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Effect of shrimp stocking density and graded levels of dietary methionine over the growth performance of Litopenaeus vannamei reared in a green-water system

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... Soybean meal (SBM), salmon meal, and soy protein concentrate were used as the main protein sources, with dietary inclusions of 380.0, 120.0, and 50.0 g kg −1 (as-is), respectively. The feed was supplemented with l-lysine, dl-methionine, and l-threonine in order to meet the minimum levels of these amino acids (AAs) required to maximize shrimp growth under green-water culture conditions (Façanha et al. 2016(Façanha et al. , 2018Nunes et al. 2019b). Total lysine, methionine (Met plus cysteine, Cys), and threonine reached 21. 49, 7.58 (13.69), and 17.87 g kg −1 of the diet (dry matter basis, DM), respectively ( Table 2). ...
... The chemical composition was determined for the feed, grain pellets (non-fermented and fermented), harvested shrimp (whole animal including the carapace, 15 animals per dietary treatment), and natural food (five samples per dietary treatment). For the purpose of this work, the algal material, feed remains and detritus attached to the interior walls above the water surface of rearing tanks is collectively called natural food (Façanha et al. 2016). After water from the tanks were drained, this organic material was scrapped from each tank and washed with distilled water to remove excess salt for proximate composition. ...
... However, in general, proximate composition of both natural food and shrimp whole body was not substantially altered with the different proportions of feed to FGP. Similar results were found by Façanha et al. (2016) when investigating the effect of graded levels of dietary Met (4.8, 6.2, 7.2, 8.1, or 9.4 g kg −1 of the diet, DM basis) and shrimp stocking density (50, 75, and 100 shrimp m −2 ) over the growth performance of juvenile L. vannamei. Authors reported that under a greenwater culture system, natural food composition (CP, Met, Met + Cys, and total EAAs) collected from the inner walls of outdoor tanks did not seem to respond to the dietary Met content and shrimp stocking density. ...
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This study investigated the dietary contribution of fermented grain pellets (FGP) to the growth of juvenile Litopenaeus vannamei raised in a biofloc-based system. Grain pellets made of agricultural plant by-products were fermented with distilled water containing dehydrated live probiotic yeast, Saccharomyces cerevisiae. Shrimp were fed a feed with 396.8 g kg⁻¹ crude protein (CP) under the following proportions: 100:0 (percentage of feed and FGP to the total daily ration, respectively), 75:25, 50:50, 25:75, and 0:100. Juvenile shrimp of 1.15 ± 0.12 g were stocked under 133 animals m⁻² and reared for 77 days in thirty-five 1-m³ outdoor tanks. Final shrimp survival reached 89.3 ± 5.7% and was unaffected by dietary treatment. Shrimp body weight decreased significantly from 12.68 ± 1.48 (100:0) and 11.71 ± 0.67 g (75:25) to a low of 5.23 ± 0.40 g (0:100). No differences were found in weekly shrimp growth between shrimp fed under 100:0 (1.06 ± 0.14 g) and 75:25 (0.97 ± 0.06 g). Feed replacement at 25% caused no loss in yield (1,290 ± 87 g m⁻²) compared to no feed replacement at all (1,365 ± 148 g m⁻²). The 75:25 proportion of feed to FGP was able to partially spare feed inputs leading to 0.08 USD kg⁻¹ savings in feeding costs. Results indicated that a feed replacement of 25% compensated by an equivalent amount of FGP as part of the daily ration led to no detriment in shrimp growth performance in a biofloc-based system.
... Dietary AA deficiency can negatively impact shrimp growth performance in intensive systems even under the presence of naturally available food sources. Façanha et al. (2016) evaluated graded levels of dietary Met (M + C) for juvenile L. vannamei of 1.97 ± 0.14 g stocked under 50, 75 and 100 shrimp m −2 in a green-water rearing system. Authors reported that maximum shrimp growth was achieved with a dietary Met (M + C) content between 0.72 (1.19) and 0.81% Met (1.28% M + C, % of the diet, DM basis). ...
... They implied that higher or lower dietary levels of Met (M + C) may be required depending upon natural food availability. In our study, Met (M + C) levels in experimental diets were much lower than those reported by Façanha et al. (2016) with a range of 0.36 (0.62) and 0.55 (0.88%). Therefore, it is clear that our diets were deficient in Met (M + C) and limiting levels resulted in suboptimal shrimp growth performance despite the presence of biofloc. ...
... The observed Met (M + C) content of biofloc in our study fell between 0.11 and 0.28% (0.20-0.46%). This is lower than the natural food analyzed by Façanha et al. (2016). Authors worked in the same rearing system, but with green-water in limited water-exchange conditions. ...
