differences were observed in egg diameter, egg weight, moisture, crude protein, and crude fat between the groups. The content of C20 : 2 and C20 : 4n6 was highest in Diet K0, with a significant difference compared to Diet K10 (P<0.05). However, no significant differences were found in the total content of saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids among all groups. Based on the research findings, it is recommended that the optimal level of Antarctic krill meal in diets is 20%.
... Furthermore, passive acoustics do not require any attachments equipped on the detected objects. To monitor the feeding activities of aquatic animals, most of the research relied on direct observation [33] or video recording [34]. These methods, especially direct observation, are difficult for further analyses of the acoustic characteristics. ...
In order to analyze the sound production mechanism and the acoustic characteristics of Haliotis discus hannai during feeding, this paper proposes a multi-source information fusion approach combining passive acoustics with videos. In the experiments, abalones with a shell length of 60 ± 2.7 mm were divided into two groups: Group A was fed with fresh macro algae Gracilaria lemaneiformis as food once each day; Group B was placed on a small amount of sand as impurities at the bottom of the tank. As control groups, Group C did not have abalone or food and Group D did not have abalones but food was added. The eating acoustic signals of abalone were mainly concentrated in the frequency range between 9.49 kHz and 44.36 kHz, wherein the peak frequency is 37.86 ± 2.55 kHz, with the maximum energy -66.43 ± 5.17 dBm/Hz. Each pulse sequence is with a duration of 119.12 ± 70.51 ms and consists of several sub-pulses. Nearly 70% of the pulse sequences consist of 1~2 sub-pulses and the duration of the pulse containing one sub-pulse is 42.62 ± 19.72 ms. The eating rate was kept at 0.61 ± 0.04 times/min at the beginning and was decreased significantly to 0.48 ± 0.08 times/min after 60 mins. Note that the characteristic analysis of abalone acoustic signals during feeding are first reported in this manuscript to the best of our knowledge, and this paper also demonstrates that the sound of abalone is produced by scraping and grinding food with radula. Because the eating rate decreases with the reduction in the abalone’s level of hunger, the results may be used as an acoustic indicator of feeding strategy for the abalone aquaculture industry.
... Dry and sinking pellets are used for shrimp feeding [51]. Derby et al. [52] observed that the first pellets were consumed quickly by shrimp after feeding. Then, they slowly consumed pellets with greater manipulation using their legs and mouthparts. ...
This study was conducted to determine the dietary riboflavin requirement and its effects on growth performance, feed utilization, innate immunity, and diet digestibility of Litopenaeus vannamei. A riboflavin-free basal diet (R0) was formulated as a control, and six other diets were prepared by adding riboflavin of 10, 20, 30, 40, 50, and 60 mg/kg to the basal diet (designated as R10, R20, R30, R40, R50, and R60, respectively). Quadruplicate groups of shrimp (initial average weight 0:17 ± 0:00 g) were fed the diets six times a day for 8 weeks. Weight gain, specific growth rate, and protein efficiency ratio were significantly increased by riboflavin (p < 0:05). The maximum values were observed in shrimp fed R40 diet. The highest activities of phenoloxidase, nitro blue tetrazolium, superoxide dismutase, and glutathione peroxidase were observed in shrimp fed R40 diet. Lysozyme activity was significantly higher in shrimp fed R30 and R40 diets than that of shrimp fed R60 diet (p < 0:05). Intestinal villi were significantly longer in shrimp fed R50 and R60 diets compared to those of all other groups while the shortest villi were observed in R0 group (p < 0:05). Intestinal villi were clearly distinguished in shrimp fed higher levels of riboflavin compared to those of shrimp fed R0 and R10 diets. Apparent digestibility coefficients of dry matter and protein in diets were not significantly affected by riboflavin levels (p < 0:05). Whole-body proximate composition and hemolymph biochemical parameters were not significantly altered by dietary riboflavin (p < 0:05). Therefore, the results of this study indicate that riboflavin is essential to enhance growth performance, feed utilization, nonspecific immunity, and intestine morphology of shrimp. An optimal riboflavin requirement for the maximum growth of L. vannamei seems to be approximately 40.9 mg/kg diet.
... Difference of superscript letters in the same row indicate statistical significance (P < 0:05). 7 Aquaculture Nutrition [33,36,37]. As was observed in the present study, crabs fed with the KM10 diet had higher PWG and SGR than those fed with the KM30 diet. ...
An 8-week feeding trial was carried out to assess the effect of dietary krill meal on growth performance and expression of genes related to TOR pathway and antioxidation of swimming crab (Portunus trituberculatus). Four experimental diets (45% crude protein and 9% crude lipid) were formulated to obtain different replacements of fish meal (FM) with krill meal (KM); FM was replaced with KM at 0% (KM0), 10% (KM10), 20% (KM20), and 30% (KM30); fluorine concentration in diets were analyzed to be 27.16, 94.06, 153.81, and 265.30 mg kg-1, respectively. Each diet was randomly divided into 3 replicates; ten swimming crabs were stocked in each replicate (initial weight, 5.62±0.19 g). The results indicated that crabs fed with the KM10 diet had the highest final weight, percent weight gain (PWG), and specific growth rate (SGR) among all treatments (P
... Since plant protein sources are taurine-deficient, taurine is also frequently added to plant-based diets due to its role in lipid digestion, bile acid conjugation and antioxidant defence (Salze and Davis, 2015), and as an attractant and feed stimulant . Also, diet palatability may be enhanced through the inclusion of krill meal, as showed in Pacific white shrimp, Litopenaeus vannamei (Derby et al., 2016) and blue shrimp, Litopenaeus stylirostris (Suresh et al., 2011). This ingredient has the advantage of also being an excellent source of marine phospholipids (Saleh et al., 2013a;. ...
The sustainability of the aquaculture industry depends on formulating diets that promote nitrogen retention and maximise fish growth performance. This Thesis was focused on the optimisation of environmentally sustainable and cost-effective feeds for two fish species relevant to the World and European aquaculture: Nile tilapia (Oreochromis niloticus) and gilthead seabream (Sparus aurata). Chapter II aimed to reduce protein inclusion levels in plant-based diets for juvenile tilapia, through adequate amino acid supplementation, to minimise diet environmental impact and increase biological efficiency. Results showed that dietary protein content may be reduced to 30% without hindering growth performance. Additionally, amino acid supplementation of a lower protein diet improved protein utilisation and decreased amino acid catabolism, leading to lower nitrogen losses. In Chapter III, the bioavailability and metabolic fate of ketogenic and glucogenic amino acids in juvenile seabream fed plant-based diets with distinct protein and/or lipid content was evaluated. Results established that the metabolic fate of amino acids was mainly affected by their nature rather than the diet formulations. Similar results were obtained in Chapter IV in seabream fed diets differing in the inclusion of lipids with distinct protein to energy ratios. Findings from Chapters III and IV showed that in seabream juveniles methionine was preferentially retained in the muscle while lysine was catabolised. In Chapter V, the influence of different methionine sources on metabolism and growth of tilapia was investigated. Fish fed a diet supplemented with DL-methionine showed improved growth compared with fish fed a non-supplemented diet, while dietary supplementation with methyl hydroxyl analogue resulted in intermediate values. The impact on fish growth was probably due to the distinct metabolic pathways used for converting methionine, which were different between sources. Chapter VI evaluated growth performance, diet digestibility and nitrogen balance in seabream reared under low temperatures. The supplementation of feed additives in diets for seabream juveniles enabled the decrease of protein and fishmeal contents by increasing diet digestibility and lowering nitrogen faecal losses. This Thesis generated relevant knowledge on nutritional strategies to promote nitrogen retention and maximise fish growth, towards a more sustainable aquaculture.
... Lemos et al. (2009) Lemos et al., 2009) and at 95.1% for P. monodon (644 g kg −1 CP, 211 g kg −1 lipid, and 118 g kg −1 ash; Glencross et al., 2018). A number of other studies have reported a positive effect on the feeding and growth of juvenile L. vannamei when fed low dietary inclusions of KRM (Nunes et al., 2011(Nunes et al., , 2019Suresh et al., 2011;Sá et al., 2013;Derby et al., 2016). ...
This study determined the apparent digestibility for crude protein (ACPD) and essential aminoacids (AEAAD) of ingredients for Litopenaeus vannamei fed diets containing soy protein concentrate (SPC), corn gluten meal (CGM), poultry byproduct meal (PBM), meat and bone meal (MBM), hydrolyzed feather meal (HFM), spray-dried blood meal (DBM), tilapia byproduct meal (TBM), Brazilian marine fish meal (BFM), salmon byproduct meal (SLM), and krill meal (KRM). Digestibility was estimated using chromic oxide as a marker in a reference (REF) mixture. Shrimp of 6-8 g body weight were reared over three separate experimental stages lasting 29-30 days each. Shrimp survival exceeded 96% and was unaffected by test ingredient. The ACPD ranged from 66.7% for a diet containing DBM to 84.2% for the REF diet. Higher ACPD were observed for aquatic compared with plant and terrestrial animal byproducts. Aside from SPC (79.3%), ACPD for CGM was low at 47.5%. Among terrestrial animal byproducts, ACPD was higher for MBM compared with PBM, DBM, and HFM (71.2, 62.8, 48.6, and 45.9%, respectively). With the exception of BFM (59.7%), ACPD for all other aquatic proteins was high (KRM, 84.3%; TBM, 83.3%; SLM, 78.9%). Aquatic proteins have higher crude protein (CP) and essential aminoacid (EAA) digestibility for shrimp. Ingredients SLM, SPC, TBM, and KRM are preferable in feeds for the whiteleg shrimp since they carry a high CP and EAA content (>600 g kg⁻¹) combined with ADC near or in excess of 80%.