Article
Studies have demonstrated that biofloc can be used as food or as a nutrient source for farmed shrimp, either through direct intake from culture water or as an ingredient. We investigated the nutrient value and contribution of biofloc to the growth of L. vannamei fed essential fatty acid (EFA)- and amino acid (EAA)-restrained diets. A total of 6144 shrimp of 3.04 ± 0.43 g body weight (BW) were reared in 48 outdoor tanks of 1 m³ under 128 animals m⁻³ and fed 12 diets during 72 days in a biofloc-dominated system. Diets contained 31.54 ± 0.98% crude protein (CP, % dry matter basis) and 7.91 ± 0.46% total lipids. Dietary EFA and EAA were manipulated by progressively reducing the inclusion of fish oil from 2.00 to 1.00 and 0%, and fish meal from 12.00 to 8.00, 4.00, and 0%, resulting in a 3 × 4 fish oil-fishmeal factorial design (diets 2–12, 2–8, 2–4, 2–0, 1–12, 1–8, 1–4, 1–0, 0–12, 0–8, 0–4, and 0–0; % of the diet; as-fed). The relative contribution of biofloc and diets to shrimp growth was estimated using the stable carbon isotope (δ¹³C) mass spectrophotometry analysis. At harvest, shrimp final survival (79.4 ± 7.3%), yield (1407 ± 125 g m⁻³), FCR (1.88 ± 0.18), and AFI (20.6 ± 0.3 g of diet stocked shrimp⁻¹) were unaffected by dietary treatment. However, weekly growth was significantly lower with diets deprived of fish oil and containing lower levels of fish meal (0 and 4%) compared to higher levels (8 and 12%). Shrimp BW was significantly affected by the dietary inclusion of both fish oil and fish meal and their interaction, varying from 13.08 ± 0.72 (diet 0–0) to 14.82 ± 0.23 g (diet 2–12). Biofloc contained a high ash content (58.09 ± 3.01%), low lipid levels (1.67 ± 0.32%), and a 7.71–18.05% CP content. The isotopic signatures in shrimp muscle at harvest became more negative compared to values observed at stocking, approaching values of the diets used. We estimated that the experimental diets contributed on average with 91.5 ± 7.4% of the shrimp's carbon growth, with the remaining attributed to biofloc. Our results demonstrated that juvenile L. vannamei reared in a biofloc-dominated system derive the bulk of their nutrition and growth from artificial food. Biofloc acts as a supplemental food source, but provides a limited source of key dietary nutrients to shrimp growth.
... Increasing feed allowance in low-fish meal diets allows for a reduction in dietary methionine for juvenile... Façanha et al. Recent studies indicate that growth stage, stocking density, salinity, and water exchange regime have an effect on the amino acid requirements of penaeid shrimp (Duy et al., 2012;Façanha et al., 2016Façanha et al., , 2018Liu et al., 2014). However, compared with other production animals (e.g., swine and poultry), studies evaluating the interactions of non-dietary factors and nutritional requirements of farmed shrimp are scarce. ...
... Green-water systems operate outdoors for exposure to sunlight, which drives photosynthesis, development of naturally occurring food items, and daily variations in water quality. We have conducted several studies under these conditions (Façanha et al., 2016(Façanha et al., , 2018Nunes et al., 2019a,b), which showed that the dietary methionine (Met) content strongly interacts with shrimp stocking density, natural food availability, water exchange, and minimum level of dietary crude protein content for optimal shrimp growth. The higher the stocking density, the less available natural food becomes and the higher is the amount of dietary Met required to maximize shrimp growth (Façanha et al., 2016). ...
... We have conducted several studies under these conditions (Façanha et al., 2016(Façanha et al., , 2018Nunes et al., 2019a,b), which showed that the dietary methionine (Met) content strongly interacts with shrimp stocking density, natural food availability, water exchange, and minimum level of dietary crude protein content for optimal shrimp growth. The higher the stocking density, the less available natural food becomes and the higher is the amount of dietary Met required to maximize shrimp growth (Façanha et al., 2016). Conversely, limiting water exchange in a green-water system spares the requirement of dietary Met for juvenile whiteleg shrimp (Façanha et al., 2018). ...
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A 10-week study was conducted to evaluate the effect of feed allowance and graded levels of dietary methionine (Met) on growth performance of Litopenaeus vannamei. Juvenile shrimp of 1.83±0.14 g were stocked in 42 outdoor green-water tanks of 1 m3 under 120 shrimp m−2. Animals were fed under two feed allowances, regular and 30% in excess. Five diets with 30 g kg−1 fishmeal were designed to contain 318±2 g kg−1 crude protein and a minimum amount of protein-bound Met. To achieve graded levels of dietary Met, a control diet with 4.6 g kg−1 Met or 8.9 g kg−1 methionine + cysteine (M+C) was supplemented with 1.2, 2.2, 3.2, and 4.2 g kg−1 of DL-methionyl-DL-methionine to result in total dietary Met of 5.6, 6.9, 7.9, and 9.2 g kg−1 (10.0, 11.2, 12.1, and 13.5 g kg−1 M+C, respectively). A final survival of 86.5±3.6% was reached with no significant influence from feed allowance or dietary Met. Feed inputs significantly affected apparent feed intake, weekly shrimp growth, final body weight (BW), and gained yield. Larger meals and a higher dietary Met had no impact on feed conversion ratio. There was a significant interaction between feed allowance and Met over shrimp BW. By feeding animals in excess, BW was enhanced at 6.9 g kg−1 Met. A dietary Met of 7.9 g kg−1 was required to achieve a maximum BW under a regular feed allowance. Thus, shrimp required less amounts of dietary Met to maximize BW when higher feed inputs were delivered. Our findings demonstrate a sparing effect of dietary Met for L. vannamei when a higher feed allowance is adopted. Shrimp farmers should consider adjusting feed allowance to dietary Met to maximize shrimp growth performance and yield.
... AQUAVI ® Met-Met is the mixture of four different methionine stereoisomers (dl-Met-Met, ld-Met-Met, dd-Met-Met and ll-MetMet) which could be efficiently cleaved by digestive enzymes to free d-and l-methionine, and the higher bioavailability value than dl-Met has already been demonstrated in white shrimp (Façanha, Oliveira-Neto, Figueiredo-Silva, & Nunes, 2016;Niu et al., 2017;Xie et al., 2017). As shrimp are benthos feeders with slow feeding behaviour, part of supplemented methionine could be lost by leaching before ingestion ( Gu et al., 2013). ...
... Low dietary methionine content induced decreased growth performance of shrimp (Mamauag et al., 2012). Supplementing methionine in plant protein-based diets improved growth performance in many stud- ies among different species(Browdy, Bharadwaj, Venero, & Nunes, 2012;Façanha et al., 2016;Mamauag et al., 2012;Zhang et al., 2016).The SRs were not significantly influenced by different treat- ments; this result is in accordance with the study on dietary threo- nine requirement of white shrimp(Mingyan et al., 2009). However, the values were not high enough (around 80%), but no disease was found during the feeding trial. ...
... Experimental diets were designed as iso-ni- trogenous and iso-energetic, thus shrimp received equal protein and energy amount in all diets. This result is in accordance with Mamauag et al. (2012), as body proximate composition was not affected when red sea bream were fed with different forms of dietary methionine.Similar results were also obtained in protein reduction diets supple- mented with methionine and lysine for grass carp (Ctenopharyngodon idella) (Gan et al., 2012), and Met-Met-supplemented diets in white shrimp (Façanha et al., 2016). However, a high plant protein diet supple- mented with dl-Met or Met-Met affected the protein content of mus- cle while whole body moisture, lipid and ash contents were unaffected in white shrimp (Xie et al., 2017). ...
Article
A 10‐week feeding trial was conducted to evaluate the effects of supplementing different levels of dl‐methionyl‐dl‐methionine (AQUAVI® Met‐Met) in plant protein–based diets on Litopenaeus vannamei. The positive control (PC) and negative control (NC) diets were designed with 20% and 8% fishmeal respectively, and other six diets were formulated with graded levels of Met‐Met from 0.05% to 0.30% with a 0.05% increment on the basis of NC diet (MM 0.05–MM 0.3). Six replicates were randomly assigned to each diet with 50 shrimp each having initial weight of 0.98 ± 0.02 g. The variation of FM concentration from 20% to 8% and supplemented with graded levels of Met‐Met did not affect the survival rate, feed conversion ratio, protein efficiency ratio, whole body and muscle proximate compositions (p > 0.05). However, diets with ≤0.20% Met‐Met supplementation resulted in significantly increased weight gain and specific growth rate, after which both parameters reached plateau. Shrimp fed the NC diet showed significantly lower total essential amino acid (EAA) content in muscle (p < 0.05). Supplementation of Met‐Met significantly improved apparent digestibility coefficients of dry matter, crude protein, lipid, phosphorus and EAAs (p < 0.05). Based on broken‐line analysis, the methionine requirement for white shrimp was estimated to be 0.87% when using Met‐Met as methionine source.
... methionine (Met) + cysteine) depending on the culture system (outdoor static versus flow-through system, 70 shrimp/m 2 ; Façanha, Sabry-Neto, Figueiredo-Silva, Oliveira-Neto, & Nunes, 2018) and from 0.72 to 0.81% (1.19-1.28% Met + Cys) depending on stocking density (50-75 shrimp/m 2 ; Façanha, Oliveira-Neto, Figueiredo-Silva, & Nunes, 2016). However, given that Met is the first limiting AA in shrimp feed, it is important to further strengthen our knowledge on this subject. ...