Keywords:
available aminoacids; digestibility; digestible protein; whiteleg shrimp
... The actual biological mechanisms by which these 'growth factors' promote culture performance remain poorly characterized. For krill meal, a growth factor was isolated from its insoluble protein fraction [177], and krill meal was demonstrated to have a positive effect on feed palatability through increasing the feeding duration [182]. For marine microbial biomass, a range of potential bioactive nutrients has been measured [135]. ...
Intensification of the shrimp sector, also referred to as vertical expansion, has been predominately driven by consecutive incidences of global disease outbreaks, which have caused enormous economic loss for the main producer countries. A growing segment of the shrimp farming industry has opted to use production systems with higher density, biosecurity, and operating control to mitigate the risks posed by disease. However, successful super-intensive shrimp production is reliant on an advanced understanding of many important biological and economic parameters in the farming system, coupled with effective monitoring, to maintain optimal production. Compared to traditional extensive or semi-intensive systems, super-intensive systems require higher inputs of feed, energy, labor, and supplements. These systems are highly sensitive to the interactions between these different inputs and require that the biological and economical parameters of farming are carefully balanced to ensure success. Advancing nutritional knowledge and tools to support consistent and efficient production of shrimp in these high-cost super-intensive systems is also necessary. Breeding programs developing breeding-lines selected for these challenging super-intensive environments are critical. Understanding synergies between the key areas of production systems, nutrition, and breeding are crucial for super-intensive farming as all three areas coalesce to influence the health of shrimp and commercial farming success. This article reviews current strategies and innovations being used for Litopenaeus vannamei in production systems, nutrition, and breeding, and discusses the synergies across these areas that can support the production of healthy and high-quality shrimp in super-intensive systems. Finally, we briefly discuss some key issues of social license pertinent to the super-intensive shrimp farming industry.
... A similar result was reported by Schmitt and Santos (1998) in P. paulensis, wherein a higher nitrogen intake in shrimp fed with squid than that of formulated diets was observed which might be related to numerous factors, mainly its attractive characteristics with balanced amino acid profiles of squid. Similarly, the better performances of various fresh protein sources have earlier been reported in Atlantic salmon (Julshamn et al., 2004), Atlantic halibut (Suontama et al., 2007), P. monodon Williams et al., 2005), P. stylirostris (Suresh & Nates, 2011) and P. vannamei (Derby et al., 2016;Nunes et al., 2011). ...
An indoor experiment was carried out to assess the effect of various fresh foods and formulated diets on oxygen consumption in relation to nitrogen metabolism in Penaeus monodon. Seven iso-nitrogenous diets were formulated by substituting fishmeal (w/w) at 0 (control), 2.5 and 5% using groundnut oil cake (GNC-1 and GNC-2, respectively), rapeseed meal (RSM-1and RSM-2) and sesame oil cake (SOC-1 and SOC-2). Simultaneously, five different fresh foods (clam, crustaceans, fish, polychaete and squid) were also tested. Results revealed that nitrogen intake increased (p < 0.05) by 10.5%–86.6% in shrimp fed fresh food compared with control. Among the fresh food, fish meat showed the highest (p < 0.05) oxygen consumption and ammonia-N efflux. The O:N ratio decreased by 4.22–6.62 in shrimp fed on fresh food, whereas it increased by 0.91–3.28 in formulated diets. Regression analysis revealed a higher coefficient of determination for oxygen consumption (R2 = 0.9272) as well as ammonia-N excretion (R2 = 0.8778) in fresh food compared with the formulated feeds (0.3818 and 0.2187), whereas it was found to be low for O:N ratio for both the fresh food (R2 = 0.1789) and formulated feeds (R2 = 0.3260). The results confirmed that the measurement of O:N ratio can be an additional tool for assessing the nutritional quality of feed along with growth and digestibility and was more significant with the nutritional quality of formulated diets in P. monodon over fresh foods, in relation to nitrogen metabolism.
... Some experiments have used krill meal as a supplement to improve the quality of feed containing soybean meal. Krill meal is a chemostimulant whose major effect when added to feed pellets is to increase the pellets' palatability by prolonging the feeding session and thus the amount eaten, but not affecting how quickly a shrimp eats each pellet (Derby et al. 2016b). Using this experimental method, a highly effective chemostimulant without animal products was developed. ...
Aquatic organisms detect chemical cues to sense the local environment, for example, to find a mate, locate food, and identify danger. Knowledge of chemical cues can be used in aquaculture, in practical applications such as controlling mating behavior to increase fertility, enhance feeding, and decrease stress; in fisheries, by catching selected species with low-cost artificial attractants; and to address maritime issues, by decreasing biofouling. Aquatic organisms also detect chemical cues related to global environmental changes, ocean acidification, and increases in ocean plastics, all of which can affect their chemosensory behaviors. Here we discuss the nature of chemical cues and chemosensory biology and ecology of aquatic organisms, and potential applications with an emphasis on sex pheromones in commercially important and well-studied animals, namely, decapod crustaceans and fish.
... Previous studies have reported on the utilization of marineand terrestrial animal-based ingredients as an effective CA or/and FS in decapod crustaceans farming (e.g. Smith et al., 2005;Ali et al., 2007;Derby et al., 2016;Nunes et al., 2006Nunes et al., , 2019. However, these ingredients can be varied in their chemical compositions when they are obtained from different production sources or suppliers, mostly due to the different processing methods that have been used. ...
The aquaculture of decapod crustaceans is expanding continuously to supply protein source for human consumption. Therefore, intensive research is necessary to improve the quality of the feeds in decapod crustacean farming. Decapod crustaceans are slow feeders, and dietary inclusion of plant proteins reduces their intakes on the feeds. Dietary supplementation of chemoattractants (CA) (to reduce food searching duration) and feeding stimulants (FS) (to stimulate ingestion) is therefore necessary to solve these problems respectively. Amino acids are commonly used as the CA and FS in aquaculture, and the feeding response of aquatic animals to amino acids is species-specific. As the chemosensory systems of decapod crustaceans are complicated, and their feeding responses are different from fish, it is essential to understand which amino acids can function as the CA, FS or both to the targeted farmed species. This review provides an overview on the acceptance of some commercially farmed decapod crustaceans to amino acids. Topics related to the efficiency of amino acids being a CA and FS were discussed, and recommendations on how to present amino acids as a CA and FS efficiently in decapod crustacean farming were also made.
... Modern technology offers the possibility for real-time shrimp behavior monitoring in aquaculture as a fast and automatic research topic and a repeatable method [19]. In general, when shrimps are in different physiological states, their behavioral profile will change, such as posture, sound frequency, and activity rhythms [20][21][22]. Figure 1 shows the number of papers related to different methods and monitoring behaviors. The most popular methods are acoustic technology, machine vision, and movement sensors. ...
Crustacean farming is a fast-growing sector and has contributed to improving incomes. Many studies have focused on how to improve crustacean production. Information about crustacean behavior is important in this respect. Manual methods of detecting crustacean behavior are usually infectible, time-consuming, and imprecise. Therefore, automatic growth situation monitoring according to changes in behavior has gained more attention, including acoustic technology, machine vision, and sensors. This article reviews the development of these automatic behavior monitoring methods over the past three decades and summarizes their domains of application, as well as their advantages and disadvantages. Furthermore, the challenges of individual sensitivity and aquaculture environment for future research on the behavior of crustaceans are also highlighted. Studies show that feeding behavior, movement rhythms, and reproduction behavior are the three most important behaviors of crustaceans, and the applications of information technology such as advanced machine vision technology have great significance to accelerate the development of new means and techniques for more effective automatic monitoring. However, the accuracy and intelligence still need to be improved to meet intensive aquaculture requirements. Our purpose is to provide researchers and practitioners with a better understanding of the state of the art of automatic monitoring of crustacean behaviors, pursuant of supporting the implementation of smart crustacean farming applications.
... Since plant protein sources are taurine-deficient, taurine is also frequently added to plant-based diets due to its role in lipid digestion, bile acid conjugation and antioxidant defence (Salze and Davis, 2015), and as an attractant and feed stimulant (Chatzifotis et al., 2009). Also, diet palatability may be enhanced through the inclusion of krill meal, as showed in Pacific white shrimp, Litopenaeus vannamei (Derby et al., 2016) and blue shrimp, Litopenaeus stylirostris (Suresh et al., 2011). This ingredient has the advantage of also being an excellent source of marine phospholipids (Saleh et al., 2013a(Saleh et al., , 2018. ...
Gilthead seabream (Sparus aurata) is vulnerable to low water temperature, which may occur in the Southern Europe and Mediterranean region during Winter. Fish are poikilothermic animals, therefore feed intake, digestion, metabolism and ultimately growth are affected by water temperature. This study aimed to evaluate growth performance, feed utilisation, nutrient apparent digestibility, and nitrogen losses to the environment in gilthead seabream juveniles reared under low temperature (~ 13 °C). Three isolipid and isoenergetic diets were formulated: a diet similar to a commercial feed (COM) that contained 44% crude protein and 27.5% fishmeal, and two experimental diets with a lower protein content of 42% (ECO and ECOSup). In both ECO diets fishmeal inclusion was reduced (10% in ECO and 7.5% in ECOSup diet) and 15% poultry meal was included. Additionally, the ECOSup diet was supplemented with a mix of feed additives intended to promote fish growth performance and feed intake. The ECO diets presented lower production costs than the COM diet, whilst incorporating more sustainable ingredients. Gilthead seabream juveniles (±154.5 g initial body weight) were randomly assigned to triplicate tanks and fed the diets for 84 days. Fish fed the ECOSup diet attained a similar final body weight than fish fed the COM diet, significantly higher than fish fed the ECO diet. ECOSup fed fish presented significantly higher hepatosomatic index than COM fed fish, most likely due to higher hepatic glycogen reserves. The viscerosomatic index of ECOSup fed fish were significantly lower compared to COM fed fish, which is a positive achievement from a consumer's point of view. ECOSup diet exhibited similar nutrient digestibility than the COM diet. Moreover, feeding fish with the ECO diets resulted in lower faecal nitrogen losses when compared to COM fed fish. The results suggest that feeding gilthead seabream with an eco-friendly diet with a mix of feed additives such as the ECOSup diet, promoted growth and minimised nitrogen losses to the environment. Nutritional strategies that ultimately promote feed intake and diet utilisation are valuable tools that may help conditioning fish to sustain growth even under low temperatures.
... Shrimp benthic habits and anatomical characteristics of mouthparts are major setbacks to visualize and quantify their feeding behavior using traditional methods of direct visual observation or video recordings analysis under laboratory conditions (Hunt et al. 1992;Sanchez et al. 2005;Nunes et al. 2006;Obaldo and Masuda 2006;Pontes et al. 2008;Lima et al. 2009;Suresh et al. 2011;Silva et al. 2012;Derby et al. 2016;Bardera et al. 2019b). These difficulties are increased under field conditions due to water depths and low visibility in production ponds. ...
This study aimed to compare the growth performance, food consumption, and acoustic feeding behavior of two size classes of Litopenaeus vannamei fed on extruded and pelleted diets. Two similar diets (35% crude protein) prepared by extrusion or pelletizing methods were offered to two shrimp size classes: small (3.83 ± 0.16 g) and large (10.28 ± 0.37 g). Shrimp were reared in 100-L aquaria (salinity 6 ppt, temperature 28 °C); growth performance and survival were analyzed at the end of 4 and 8 weeks for small and large size classes, respectively. Hydrophones recorded the sounds of shrimp feeding activity for 30-min intervals, after food remains were collected to evaluate consumption. Physical (pellet durability index, hardness, water absorption, density, sinking velocity, dry matter retention) and chemical (aromatic amino acids (AAA) leaching) characteristics of the diets were evaluated before and after soaking. Extruded diet presented higher durability and hardness before soaking, but its higher water absorption resulted in markedly texture softened and higher AAA leaching. Both shrimp size classes presented no significant differences in final mean weight, biomass, weight gain, survival, food conversion, and food consumption between pelleted or extruded diets. The mean acoustic energy did not differ between diets, but larger shrimp produced higher energy during feeding activity. The energy showed a significant progressive decrease along time intervals (10, 20, and 30 min) for both size classes and diets. Despite the different characteristics between pelleted and extruded diets, both resulted in similar shrimp performance and acoustic feeding profile activity under laboratory conditions.
... Grey et al., (2009) reported that different salmon hydrolysates tested were effective feeding attractants when included in soybean meal-based diets for L. vannamei. Derby et al., (2016) observed an increase in the feed consumption of L. vannamei by increasing the inclusion levels of krill meal from 1% to 6%. Similar results were found by adding 1% to 5% of krill meal in Penaeus monodon diets, but the opposite was observed for squid meal (Smith et al., 2005). ...
Current study was conducted to evaluate the efficacy of modified canola oil (MCO) with enhanced levels of omega 3 fatty acids, to replace menhaden fish oil (MFO) in practical diets (36% protein and 8% lipid) of Litopenaeus vannamei. In first two trials, the basal diet containing 100% MFO was incrementally replaced by 25%, 50%, 75% and 100% MCO, which clearly demonstrated the potential of using MCO as a replacement for up to 75% of the supplemented MFO in poultry meal‐based diets. In the third trial, two series of diets were evaluated including fishmeal‐based diets replacing MFO by 25%, 50%, 75% and 100% MCO and three poultry meal‐based diets with 100% MFO, 75% MCO and 75% MCO supplemented with 4% hydrolysed salmon by‐product meal (HSM) as an attractant. In conclusion, no significant differences in performances of shrimp between diets were noted indicating no palatability issue in poultry meal‐based MCO diet and confirmed the efficacy of replacing 100% MFO by MCO in a low fishmeal diets and up to 75% in poultrymeal‐based diets without compromising the growth of shrimp.
... As a first step, we developed standardized assays of attractability and palatability to study chemosensory behavior in the laboratory ( Derby et al., 2016 ...
... As a first step, we developed standardized assays of attractability and palatability to study chemosensory behavior in the laboratory ( Derby et al., 2016 ...
... For many years, the main source of vegetable protein for shrimp feed was obtained from terrestrial plant, such as soybean meal (Cruz-Suarez et al., 2009;Suárez et al., 2009;Derby et al., 2016;Sharawy et al., 2016;Xie et al., 2016), lupin meal (Draganovic et al., 2014), garden pea Pisum sativum, concentrated rice protein (Oujifard et al., 2012;Chen et al., 2017), and canola meal Brassica sp. (Kou et al., 2015;Suárez et al., 2009;Singh et al., 2014). ...
The study aimed to evaluate the utilization of seaweed Caulerpa racemosa as feed ingredient for tiger shrimp Penaeus monodon. This research consisted of two different stages, i.e. digestibility and growth test. Tiger shrimp with average body weight of 5.70 ± 0.42 g was reared during digestibility test. The measured parameters were total protein, calsium, magnesium, and energy digestibility. The growth test was managed by using a completely randomized design consisted of four different treatments (in triplicates) of dietary C. racemosa meal addition levels, i.e. 0 (control), 10, 20, and 30%. Tiger shrimp with an average body weight of 0.36 ± 0.02 g were cultured for 42 days in plastic containers (70×45×40 cm) with a stocking density of 15 shrimp/container. Apparent dry matter, protein, calcium, magnesium, and energy digestibilities of C. racemosa were 51.82, 88.67, 68.44, 16.39, 60.30%, respectively. The results presented that the growth performance of tiger shrimp fed with diet containing 10% of C. racemosa was not significantly different with the control (P>0.05). However, the growth performance of the shrimp fed with diet containing more than 20% of C. racemosa decreased. The enzyme activitity of superoxide dismutase (SOD) increased with the higher level of dietary addition of C. racemosa. It can be concluded that C. racemosa was possibly applied up to 10% in the feed formulation for tiger shrimp.
Keywords: Caulerpa racemosa, Penaeus monodon, digestibility, growth performance, shrimp
ABSTRAK
Penelitian ini bertujuan mengevaluasi pemanfaatan rumput laut Caulerpa racemosa sebagai bahan baku pakan udang windu Penaeus monodon. Penelitian ini dilakukan dengan dua tahap, yaitu uji kecernaan C. racemosa dan uji pertumbuhan udang. Udang windu yang digunakan pada uji kecernaan berbobot 5,70 ± 0,42 g. Parameter uji yang diukur meliputi kecernaan total, protein, kalsium, magnesium, dan energi. Uji pertumbuhan dilakukan menggunakan rancangan acak lengkap dengan empat perlakuan dan tiga ulangan, yaitu penggunaan tepung C. racemosa sebesar 0 (kontrol), 10, 20, dan 30%. Udang windu dengan bobot 0,36 ± 0,02 g dipelihara dalam wadah kontainer plastik ukuran 70×45×40 cm (volume air sebanyak 90 L) dengan kepadatan 15 ekor tiap wadah selama 42 hari. Hasil penelitian menunjukkan kecernaan total C. racemosa pada udang windu 51,82%, kecernaan protein 88,67%, kecernaan kalsium 68,44%, kecernaan magnesium 16,39%, dan kecernaan energi 60,30%. Penelitian tahap kedua pada kinerja pertumbuhan udang yang mengonsumsi pakan mengandung 10% C. racemosa, tidak memberikan nilai yang berbeda nyata dengan udang yang mengonsumsi pakan kontrol. Namun, kinerja pertumbuhan udang menurun setelah mengonsumsi pakan yang mengandung C. racemosa di atas 20%, sedangkan aktivitas enzim superoxide dismutase (SOD) meningkat. Dari penelitian ini dapat disimpulkan bahwa penambahan C. racemosa ke dalam formula pakan sampai 10% dapat digunakan sebagai bahan baku pakan udang windu.