... Diets were analyzed for dry matter (drying in a convection oven for 24 hr at 105 C) and CP (Dumas method of nitrogen estimation) following standard methods (AOAC, 2002). Determination of AA concentration in dietary ingredients and diets was carried out following procedures described in Figueiredo (Huai et al., 2009;Jin, Liu, Liu, & Zhang, 2017;Li et al., 2015;Liu et al., 2014;NRC, 2011;Zhou et al., 2012;Zhou, Wang, Wang, & Tan, 2013) and also on our past experience (Façanha et al., 2016(Façanha et al., , 2018. To balance other dietary EAAs while reducing CP content, diets were also supplemented with L-Lysine, L-Arginine, L-Threonine, L-Tryptophan, L-Phenylalanine, and L-Histidine. ...
... Four tanks were assigned for the CTL. The rearing system and water preparation were the same as that adopted by Nunes et al. (2011) and Façanha et al. (2016Façanha et al. ( , 2018. ...
Article
The use of supplemental essential amino acids (EAAs) has been shown to provide an opportunity to minimize excess levels of crude protein (CP) in animal feeds. The present study investigated the effect of reducing the amount of CP in low‐fish meal diets (5%) for juvenile Litopenaeus vannamei. Four sets of diets were prepared containing (% on a fed basis, mean ± SD) 31.24 ± 0.71, 33.70 ± 0.41, 36.90 ± 0.44, and 39.63 ± 0.14% CP, with each protein level containing a total dietary methionine (Met) (Met + Cys) level of 0.56 ± 0.02 (1.07 ± 0.23), 0.71 ± 0.01 (1.22 ± 0.20), 0.88 ± 0.02 (1.38 ± 0.22), or 1.04 ± 0.02% (1.55 ± 0.18%). Shrimp of 1.00 ± 0.08 g were stocked in 84 outdoor tanks of 1 m3 at a rate of 100 shrimp/m2 and raised for 75 days. Final survival ranged from 83 to 97% and was unaffected by Met content. Both survival and yield were significantly depressed when shrimp were fed the 31% CP diet. Shrimp grew at a weekly rate of between 0.79 and 0.97 g, achieving a final body weight (BW) in excess of 10.8 g. There was a significant interaction between CP and Met over BW. Shrimp fed 0.56% Met achieved the lowest BW at harvest. Increasing CP beyond 34% did not enhance BW. With a dietary Met content of 0.71%, the highest BW was achieved with 34% CP compared to other levels. There was a significant improvement in Feed Conversion Ratio (FCR) when CP was raised from 31 to 34%. Similarly, dietary Met levels above 0.71% resulted in a significantly better FCR compared to 0.56%. Our study has shown that, if dietary Met (Met + Cys) meets a minimum of 0.71% (1.22%), levels of CP could be reduced from 40 to 34% without adverse effects on shrimp performance.
... Organic acids, plant/algae extracts, nucleotides, functional amino acids, vitamins, and naturally occurring immunostimulant compounds such as β-glucans have been studied thoroughly in diets for fish and crustaceans, as they may improve growth performance, survival, stress, and disease resistance, as recently reviewed by Dawood et al. [6]. Their potential to be included in diets for juvenile and/or adult whiteleg shrimp has also been demonstrated to some extent by several authors [7][8][9][10][11][12][13][14][15][16][17][18]. Nevertheless, far fewer studies are available on the use of these supplements in diets for whiteleg shrimp initial developmental stages. ...
... Traditionally, methionine supply was ensured by fish meal, but continuous efforts are underway to reduce the industry dependence on this ingredient and replace it by plant-based proteins, where methionine and lysine are generally low in the amino acid profile. It has been shown by several authors that when dietary requirements are not met, generally, when low-fishmeal diets are concomitantly used, growth performances and survival of whiteleg shrimp can be affected [13,16,[38][39][40]. Additionally, methionine has a recognized role in the immune system and has recently been used to improve the antioxidant capacity, innate immune response, and/or disease resistance of whiteleg shrimp juveniles [16,18,41]. ...
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Dietary additives have the potential to stimulate the whiteleg shrimp immune system, but information is scarce on their use in diets for larval/post-larval stages. The potential beneficial effects of vitamins C and E, β-glucans, taurine, and methionine were evaluated. Four experimental microdiets were tested: a positive control diet (PC); the PC with decreased levels of vitamin C and E as negative control (NC); the PC with increased taurine and methionine levels (T + M); and the PC supplemented with β-glucans (BG). No changes in growth performance and survival were observed. However, post-larvae shrimp fed the NC had lower relative expressions of pen-3 than those fed the PC, suggesting that lower levels of vitamins C and E may impact the shrimp immune status. Lipid peroxidation levels dropped significantly in the BG compared to the PC, indicating that β-glucans improved the post-larvae antioxidant mechanisms. Furthermore, when compared with the NC diet, PL fed with BG showed significant increases in tGSH levels and in the relative expression of crus and pen-3, suggesting a synergistic effect between vitamins C and E and β-glucans. Amongst the additives tested, β-glucans seems to be the most promising even when compared to a high-quality control diet.
... Methionine (Met) is considered the most impacted essential amino acid (EAA) when fish meal is challenged. Recommended dietary Met levels in shrimp feeds have ranged between 0.7 and 1.0% of the diet (as-fed basis) depending on shrimp species (Penaeus monodon [43], Marsupenaeus japonicus [44]), source of supplemental Met [13,20,[45][46][47][48], growth stage [49], culture conditions (stocking density [50], water exchange regime [51], feed allowance [52]), and dietary protein level [53,54]. However, very little information is available on the optimal dietary Met levels in response to graded levels of fish meal in order to support maximum shrimp growth performance with economic efficiency. ...
... For the growth performance evaluation, an outdoor rearing system as described by Façanha et al. [50][51][52] and Nunes et al. [54] was used. The system consisted of independent 1.0 m 3 outdoor tanks (1.02 m 2 bottom area × 0.74 m height), each equipped with a perforated lid on the top to avoid shrimp from escaping. ...
Article
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This work investigated the optimal levels of fish meal (FML) and dietary methionine (Met) required for maximum growth performance of juvenile Litopenaeus vannamei with economic efficiency. Four sets of diets were prepared to contain 0.00, 6.00, 12.00 and 18.00% FML. Each set was supplemented with DL-methionyl-DL-methionine (DL-Met-Met) to result in a total dietary Met (Met + Cys) content of 0.58 (1.05), 0.69 (1.16), and 0.82% (1.29%), on a fed basis. Shrimp of 1.00 ± 0.08 g were stocked in 60 outdoor tanks of 1 m3 with 100 shrimp/m2, allowing five replications per dietary group. Shrimp in all the groups were fed 10 times daily for 70 days. In a subsequent trial, dietary protein and amino acid digestibility of four FML groups, but only at high dietary Met levels (~0.82%), were evaluated in 40 60 L indoor tanks (11 replicates per diet) for 93 days with 70 shrimp/m2. Final shrimp survival (92.85 ± 4.82%, mean ± standard deviation), weekly weight gain (1.17 ± 0.08 g), apparent feed intake (13.3 ± 0.5 g of feed per stocked shrimp), and feed conversion ratio (1.18 ± 0.06) were unaffected by dietary FML level and Met content. Gained yield was adversely affected when FML was reduced from 18 and 12% (1156 and 1167 g/m2, respectively) to 0 (1090 g/m2), but no change was observed at 6% (1121 g/m2). A significant interaction was detected between FML level and dietary Met. Under 0 and 6% FML conditions, higher levels of total dietary Met, 0.69 and 0.82%, respectively, were required to maximize shrimp BW. In comparison, at 12 and 18% FML, a dietary Met content of only 0.58% was sufficient. Overall, results indicated the use of FML can be minimized or completely eliminated without major detrimental effects on feed digestibility or shrimp growth performance, as long as proper supplementation of Met is carried out. Diets with 0 FML or with only 6% delivered the highest profit and return on investment compared to diets with higher levels.
... A deficiency in any one of these essential amino acid will slow down or halt the production of proteins that require that particular amino acid (Mente, 2006). For example, in the case of methionine, an essential amino acid with an important role in biological processes such as methylation and antioxidant properties besides its function in protein synthesis (Façanha et al., 2016 for revision), both AD1 and AD2 have 200% lower values when compared to CD3 and 200-400% lower values, than those available in formulated diets for C. quadricarinatus juveniles reported by Thompson et al. (2005). During vitellogenesis a significant decrease in methionine levels in hepatopancreas with an increase in the ovary is essential for growing oocytes and later embryos (Li et al., 2010). ...
... Jian) larvae (Chen et al., 2019). Façanha et al. (2016) also found enhanced Litopenaeus vannamei growth performance with supplemented food with 0.72 Letters "γ, δ, β" indicate significant differences among hepatopancreas, ovary, and cephalothorax (P < 0.05). Different lowercase letters indicate significant interaction between diets and organs (P < 0.05). ...