Kata kunci: Caulerpa racemosa, Penaeus monodon, kecernaan, kinerja pertumbuhan, udang
This study determined the minimum dietary level of fish meal (FML) and krill meal (KRM) and their mix ratio to elicit feed intake and growth performance in Penaeus vannamei . Ten diets were formulated with graded FML (90, 60, 30 g kg − 1 ) in combination with 15, 30, and 45 g kg − 1 KRM, and a control diet with 120 g kg − 1 FML. Shrimp (1.28 ± 0.08 g body weight, BW) were stocked in seventy 1-m ³ tanks (135 animals m − 2 ) and after 88 days their growth performance was determined. Feed preference was assessed through two-by-two comparisons in twenty 0.5-m ³ tanks over four weeks. No significant differences in survival (93.9 ± 4.5%), gained yield (1,235 ± 92 g m − 2 ), and feed conversion ratio (1.47 ± 0.09) were observed. Diets with 60 g kg − 1 FML led to faster growth and higher feed intake than 30, 90 and 120 g kg − 1 FML. Shrimp on 30 g kg − 1 FML diets had the lowest BW, especially with 30 − 15 (FML-KRM) and 30–30 diets. Diets with 90 g kg − 1 FML outperformed 30 g kg − 1 FML. The control diet had higher body weight than diets 30 − 15 and 30–30, showing similar results to other diets except 60 − 15. Feed preference was influenced by KRM inclusion, with 15 g kg − 1 KRM resulting in higher apparent feed intake than 30 and 45 g kg − 1 . The findings indicate that higher levels of KRM and FML in combination do not contribute to greater feeding stimuli or enhanced growth performance. These results enable the reduction of their utilization, from 120 to 60 g kg − 1 FML and from 45 to 15 g kg − 1 KRM, while still stimulating feed intake and growth performance in whiteleg shrimp.
Pacific white shrimp (Litopenaeus vannamei), the most cultured crustacean in the world, has become one of the key species in the international aquatic trade accounting for 11.96% of the total aquaculture production value in 2020. The development of the aquafeed industry, especially the large-scale use of fish meal (FM) and fish oil, contributed to promoting the expansion of shrimp production. However, the supply of FM has fluctuated at about 5 million tons per year affected by the El Nino during the last decades. This finite supply in combination with continued demand contributes to high prices, prompting the development and use of alternative protein sources. This review contributes to the development of appropriate FM replacement strategies in shrimp feed and summarises the status of research on alternative protein sources, including plant, animal and single-cell proteins in commercial feeds for Pacific white shrimp. Furthermore, several key aspects of nutritional balances were mentioned including amino acid profiles, fatty acid nutrients and trace elements in low FM diets as well as some easily overlooked concepts that deserve attention such as epigenetics, feed processing characteristics, animal growth stages, and shrimp species improvement. Also, the prospects of future research are proposed including the application of advanced technologies (16S rRNA sequencing, transcriptomics, proteomics and metabolomics), developments in the new feed additives, along with the optimisation of new protein sources and the establishment of a precise nutritional programming for shrimp.
Raw materials or bioactive ingredients trigger mechanisms to assimilate nutrients and activate metabolic pathways that promote growth, immune function, or energy storage. Our understanding of these processes at a molecular level remains limited in aquaculture, especially in shrimp. Here, hepatopancreas proteomics and haemolymph metabolomics were used to investigate the post-prandial response of black tiger shrimps (Penaeus monodon) fed a conventional fishmeal diet (FM); a diet supplemented with the microbial biomass Novacq™ (NV); krill meal (KM); or, fasted (FS). Using FM as a control, a 2-fold change in abundance threshold was implemented to determine the significance of proteins and metabolites. NV fed shrimp showed preference for energy derived from carbohydrates indicated by a strong signature of glycoconjugate metabolism and activation of the amino- and nucleotide sugar metabolic pathway. KM activated the glyoxylate and dicarboxylate pathway that denoted shrimp preference for lipidic energy. KM also influenced energy generation by the TCA cycle inferred from higher abundance of the metabolites succinic semialdehyde, citric acid, isocitrate, alpha ketoglutarate and ATP and downregulation of the enzyme isocitrate dehydrogenase that catalyses oxidative decarboxylation of isocitrate. FS shrimp displayed down-regulation of oxidative phosphorylation and resorted to internal lipid reserves for energy homeostasis displaying a strong signature of autophagy. Pyrimidine metabolism was the preferred energy strategy in this group. Our study also provided evidence that during fasting or consumption of specific ingredients, shrimp share common pathways to meet their energy requirements, however, the intensity at which these pathways were impacted was diet dependent.
Due to the precarious status of global fisheries the aquaculture sector has come under pressure to move away from its addiction to fishmeal (FM) and fish oil (FO) as feed ingredients, towards more sustainable alternatives. This chapter provides a brief overview of animal, microbial and plant-based feedstuffs that have been examined as FM/FO substitutes. Other than classic rendered meat products, attention is given to insect meals and issues surrounding their safety. Single celled products, including fungi and yeasts, bacteria, and microalgae are examined as sources of protein, lipid, pigments and enzymes. Plant-based proteins and lipid sources are also examined. Feed additives such as exogenous enzymes (phytases, lipases, proteases and carbohydrases) are evaluated as potential aquafeed ingredients as too are pigments, chemoattractants and palatants. Discussion is provided on pre-, pro- and synbiotics. Examples of the application of these various ingredients are considered with reference to over 50 species of cultivated organism.
Aquaculture, particularly protein-rich food for the world’s increasing human population, is the most reliable food supply in the future. On the other hand, poor practices and feed issues lead to illness susceptibility and, as a result, infections and disease outbreaks. A diet specially designed for their nutritional needs. This chapter provides information on animal feeds used in the aquaculture sector, primarily for finfishes and crustaceans. It mainly included the general importance and requirements of the nutritional compounds and common diet supplements of fish feed. Overview of the most common feeds, their role in aquaculture, the animal feeds used in hatcheries, and the nutritional quality of feeds in aquaculture, with particular attention to the most suitable and common feeds used in freshwater and marine aquaculture, is provided.
The present study was conducted to investigate the effects of Antarctic krill Euphausia superba meal replacing dietary fish meal on the growth performance, immunity and muscle quality of white shrimp Litopenaeus vannamei (initial body weight: 4.080 ± 0.143 g, mean±SD). The replacement levels were designed as 0%, 5%, 15%, 30%, 45%, 60%, 75% and 100%, respectively. After a 52-day feeding trial, results showed that the specific growth rate (P = 0.129) and feed intake (P = 0.217) of shrimp were not significantly affected. Feed conversion ratio (FCR, P = 0.000), protein efficiency ratio (PER, P = 0.000) and protein retention (PR, P = 0.000) were significantly affected with a quadratic positive trend for FCR, a linear and quadratic negative trend for PER and a quadratic negative trend for PR. The total haemocyte count (P = 0.307), respiratory burst (P = 0.168), activities of superoxide dismutase (P = 0.221) and glutathione reductase (P = 0.170) in serum were not significantly affected. While, malondialdehyde content (P = 0.000), acid phosphatase (P = 0.000) and alkaline phosphatase activity (P = 0.000) in serum were significantly decreased both in linear and quadratic trend. The carotenoid content in exoskeleton (P = 0.019) and pH in muscle (P = 0.000) were linearly increased. With the increasing replacement levels, n-3 PUFA content (P = 0.001) in muscle significantly decreased and n-6 PUFA (P = 0.000) increased. The ratio of essential amino acid to total amino acid (P = 0.000) and the inosinic acid content in muscle (P = 0.002) were significantly increased with the dietary replacement levels in a linear trend. In conclusion, Antarctic krill meal can totally replace dietary fish meal without negative impact on the growth of L. vannamei. From the perspective of feed utilization, after the quadratic regression analysis of FCR, PER and PR, the appropriate replacement level of dietary fish meal by krill meal for L. vannamei was 52.78%, 68.50% and 47.41%, respectively (i.e., dietary krill meal level was 13.27%, 17.22%, and 11.92%, respectively).
Somatic and expressional effects of replacing dietary fishmeal (FM) with a 1:1:2 combination of soy protein concentrate, corn gluten meal, and hydrolysate of forage-fish (HWF) or Pacific krill (HPK) were investigated in juvenile largemouth bass for 66 days. The control diet (FMC) contained 320 g kg⁻¹of FM. Six extruded diets were produced with 3 rates of replacement at 25 %, 50 % and 75 % protein for each of the two hydrolysate combinations. Feed intake (FI) and weight gain (WGR) did not differ between fish fed HWF diets and FMC. Fish fed HPK50 and HPK75 had lower FI and WGR. FI linearly decreased with increasing HPK, while feed conversion ratio (FCR) increased. No significance was found in the FCR among groups fed FMC, HWF25, HWF50, and HPK25, whereas HWF75, HPK50, and HPK75 groups had significantly higher FCR. The apparent digestibility (AD) of crude protein (CP) increased with increasing HWF while HPK didn’t cause significant change. AD of lipid and energy were not affected by diet, and AD of most amino acids increased proportionally with HWF. No proximate composition or retention of crude or digestible protein or energy other than whole-body ash revealed HWF-related differences. Whole-body CP, lipid, ash contents and CP retentions showed significant dose response in HPK fed fish. The condition factor decreased linearly with increasing HPK. Fish fed HPK50 diet upregulated peptide transporter 1 (pept1) expression in the foregut. Expressions of both taurine transporter (taut) and pept1 were upregulated by increasing replacement from 0 % to 25 % HWF. Further increase in HWF replacement caused linear down regulation in expression of both transporters. In conclusion, HWF and HPK facilitated reduced use of fishmeal in practical diet for largemouth bass. Expressions of pept1 and taut were dose-dependent in fish fed HWF. HPK just caused single diet upregulation.