Article
The onset of sexual maturity represents a complex step in animal life involving morphological, physiological, and behavioral changes. From this point onward, the energy income from food will be involved in three energetic-demanding-competing processes: metabolism-homeostasis, growth, and reproduction. Hence, in cultured species formulated feeds need to cover all nutritional requirements of the growing phase and the additional cost demanded by reproduction. Two low-cost diets, AD1: 0.56 and 2 CE: 0.64 U$S kg⁻¹ manufactured with local supplies specifically formulated for Cherax quadricarinatus, were evaluated in a prolonged assay with females at the transition from juvenile to mature. Protein content was 440,2 and 380 g kg⁻¹ and lipid content was 134,8 and 114,9 g kg⁻¹ for AD1 and AD2, respectively. Females were obtained in the laboratory from our reproductive stock and were fed daily at 1.5% of their weight/day. The female mean initial total length was 6.5 ± 0.6 cm and mean body mass was 6.8 ± 0.7 g, which represents juveniles at the beginning of vitellogenesis. The experiment ended after three molting events when females achieved the full mature condition (⁓16–20 g). Somatic indices, growth, feed efficiency, biochemical composition of the ovary and hepatopancreas, ovarian growth, and histological alterations in hepatopancreas were analyzed. Both diets demonstrated that the high demands of both somatic and ovarian growth in maturating females were not covered, contrasting with previous results in early juveniles. This highlights the enormous energetic cost of vitellogenesis at the start of sexual maturity and the differential nutrients demand during crayfish growth. Biochemical analysis demonstrated a lower oocyte quality due to the experimental diets, as well as decreased reserves both of lipids and carbohydrates and a possible impact on carotenoids content. The hepatopancreas also showed partial histological damage and differences in its biochemical content. Although further analysis is required, lower embryo survival, hatching rate, and early performance of juveniles are expected in progeny from females fed with both diets. The low-cost diets tested are useful as a baseline from which modified formulations can be considered to achieve a more adequate composition enhancing somatic and gonad growth as well as feed efficiency in maturing females.
... Tyrosine, cyteine, and taurine are conditional or semiessential amino acids (NRC 2011;Yue et al. 2013). Several studies have investigated the requirement of lysine (Fox, Lawrence, and Li-Chan 1995;Millamena et al. 1998;Richard et al. 2010;Xie et al. 2012), methionine (Façanha et al. 2016;Fox et al. 2011Fox et al. , 2010Lin et al. 2015;Millamena, BautistaTeruel, and Kanazawa 1996b), and other amino acids (Chen, Leu, and Roelants 1992;Millamena, Bautista-Teruel, and Kanazawa 1996a;Teshima et al. 2002;Zhou et al. 2013) for shrimp. However, there is still controversy over the requirement and use of CAA by these species (Davis and Duan 2017). ...
... However, the one-way ANOVA did not show any significant differences in final weight, growth, and survival between the treatments, and therefore the basal diet may not have been deficient in methionine after all. Façanha et al. (2016) looked at the methionine requirement of Pacific white shrimp reared under a greenwater system at three different densities (50, 75, 100 shrimp/m 2 ). Diets were formulated with a methionine content to vary from 0.48% to 0.94% of the diet. ...
Article
In view of the variability in recommendations for essential amino acid (EAA) and the use of amino acids supplements in shrimp diets, this study was designed to evaluate the efficacy of crystalline amino acids (CAA) in practical shrimp feeds. The basal diet was designed to contain 30% protein and 6% lipid. The primary protein source of the basal diet included: 5% fishmeal, 37% soybean, and 5% gelatin. The intact protein was incrementally reduced to produce diets with 28%, 26%, 24%, and 22% protein. In a second series of diets, CAA were supplemented to the reduced protein diets to return the diets to 30% crude protein. Thus, producing a series of diets containing 30% protein with 2%, 4%, 6%, and 8% crystalline amino acids. The trial was conducted twice to confirm results. Data within treatments for both trials were variable, resulting in limited statistical differences. From a biological standpoint, percentage weight gain (PWG) and mean final weight (MFW) appeared to decrease with intact protein level of the diet (R² value [PWG], trial 1: 0.30, trial 2: 0.34, R² value, [MFW] trial 1: 0.44, trial 2: 0.38). None of the diets with supplemented CAA appeared to have reached the same MFW or PWG as the basal diet. Another trial was run using a fishmeal-based diet (30% CP), which in theory should be replete in all essential amino acids, and a soybean meal-based diet at two different protein levels (30% and 35% CP). The soybean meal-based diets were supplemented with essential CAA in one set and only methionine in another to reach the same level as a percent protein, compared to the fishmeal-based diet. No significant differences were observed between the diets in terms of PWG. However, the fishmeal-based diet seemed to outperform most of the other diets in terms of protein retention efficiency. Based on the results of these trials, it is questionable whether CAA are sufficiently utilized by shrimp.
... The nutrient requirements of L. vannamei have only been assessed in a few commercially relevant rearing systems differing in stocking density, salinity, and other water conditions [126][127][128][129][130]. The effects that different rearing conditions have on dietary requirements for many nutrients known to be required by L. vannamei, including fatty acids, some amino acids, vitamins, and minerals, have not been reported. ...
... Requirement studies may need to be specifically designed to assess the need for micronutrients within those conditions (likely lower levels of individual feed intake). This was demonstrated in a recent study where methionine inclusion levels to achieve maximum growth increased with stocking densities over the range of 50 to 100 shrimp m −2 [128]. An interaction exists between stocking density and methionine content driven by natural food availability, and this will likely impact the need for higher protein content when amino acid profiles are not supplemented with crystalline amino acids. ...