The increasing market demand for decapods has led to a considerable interest in cultivating decapod species at a larger scale. Following the development of hatchery technologies, most research has focused on the development of formulated feeds for commercially farmed decapods once they enter the juvenile stages. The use of formulated feed for decapods at a commercial scale is still in the early stages. This is probably because of the unique feeding behavior that decapods possess: being robust, slow feeders and bottom dwellers, their feeding preferences change during the transition from pelagic larvae to benthic juveniles as their digestive systems develop and become more complex. The current practice of decapod aquaculture involves the provision of juveniles with food such as natural diet, live feed, and formulated feed. Knowledge of nutrient requirements enables diets to be better formulated. By manipulating the levels of proteins and lipids, a formulated feed can be expected to lead to optimal growth in decapods. At the same time, the pellet’s physical characteristics are important factors to be considered upon formulating commercially farmed decapod feeds, considering the unique feeding behavior of the decapod. However, most published studies on decapod nutrition lack data on the physical characteristics of the feed types. Thus, it is difficult to establish a standard feed formulation that focuses on the physical pellet properties. Moreover, careful consideration must be given to the feeding behavior of species, as decapods are known as bottom feeders and are robust in terms of handling feed. Information on the pellet forms, diet composition, and unique feeding behaviors in commercially farmed decapods is gathered to suggest potential better formulated diets that can optimize growth and reproduction. Thus, the purpose of this review is to summarize the information that has been published to date and to come up with suggestions on ways to improve the feed formulation in decapods that comply with their feeding behavior and nutrient requirements. Further research is needed to explore the potential of the pelleted feed at the adult stage so the decapod can take full advantage of the nutrients present in the pellets.
Brewer's spent grain (BSG) is the major byproduct generated by the brewing industry. It has 50–70% fiber and 14–30% protein contents. This study investigates the technical and economic performances for producing protein-rich product (PP) from BSG using enzyme-assisted fractionation process. This was done through process optimization, scale-up verification, and techno-economic analysis (TEA). The experiment was conducted with varying enzyme (Alcalase) loadings and enzymatic hydrolysis times. The results showed that the optimal condition was using Alcalase loading of 5 μL/g with hydrolysis time of 1 h for achieving a high protein concentration (46%) in PP and protein separation efficiency (80%). Using the optimal condition, the scaled-up process resulted in a consistent PP composition and protein separation efficiency. The experimental conditions and results were input into process simulation model for determining the mass and energy flows, from which TEA is derived. For a processing plant with a capacity of 590 t wet BSG per day, the minimum selling price of PP (MSPP) to achieve a 5% return was determined to be 1044 USD/t. Sensitivity analysis revealed that Alcalase and BSG costs have the most effect on the MSPP. Besides, protein separation efficiency is an important processing parameter in determining the MSPP.
There are several literatures that cover different views of crustacean food, feeding and behavior aspects, but little was known on its interaction between them and it's also shown a different perspective. Thus, a better understanding of the interactions between food, feeding and diets in crustaceans is vital for developing better quality of seed or broodstock produced in hatchery and its adaptation to the aquaculture environment and system. The aim of the present review is to update the state of the art and to explicit the knowledge regarding food, feeding and diets in crustaceans and challenges and opportunities in the development of formulated diets.
This study aimed to investigate the effect of acidifying the diet of black tiger shrimp Penaeus monodon on its growth and feed efficiency by supplementing coconut sap vinegar CSV) or sugar cane vinegar (SCV) or their 1:1 combination. Three hundred and sixty post larva shrimps (average initial weight of 0.01g) were randomly distributed into 12 50-L plastic containers. Four experimental diets, namely, control diet, 2% CSV, 2% SCV and 2% CSV+SCV were fed to groups of shrimps. After 90 days, all shrimps fed with diets containing vinegar exhibited significantly higher final average body weight (FABW), weight gain (WG), feed intake, specific growth rate (SGR), and better feed conversion ratio (FCR) than those fed the control diet. Attractability tests showed that the CSV and CSV+SCV diets attracted significantly the highest percentage of shrimps after 10 min of feed placement. Survival rate was not significantly different among the treatments. In conclusion, the results demonstrated that the vinegars tested could be used as growth enhancers in shrimp and that the combination of coconut sap and sugar cane vinegars supplemented to the diet resulted in the best growth and feed efficiency as well as attracted the most percentage of shrimps. Produced by the AquacultureHub non-profit Foundation the IJA is an open-access, scientific journal, published on http://www.aquaculturehub.org/group/israelijournalofaq uaculturebamidgehija To read papers free of charge, please register online at the above website. Sale of IJA papers is strictly forbidden. 2 dela Calzada et al.
In shrimp farming, there has been a considerable focus on the development of novel additives that might reduce costs associated with the time taken by shrimp to locate and ingest feed. However, within these trials there has been little consideration of the role that feeding behaviour of individuals can play in assessing the attractability of additives. As such, the use of tracking technologies in the development of automated protocols is beginning to gain attention as an important tool for monitoring associated behaviours. Therefore the objective of the present study was to validate an automated tracking software (EthoVision) for assessing feed attractability in Pacific white shrimp (Litopenaeus vannamei). Twenty-seven juvenile shrimp (5.54 ± 1.37 g) were used to test three experimental diets with different theoretical levels of attraction; negative (0.07 M Quinine-HCl), control, and positive diet (3% attractant). Shrimp were individually video recorded in test arenas for 20 min with each one of the diets. Recordings were also carried out at two times of day (morning and afternoon) to evaluate the effect of time of day on shrimp feeding behaviour. The behaviour of each individual was recorded three times per diet to determine levels of individual variation. Comparison between manual and automated observations validated the reliability of EthoVision in analysing L. vannamei feeding behaviour and the software detected clear differences in feeding behaviour according to diet. Shrimp provided with the positive diet (i.e. 3% attractant) arrived faster and spent longer on the feeding area. In contrast, with the negative diet (i.e. 0.07 M Quinine-HCl), shrimp spent more time moving around the test arena and less time interacting with the feed. Time of day also had an effect on several behaviours, but not on the time spent on the feeding tray. Less individual variation in feeding behaviours was found when shrimp were fed the positive diet, suggesting attractive diets can decrease variability in feeding behaviour with potential applications to commercial ponds. Distribution heatmaps provided by EthoVision offered a quick and reliable assessment of feed attractability. The results of this study highlight the use of tracking technologies to assess feed attractability in L. vannamei and the feasibility of automated protocols for the industry.
A protein‐rich product (PP) with 46% protein and less than 1% fibre was recovered from brewery's spent grain. This study aimed to investigate the effects of replacing dietary fishmeal with PP on the growth, feed utilization efficiency and nutritional composition of Pacific white shrimp, Litopenaeus vannamei. The control diet (PP0, containing 35% fishmeal) was compared with four isonitrogenous (44% crude protein), isolipidic (10% crude fat) and isocaloric (20 kJ/g) test diets, PP10, PP30, PP50 and PP70, which were formulated using PP protein to replace 10%, 30%, 50% and 70% of fishmeal protein. Sextuplicate groups of shrimp (averaging 1.10 g) were fed each of the five diets for 8 weeks. The results showed that up to 50% of fishmeal replaced with PP did not negatively affect the shrimp survival, growth performance, feed utilization efficiency, or the protein content and amino acid profile of shrimp. However, replacing 70% of fishmeal protein with PP protein negatively affected the percent weight gain and specific growth rate of shrimp, although the shrimp survival rate and feed conversion ratio were not affected.
P. monodon juveniles were fed krill meal (KM), krill hydrolysate (KH), whole squid (SQ), and the microbial biomass, Novacq™ (NQ), at 10% inclusion, in practical fishmeal and soybean meal based diets. Diets were fed to apparent satiation as well as restrictively pair-fed (~60% of control diet satiation) for 6 weeks to examine the effects of the test ingredients and feed restriction on shrimp growth, feed efficiency, digestive enzyme activity, nutritional condition, and gut microbiota.
All diets when fed to satiety significantly outperformed the control diet, with shrimp fed NQ 87%, SQ 73%, KH 41% and KM 38% larger than shrimp fed the control diet. NQ fed shrimp had the best feed conversion ratio (FCR) and significantly improved retention efficiency (RE) of dietary lipid (RETL), protein (RECP) and gross energy (REGE). SQ significantly promoted feed intake over control and KM fed shrimp, but neither KM, KH nor SQ improved RETL, RECP or REGE. While there was little change in the apparent digestibility (AD) of each diet, the apparent biological value (ABV) of lipid (ABVTL), protein (ABVCP) and gross energy (ABVGE) were significantly improved by inclusion of NQ; and ABVTL and ABVGE were significantly improved by addition of SQ. Feed restriction had a stronger effect on hepatopancreas digestive enzymes and gut microbiota than addition of any feed ingredient. Total protease activity was positively correlated with feed efficiency, including FCR, RETL and REGE. Shrimp fed to satiety tended to have high levels of Vibrio whereas those on the restricted ration tended to have higher levels of bacteria in Rhodobacteracaea, Flavobacteriales and Bacteroidales.