Article
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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.
... Most of these studies have, however, been focused on fish. For instance, dietary Met supplements have been shown to improve growth performance in different fish species (144,(154)(155)(156)(157)(158). Specifically, lack of Met in feed could affect protein synthesis and reduce feed utilization in flatfish (Solea senegalensis) and white bass (Morone chrysops) (159,160), as well as induce general mitochondrial dysfunction in liver of rainbow trout (Oncorhynchus mykiss) (161). ...
... Limited number of studies have explored the role of Cys and its metabolites in immune-metabolic modulation in crustaceans. Nonetheless, it has been shown that dietary Cys and Met supplementation improves survival rate, feed intake, and food conversion rate in P. vannamei (154). In the kuruma shrimp P. japonicus, Cys and GSH have been shown to improve growth, inhibit phenoloxidase (PO) activity, and reduce browning due to o-quinones (184). ...
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Aquaculture production of crustaceans (mainly shrimp and crabs) has expanded globally, but disease outbreaks and pathogenic infections have hampered production in the last two decades. As invertebrates, crustaceans lack an adaptive immune system and mainly defend and protect themselves using their innate immune system. The immune system derives energy and metabolites from nutrients, with amino acids constituting one such source. A growing number of studies have shown that amino acids and their metabolites are involved in the activation, synthesis, proliferation, and differentiation of immune cells, as well as in the activation of immune related signaling pathways, reduction of inflammatory response and regulation of oxidative stress. Key enzymes in amino acid metabolism have also been implicated in the regulation of the immune system. Here, we reviewed the role played by amino acids and their metabolites in immune-modulation in crustaceans. Information is inferred from mammals and fish where none exists for crustaceans. Research themes are identified and the relevant research gaps highlighted for further studies.
... There are several publications evaluating Met requirements for Pacific White shrimp (Façanha et al., 2016;Fox et al., 2011;Lin et al., 2015). There is differences in the requirement values and no clear definition of Met requirement value in shrimp provided in those papers, which suggested that Met requirement is affected by various factors such as developmental stage, production conditions (e.g., green water versus clear water), production intensity of shrimp [(0.72 (1.19% total sulfur amino acid) to 0.81% (1.28% total sulfur amino acid)] (Façanha et al., 2016), diet digestibility, source of supplemental Met (less than 0.4%) (Fox et al., 2011) as well as the use of statistical models (0.91% of diet or 2.28% of the protein in a diet with 0.5% cysteine) (Lin et al., 2015). ...
... There are several publications evaluating Met requirements for Pacific White shrimp (Façanha et al., 2016;Fox et al., 2011;Lin et al., 2015). There is differences in the requirement values and no clear definition of Met requirement value in shrimp provided in those papers, which suggested that Met requirement is affected by various factors such as developmental stage, production conditions (e.g., green water versus clear water), production intensity of shrimp [(0.72 (1.19% total sulfur amino acid) to 0.81% (1.28% total sulfur amino acid)] (Façanha et al., 2016), diet digestibility, source of supplemental Met (less than 0.4%) (Fox et al., 2011) as well as the use of statistical models (0.91% of diet or 2.28% of the protein in a diet with 0.5% cysteine) (Lin et al., 2015). ...
... Shrimp growth rate was shown to be significantly affected by the interaction between dietary Met (Met+Cys) content and stocking density, being highest (1.49 g/week) in shrimp fed diets containing 7.2 g of Met per kg of feed (11.9 g/kg Met+Cys, on a dry matter basis, DM) reared at 50 animals/m 2 . Yet, response of shrimp to dietary Met+Cys was less clear above 50 animals/m 2 , namely 75 and 100 animals/m 2 , and related with reduced weight gain and possibly feed restriction and crowding (Fac ßanha et al., 2016). ...
... The study was carried out with juveniles of the white shrimp, L. vannamei, reared in an outdoor green-water system (described by Fac ßanha et al., 2016). The work consisted in the evaluation of five diets formulated to contain graded levels of dietary methionine (Met), from 5 to 9 g/kg (10-14 g/kg Met+Cys, respectively; in a dry matter basis, DM). ...
Article
We examined if minimum water exchange could spare dietary methionine (Met) required for maximum growth performance of juvenile Litopenaeus vannamei reared in an intensive outdoor system. Shrimp of 1.98 ± 0.13 g were stocked at 70 animals/m² and reared for 72 days in 50 tanks of 1 m³ under flow-through (14.4% a day) and static (1.4%–2.9% a day) green-water conditions at 32.0 ± 3.7 g/L salinity. Five diets with a minimum inclusion of fishmeal supplemented with a dipeptide, dl-methionyl-dl-methionine, were formulated to contain increasing levels of Met, 4.8, 6.2, 7.2, 8.1 or 9.4 g/kg (on a dry matter basis). Each of the five diets were fed four times daily to five replicate groups. Dietary Met and water exchange significantly influenced shrimp survival, gained yield, apparent feed intake, food conversion ratio and final body weight (p < .05). Raising shrimp under limited water exchange, i.e., static versus flow-through spared the dependence on higher levels of dietary Met to maximize shrimp body weight, from 9.4 g/kg to 8.0 g/kg (14.0 and 12.6 g/kg Met+Cys respectively). In an intensive rearing system, a reduction in water exchange is desirable as it leads to a lower need for supplemental dietary Met.