We conclude that shrimp are more efficient in using digested dietary macronutrients for growth when whole squid and Novacq™ are provided, due to improvements in feed intake and post-absorptive processes. Feeding restriction was shown to be a useful strategy to improve P. monodon feeding efficiency, digestive capacity and modulate gut microbiota, however it reduced the scope for shrimp growth especially on high performing diets. Novacq™ was more effective than some of the known invertebrate meals and a more environmentally sustainable growth and nutrient utilisation promoter for shrimp.
Three feed materials, fish meat (from oil sardines) paste, squid mantle paste and clam meat (Meritrix sp.) paste, and three chemical compounds, trimethyl amine, trimethyl amine oxide, and dimethyl sulphone were evaluated for their attractant and growth promoting properties for Penaeus monodon. The materials were individually incorporated in a semi-purified diet consisting of casein (40%) and gelatin (10%), fish oil (6.0%) and bread flour (33%) along with vitamins, minerals, filler and binder at specific levels ; while the natural materials were included each at 0.5% (on dry matter basis), the other compounds were incorporated at 0.01% level. The shrimp approached the diet containing dimethylsulphone (DMS) in the quickest time of less than 5 minutes on an average, followed by the diet with trimethylamine oxide (TMO) in 7.2 minutes. These are followed by trimethyl amine (TMA) to which diet the shrimp approached and picked up in 14.2 minutes. Among the natural materials tested, the diets containing fish meat paste (FMP), clam meat paste (CMP) showed better attractant property. The results showed that the materials tested elicited positive response as feed attractants with varying degree. The results also showed that DMS and TMO seem to possess the highest attractant property to the shrimp. Consumption of diet increased with feed additives, compared to the control diet with TMO and DMS diets recording the highest consumption. The feed additives tested also resulted in growth enhancement of shrimp.
Analyses of the free amino acids, quater-nary amines, guanido compounds, nucleotides, nu-cleosides, and organic acids in extracts of tissues from 10 species of marine teleost fishes and 20 species of invertebrates are reported. With multidimensional scaling techniques, the relative concentrations of the above chemicals in fishes, molluscs, and crustaceans are shown to cluster into separate taxon-specific groups. The greatest differences are between the fishes and the two groups of invertebrates. Similarities are more evident between the molluscs and crustaceans where eight of the nine most abundant substances are identical: i.e., betaine, taurine, trimethylamine oxide, glycine, alanine, proline, homarine, and arginine. The major tissue components in the fishes and invertebrates are correlated with compounds previously shown to stimulate feeding behavior in 35 species of fish. Glycine and alanine are major tissue components and are also the two most frequently cited feeding stimulants in the 35 species. Molluscs and crustaceans each contain high concentrations of five of the most frequently cited stimulants (glycine, alanine, proline, arginine, and be-taine); these substances all occur in much lower con-centrations in fish. Some minor tissue components, such as tryptophan, phenylalanine, aspartic acid, va-line, and uridine 5'-monophosphate, are, however, important feeding stimulants for some fish species. Stimulants for herbivores and carnivores are often dif-ferent. Several major feeding stimulants are substances that serve as "compensatory solutes," stabilizing en-zymes and structural proteins.
The production of the Pacific white shrimp (Litopenaeus vannamei) has expanded to the point of being the most widely cultured species of shrimp. One of the advantages of this species is its acceptance of a wide variety of feed formulations including plant‐based feeds. Given the increases in ingredient costs, particularly fish meal, there is considerable interest in the use of alternative feed formulations for cultured species. Given that soybean meal is one of the most widely available protein sources for which production can be expanded, the move to soy‐based diets is inevitable. The successful use of alternative feed ingredients for shrimp production depends on a number of factors. This paper summarizes studies regarding the move towards high soy diets concerning manipulation of ingredients and nutrient profiles to maintain balanced feed formulations.
A review is provided of the chemical components in tissue extracts that elicit feeding behavior in marine fish and crustaceans. For most species, the major stimulants of feeding behavior in excitatory extracts are an assemblage of common metabolites of low molecular weight including amino acids, quaternary ammonium compounds, nucleosides and nucleotides, and organic acids. It is often mixtures of substances rather than individual components that account for the stimulatory capacity of a natural extract. Recent studies using a shrimp,Palaemonetes pugio, are described in which behavioral bioassays were conducted with complex synthetic mixtures formulated on the basis of the composition of four tissue extracts. These results indicate that synergistic interactions occur among the mixture components. The neural mechanisms whereby marine crustaceans receive and code information about chemical mixtures are also reviewed. Narrowly tuned receptor cells, excited only by particular components of food extracts such as specific amino acids, nucleotides, quaternary ammonium compounds, and ammonium ions, are common in lobsters and could transmit information about mixtures as a labeled-line code. However, since physiological recordings indicate that most higher-level neurons in the brain each transmit information about many components of mixtures, rather than about a single component, it is suggested that information about a complex food odor is transmitted as an across-fiber pattern, instead of a labeled-line code. Electrophysiological recordings of responses of peripheral and central neurons of lobsters to odor mixtures and their components reveal that suppressive interactions occur, rather than the synergistic interactions noted earlier in the behavioral studies. Possible reasons for these differences are discussed. Evidence from the behavioral study indicates that the "direction" of a mixture interaction can be concentration-dependent and the synergism may occur at low mixture concentrations, while suppression may occur at high concentrations.
Reduction or elimination of fish meal and fish oil from aquaculture diets can help to reduce the potential for contamination and dependence of the industry on pelagic fisheries while improving economic competitiveness. However, fish oil provides important omega-3 (n-3) fatty acids (FAs) essential to shrimp health and beneficial to humans. This study evaluated an organic, plant-based diet formulated to replace fish meal and fish oil with plant proteins and docosahexaenoic acid (DHA) produced by algal fermentation. Shrimp cultured in replicate outdoor ponds at 25/m2 were fed either a diet composed of organically produced plant ingredients or a conventional commercial fish-meal- based feed. No significant differences were found in production parameters between the conventional fish-meal-based diet and the plant-based diet (production: 4594 and 4592 kg/ha; harvest size: 18.7 and 19.2 g; survival: 93 and 88%; and feed conversion ratio: 1.4 and 1.3, respectively). At harvest, shrimp were analyzed for 147 chemical contaminants and 71 FAs. Contaminant levels were negligible for shrimp raised on both diets. The fish meal and fish oil diet provided significantly higher quantities of eicosapentaenoic acid and DHA than the plant-based diet, and the shrimp fed the conventional diet
We are studying chemoattractants for the shrimp, Palaemonetes pugio, to identify the active components of stimulatory food extracts, and to determine whether the mixtures of substances occurring in extracts express themselves in an additive or an interactive manner. The results of quantitative analyses of the specific amino acids, quaternary ammonium compounds, organic acids, nucleotides and related substances in extracts of four organisms (crab, shrimp, oyster, mullet) were used to formulate artificial mixtures based on the composition of each organism. Quantitative behavioral bioassays with P. pugio showed that the artificial mixtures based on the composition of the crab and shrimp extracts were virtually as effective as the respective natural extracts, whereas artificial mixtures based on the composition of the oyster and mullet extracts were far less effective. Since the same types of substances were included in all of the mixtures, it is apparent that the substances serving as chemoattractants in different extracts are not constant but can vary depending upon the source of the extract. To examine for interactions among the components of the four artificial mixtures, responses to the mixtures and to their individual components were analyzed using the additive methods of stimulus summation and response summation. Synergistic interactions were evident since each mixture was markedly more effective than predicted on the basis of these additive models. The degree of synergism varied with the composition of the mixture.
Shrimp production worldwide has increased dramatically, and optimal sites are no longer abundant. New farms are being constructed in areas where water salinity and ion composition are suboptimal. Aquaculturists and feed suppliers are attempting to alleviate ion nonequilibriums through nutrition. One nutritive supplement that has been marketed is the amino acid betaine. The present work evaluated the effects of betaine as a feed supplement on the survival and growth of Pacific white shrimp Litopenaeus vannamei reared at extreme salinities (0.5 or 50‰). Juvenile Pacific white shrimp (mean individual weight, 0.18 g) were reared in 16 tanks: eight tanks held water at 0.5‰, and eight held water at 50‰. Shrimp were maintained for 8 weeks in four replicate tanks from each salinity treatment and offered feed with or without a betaine supplement. Survival (75–89%) and final weights (2.8–3.5 g) were typical for this species reared in indoor systems, but there was no significant influence of the presence of betaine. However, there was a significant influence of salinity on growth. These results suggest that betaine supplementation to practical diets designed for Pacific white shrimp does not improve production at extremely low or high salinities.
A feeding experiment was conducted to determine the effect of the feeding attractant, glycine betaine (betaine hydrochloride) on the growth and feed conversion of juveniles of Macrobrachium rosenbergii (deMan) (mean initial weight 1.12 g). Three types of diets were prepared with the incorporation of glycine betaine at 5, 10 and 15 g kg−1 levels along with an unsupplemented control. After 60 days, weight gain, feed intake and food conversion ratio (FCR) were higher in prawn fed the three glycine betaine-added diets compared with the control feed. Among the glycine betaine-added diets, prawn fed glycine betaine at 5 g kg−1 level showed highest weight gain (2.73 g) by registering 61.5% increase in growth over control and also higher feed intake (5.79 g) and good FCR (2.12). There were highly significant differences (P < 0.01) in weight gain, feed intake, per day growth and FCR among treatments. There was no significant difference (P > 0.05) in survival among treatments.
Decapod crustaceans such as blue crabs possess a variety of chemoreceptors that control different stages of the feeding process. All these chemoreceptors are putative targets for feeding deterrents that cause animals to avoid or reject otherwise palatable food. As a first step towards characterizing the chemoreceptors that mediate the effect of deterrents, we used a behavioral approach to investigate their precise location. Data presented here demonstrate that chemoreceptors located on the antennules, pereiopods and mouthparts do not mediate the food-rejection effects of a variety of deterrents, both natural and artificial to crabs. Crabs always searched for deterrent-laced food and took it to their oral region. The deterrent effect was manifested as either rejection or extensive manipulation, but in both cases crabs bit the food. The biting behavior is relevant because the introduction of food into the oral cavity ensured that the deterrents gained access to the oesophageal taste receptors, and so we conclude that they are the ones mediating rejection. Additional support comes from the fact that a variety of deterrent compounds evoked oesophageal dilatation, which is mediated by oesophageal receptors and has been linked to food rejection. Further, there is a positive correlation between a compound's ability to elicit rejection and its ability to evoke oesophageal dilatation. The fact that deterrents do not act at a distance is in accordance with the limited solubility of most known feeding deterrents, and likely influences predator-prey interactions and their outcome: prey organisms will be attacked and bitten before deterrents become relevant.
Increasing economical and ecological concerns regarding the use of fish meal in diets for marine shrimp have led to the development of replacement strategies where soybean meal has received ample attention. Most studies evaluating these strategies have been carried out under laboratory conditions which greatly differ from production conditions in ponds. This study evaluated a fish meal replacement strategy using vegetable protein sources in practical feeds for marine shrimp reared in ponds. Juvenile Pacific white shrimp (Litopenaeus vannamei) (0.03 g) were stocked into 16 0.1-ha low-water exchange ponds and reared over an 18-week period. Four commercially extruded diets formulated to contain 35% crude protein and 8% lipids were evaluated. These diets included varying levels of fish meal (9, 6, 3, and 0%) which was replaced by a combination of increasing levels of soybean meal (32.5, 34.9, 37.2 and 39.6% respectively) and corn gluten meal (0.0, 1.7, 3.2, and 4.8% respectively) to replace the protein originating from fish meal. At the conclusion of the experimental period, there were no significant differences (P ≥ 0.05) in shrimp production among the test diets. Mean final yield, final weight, feed conversion ratio and survival values ranged from 5363–6548 kg ha− 1, 18.4–20.7 g, 1.38–1.12 and 84.0–94.0%, respectively. Although not significant, as higher levels of plant protein sources were included in the diets, the economic analysis showed a general increase in the partial gross returns of shrimp production. Results from this study demonstrate that fish meal can be completely replaced using alternative vegetable protein sources in practical shrimp feeds without compromising production and economic performance of L. vannamei reared in ponds.
The use of a co-extruded soybean poultry by-product meal with egg supplement was evaluated as a substitute for fish meal in a practical diet formulated to contain 32% crude protein and 8% lipid. The co-extruded product was substituted for menhaden fish meal on an iso-nitrogenous basis and offered to juvenile Litopenaeus vannamei (mean initial weight±standard deviation, 1.13±0.06 g) over a 6-week period. Inclusion levels ranged from 0% (30 g fish meal/100 g diet) to 100% replacement (0 g fish meal/100 g diet). A fifth diet was formulated to contain no fish meal and 1 g krill meal/100 g diet. Furthermore, a commercial shrimp feed was included in the study to allow for a commercial reference. At the conclusion of the growth trial, survival, final weight, percent weight gain and feed efficiency (FE) were not significantly different among treatments. The inclusion of krill meal did not appear to improve attractability or palatability of the diet. Co-extruded soybean poultry by-product meal with egg supplement appears suitable as a substitute for fish meal in L. vannamei diets.
This manuscript reviews the chemical ecology of two of the major aquatic animal models, fish and crustaceans, in the study of chemoreception. By necessity, it is restricted in scope, with most emphasis placed on teleost fish and decapod crustaceans. First, we describe the nature of the chemical world perceived by fish and crustaceans, giving examples of the abilities of these animals to analyze complex natural odors. Fish and crustaceans share the same environments and have evolved some similar chemosensory features: the ability to detect and discern mixtures of small metabolites in highly variable backgrounds and to use this information to identify food, mates, predators, and habitat. Next, we give examples of the molecular nature of some of these natural products, including a description of methodologies used to identify them. Both fish and crustaceans use their olfactory and gustatory systems to detect amino acids, amines, and nucleotides, among many other compounds, while fish olfactory systems also detect mixtures of sex steroids and prostaglandins with high specificity and sensitivity. Third, we discuss the importance of plasticity in chemical sensing by fish and crustaceans. Finally, we conclude with a description of how natural chemical stimuli are processed by chemosensory systems. In both fishes and crustaceans, the olfactory system is especially adept at mixture discrimination, while gustation is well suited to facilitate precise localization and ingestion of food. The behaviors of both fish and crustaceans can be defined by the chemical worlds in which they live and the abilities of their nervous systems to detect and identify specific features in their domains. An understanding of these worlds and the sensory systems that provide the animals with information about them provides insight into the chemical ecology of these species.
Aquaculture's pressure on forage fisheries remains hotly contested. This article reviews trends in fishmeal and fish oil use in industrial aquafeeds, showing reduced inclusion rates but greater total use associated with increased aquaculture production and demand for fish high in long-chain omega-3 oils. The ratio of wild fisheries inputs to farmed fish output has fallen to 0.63 for the aquaculture sector as a whole but remains as high as 5.0 for Atlantic salmon. Various plant- and animal-based alternatives are now used or available for industrial aquafeeds, depending on relative prices and consumer acceptance, and the outlook for single-cell organisms to replace fish oil is promising. With appropriate economic and regulatory incentives, the transition toward alternative feedstuffs could accelerate, paving the way for a consensus that aquaculture is aiding the ocean, not depleting it.
Extruded soybean meal (ESBM) was evaluated as a protein source for partial replacement of fish meal (FM) in diets of juvenile Litopenaeus vannamei. In the control diet (Diet 1), FM protein was replaced with increasing dietary levels of ESBM (4.28%, 8.40%, 12.62%, 16.82%, and 25.26%) at 10%, 20%, 30%, 40%, and 60% levels (Diets 2 to 6, respectively). An eight-week feeding trial was conducted on 720 juvenile shrimp (0.67 g ± 0.01 g mean initial weight), and nutrient digestibility of the six diets was determined. ESBM could replace 20% of FM without causing a significant reduction in growth of shrimp, but other dietary treatments strongly affected whole body composition. Crude protein content of the whole body fed Diet 6 was significantly lower than that fed Diet 2 (P < 0.05), while crude lipid content of the whole body fed Diet 5 or 6 was significantly higher than that fed Diet 2 (P < 0.05). Protein digestibilities of Diets 5 and 6 were significantly lower than that of Diet 1 (P < 0.05). Digestibility of lipids ranged from 96.97% in Diet 6 to 98.34% in Diet 3, whereas dry matter digestibility decreased with increasing replacement level. This study indicates that 20% FM replacement with ESBM in the basic diet containing 40% protein and 30% FM is optimal for juvenile L. vannamei.
A feeding experiment conducted with juvenile freshwater prawns in which betaine was added as a feeding attractant, resulted in a 17% increase in growth of the group that had chemoattractant augmentation following actual feeding. The chemoattractant was added to the water, in an aqueous concentrated solution of 10−3 M and induced a burst of food searching behavior leading to further consumption.
A simple and practical method for quantification of feeding stimulation of shrimp Litopenaeus vannamei was developed using feed preference as an index of comparison. Feed preference was defined as the percentage of shrimp observed in each feeding tray. Preliminary trials were undertaken with two commercial feeds (45% protein with 5% squid meal and 40% protein without squid meal). Results indicated the following criteria were suitable for use as methodology for evaluating feeding stimulation in 5-m diameter static flow tanks: shrimp density (2.5 shrimp/m2); observational period (1 or 2 h post-addition of feed to trays), feed rate (2%), and between-trial feed rate (2%). A further investigation was undertaken to evaluate the influence of protein level and source on feed preference using a basal diet consisting of wheat flour, casein, carboxymethyl cellulose binder, and limestone, with or without krill meal as a feeding stimulant. A significant difference was shown in feeding preference for the 16% protein/4% krill meal vs. one without krill meal; however, this relationship was not shown in 45% protein feed comparisons. A second trial comparing 0, 16,30, and 45 % protein/casein-based feeds showed similar results. From these findings, it was postulated that casein, itself, also serves as a feeding stimulant at high dietary inclusion levels. A third trial comparing 16% protein/casein or wheat gluten-based feeds Indicated a delay of at least 2 h in maximum feeding preference response in feeds in which 4% krill meal was added as a feeding stimulant. It was postulated that chemical stimulants from krill meal were more slowly released in wheat gluten-based feeds. Our methodology appears suitable for evaluation of potential feeding stimulants when incorporated into low-protein casein-based or wheat-gluten-based feeds.
The inclusion in feed formulations of ingredients that act as attractants and feeding incitants or stimulants has been proposed as a means of increasing feed consumption, and hence growth, of farmed shrimp. Squid, crustacean and krill meals, fish and krill hydrolysates and a betaine product (Finnstim) were examined to assess their relative effectiveness in increasing the feed intake of black tiger shrimp Penaeus monodon. These presumed feeding effectors were added to a base feed at between 5 and 50 g kg−1. Given a choice between the base feed and one containing one of the test ingredients, P. monodon showed a significantly greater preference for the feeds containing crustacean or krill meal. Four of the presumed feeding effectors were further evaluated in a growth response experiment. There was no significant difference in the amount the shrimp consumed of any of the feeds. However, the growth rate of the shrimp was about 20% faster on the feeds containing crustacean meal or krill meal. Although ingredients such as crustacean meal or krill meal can improve feed intake, in practical feed formulations that contain significant amounts of terrestrial protein but relatively low levels of marine ingredients, there does not appear to be need for additional feeding effectors. However, crustacean meal and krill meal do provide a significant nutritional benefit, as seen by the improved growth rates in this study.
A study was conducted to obtain a measure of the potency of some potential and commercially used feeding attractants for Penaeus monodon Fabricius. Behavioural trials monitoring the feeding response of the shrimp were used to gauge the attractant qualities of the substances. A growth trial recording the feed intake, feed assimilation, growth, food conversion and survival rates of the shrimp was used to assess further the feeding stimulant properties of the substances.
Replicate groups of juvenile shrimp were fed semi-purified diets containing 1·5% by weight of a range of potential feeding attractants.
In the behavioural trial, diets containing taurine and a yeast extract were found to be significantly preferred to the control and all other diets. However, none of the substances appeared to act as potent feeding stimulants, producing statistically similar feed intake and assimilation rates to the control diet. However, taurine and an amino acid mixture designed to mimic a clam extract promoted the best performance of the attractants tested in terms of growth rate and feeding efficiency.
Overall, the behavioural response of the shrimp to the feeding attractants was found to show similarities to the effects of attractant supplementation of feed on subsequent ongrowing performance, but not significantly so.
Litopenaeus vannamei were stocked in 25 clear-water 500-L tanks at 100 shrimp m−2 and in 25 green-water 1000-L tanks at 60 animals m−2. Four diets were formulated to include krill meal at 10, 50 or 110 g kg−1; or krill oil at 25 g kg−1 by replacing fish meal, fish oil, soybean lecithin and cholesterol. Diets had similar levels of crude protein, total energy and essential amino acids. After 72 days, shrimp reared in clear and green water showed no differences in performance among diets. In clear water, shrimp attained 13.1 ± 0.59 g body weight, 1.00 ± 0.06 g week−1 growth, 81.4 ± 7.3% survival, 780 ± 118 g m−2 yield, 16.9 ± 1.8 g shrimp−1 apparent feed intake (AFI), and 2.18 ± 0.29 food conversion ratio (FCR). In green water, shrimp attained 14.3 ± 0.81 g body weight, 1.04 ± 0.09 g week−1 growth, 91.4 ± 5.4% survival, 569 ± 69 g m−2 yield, 20.9 ± 3.2 g shrimp−1 AFI, and 2.22 ± 0.34 FCR. Diets containing krill meal or krill oil were able to fully replace the protein and lipid value of fish meal, fish oil, soybean lecithin and cholesterol at no cost to performance.
A feeding bioassay which uses agar discs was developed for evaluating chemosensory stimuli influencing ingestive behavior in Penaeus vannamei. Agar disc hardness and preventing the shrimp from placing their mouthparts directly onto the stimulus discs were important aspects of the bioassay design. The palatability assay required only small amounts of stimuli, was suitable for rapid screening of a wide variety of compounds, and was independent of factors such as texture or size of feed pellets. The most effective stimulus tested was shrimp-head offal extract, indicating the best use of this material may be as a flavorant rather than as a source of nutrients. Greatest biological activity was in the < 1000 M.W. fractions of the extracts.
Crustaceans utilize water-borne‘chemical signals’to identify and orient toward potential prey. These chemical signals are recognized in spite of the chemical complexity of aquatic environments. Because feeds are a significant expense in all aquaculture operations, the need to maximize feeding rates and reduce wasted feed, thereby lowering production costs, is paramount to economic success. Confusion concerning the function and utility of chemoattractants versus feeding stimulants in aquatic feeds necessitates updated terminology. Simply put, detection does not equal attraction. To accurately describe and predict responses to feeding stimuli, it is necessary first to classify all possible stimulus types and then to categorize behavioural responses to each specific stimulus. The proposed hierarchical behavioural model classifies an animal's response to chemical stimuli into five phases: (1) detection; (2) orientation; (3) locomotion or displacement; (4) initiation of feeding; (5) continuation or termination of feeding. The second step in description of the behavioural model is the association of specific behaviours with these five phases of response. Crustaceans exhibit four major categories of chemotactic behaviour: antennule flicking, which appears to be the most sensitive; probing movements made by the pereiopods that precede locomotion; locomotion by the crustacean, indicating true attraction or repulsion; and movements by the mouthparts that indicate generalized feeding stimulation. Finally, feed and environmental quality have direct effects on the effectiveness of feed attractants/stimulants; food detection and feeding stimulation ultimately determine the commercial value of an aquatic feed.
Development of a pelleted dry feed as an alternative to feeding fresh fishery by-catch is an environmental priority for tropical spiny lobster aquaculture. Earlier studies have shown the lobster's acceptance of pelleted dry feed diminishes rapidly after immersion in water. In this work, we quantified the rate at which dry matter, total protein, soluble protein and individual and total free amino acids were lost from pieces of green-lipped mussel Perna canaliculus, a commercially-extruded Penaeus japonicus (kuruma) shrimp feed (KSF) and four laboratory-made, fishmeal-based, pelleted feeds upon immersion for up to 7.5 h. The laboratory-made feeds contained homogenates of either green-lipped mussel, polychaete (Marphysa sanguinea), prawn (Metapenaeus bennettae) or squid (Sepioteuthis spp.). After being immersed in water for 0, 2.5 or 5 h, these same feeds were offered as a paired choice with KSF in two preference feeding studies with juvenile Panulirus ornatus lobsters. The loobster's preference for fresh mussel always exceeded that of KSF, irrespective of immersion time. Regression of the proportional intake of test feeds against the relative leach rate of KSF identified soluble protein, glycine and taurine as the principal leachate components having the highest positive correlations with the lobster's feeding preference.
Continued growth and intensification of aquaculture production depends upon the development of sustainable protein sources to replace fish meal in aquafeeds. This document reviews various plant feedstuffs, which currently are or potentially may be incorporated into aquafeeds to support the sustainable production of various fish species in aquaculture. The plant feedstuffs considered include oilseeds, legumes and cereal grains, which traditionally have been used as protein or energy concentrates as well as novel products developed through various processing technologies. The nutritional composition of these various feedstuffs are considered along with the presence of any bioactive compounds that may positively or negatively affect the target organism. Lipid composition of these feedstuffs is not specifically considered although it is recognized that incorporating lipid supplements in aquafeeds to achieve proper fatty acid profiles to meet the metabolic requirements of fish and maximize human health benefits are important aspects. Specific strategies and techniques to optimize the nutritional composition of plant feedstuffs and limit potentially adverse effects of bioactive compounds are also described. Such information will provide a foundation for developing strategic research plans for increasing the use of plant feedstuffs in aquaculture to reduce dependence of animal feedstuffs and thereby enhance the sustainability of aquaculture.
The feasibility of substituting soybean meal for fishmeal diets for juvenile white shrimp Litopenaeus schmitti (0.35±0.01 g) was evaluated, and an adequate substitution level was determined. Five diets were evaluated using 46%, 59%, 75%, 88% and 100% substitution levels. Pellet water stability was significantly affected by dietary soybean content (P<0.05). Increased soybean content produced lower pellet stability, ranging from a dry matter loss of 14–22% after a 2-h immersion, and 20–33% after an 8-h immersion. After 52 days, significant differences (P<0.05) were found in shrimp weight, feed conversion ratio and protein efficiency ratio. The values were 0.64–1.06 g, 2.8–7.9 and 0.45–1.21, respectively, for the three measurements. Overall, better results were obtained with diets where soybean meal was substituted for fishmeal up to 75%. The 100% soybean meal diet resulted in poor growth performance of shrimp. Survival rates were acceptable for all treatments (90% or higher) and no significant differences were found in survival between treatments. Regression analysis using the broken-line methodology indicated that 76.5±2% is an optimum soybean substitution level in diets that contained fishmeal and soybean as the major protein sources for grow-out of juvenile white shrimp.