... From the point of view of aquaculture in relation to larval farming: GWS are an aquaculture method using green water, which consists of microalgae or phytoplankton in order to improve the environment and nutrition of larvae of different marine families, such as various species of fish [30-37], octopus [38], crabs [39,40] and lobsters [41][42][43]. Also, different authors pay attention to the breeding of shrimps from natural feeding strategies produced endogenously [44][45][46][47][48][49][50][51][52][53][54][55][56][57][58]. The breeding of sea horses with microalgae paste replacing a clear water system [59]. ...
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Achieving Urban Flood Resilience (UFR) is essential for modern societies, requiring the implementation of effective practices in different countries to mitigate hydrological events. Green Water Systems (GWS) emerge as a promising alternative to achieve UFR, but they are still poorly explored and present varied definitions. This article aims to define GWS within the framework of sustainable practices and propose a regulation that promotes UFR. Through a systematic review of existing definitions and an analy-sis of international regulations on Sustainable Urban Drainage Systems (SuDS), the study reveals diverse perceptions and applications of GWS and their role in Blue-Green Infrastructure (BGI). The research proposes a standardized definition of GWS and their role in Blue – Green Infrastructure (BGI). The research proposes a standardized definition of GWS and the implementation of SuDS in Peru, addressing the current knowledge gap and contributing to the development of sustainable urban infrastructure.
... DL-MET and 0.15-1.7% for AQUAVI ® for better growth performance and feeding efficiency (Façanha et al. 2016, Xie et al. 2017, Nunes et al. 2019, Wang et al. 2019, Ji et al. 2021, Lu et al. 2021. Probiotic effects of ECOBIOL ® have also been studied in the water of biofloc system for farmed white shrimp, suggesting a dissolution of 2.8×10 3 CFU mL -1 (Llario et al. 2019) and 9.48×10 4 CFU mL -1 (Llario et al. 2020) for better growth performance and feeding efficiency. ...
Article
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An eight-week feeding trial investigated the effects of fishmeal (FM) replacement by soybean meal (SBM) and poultry by-product meal (PBM) in diets supplemented with two methionine sources (DL-Met and AQUAVI®) and their combinations with ECOBIOL® (Bacillus amyloliquefaciens CECT 5940) on growth performance, body composition, and nutrient metabolism of Penaeus vannamei. Four hundred shrimp (0.30 ± 0.04 g) randomly distributed into 20 tanks (20 shrimp tank-1) were fed with five experimental diets (four repetitions per diet). A control diet (CD; 20% FM) and four diets with 50% FM replacement supplemented with different methionine sources and ECOBIOL® combinations: D1 (0.13% DL-MET), D2 (0.06% AQUAVI®), D3 (0.13% DL-MET plus 0.10% ECOBIOL®), and D4 (0.06% AQUAVI® plus 0.10% ECOBIOL®). Shrimp fed D2 and D4 had better growth performance, nutrient utilization, and body composition. Shrimp fed D3 also had good growth performance but higher lipid body composition. Shrimp fed D1 had the worst growth performance, nutrient utilization, and body composition values. Nutrient metabolism-related genes were affected by dietary treatments. Protein synthesis-related genes decreased mostly in shrimp fed D1 and D2 while increased mostly in shrimp fed D3 and D4, lipolysis-related genes had a better transcriptional response in shrimp fed D4 and lipogenesis-related genes were mostly downregulated in shrimp fed D2 while were mostly upregulated in shrimp fed D3 and D4. Results suggested that FM could be partially replaced with SBM and PBM in shrimp feeds supplemented with 0.06% AQUAVI® alone or combined with 0.10% ECOBIOL® without adversely affecting the growth and nutrient metabolism of P. vannamei.
... The key to intensive farming is to stock animals at high densities, and this feature of the shrimp is in line with the current concept of transforming the aquaculture industry from "crude" to "intensive" (Rodríguez-Olague et al., 2021). However, being able to farm at high densities does not mean that shrimp are suitable for living at high stocking densities, instead changes in stocking density can impact on growth, immunity and metabolism of aquatic animals in many ways (AftabUddin et al., 2020;Apún-Molina et al., 2017;Façanha et al., 2016;Tang et al., 2018). Researchers have found that one possible reason could be that excessive stocking densities can stress the aquatic animal and force it to use the part of its energy that would otherwise be used for growth to respond to environmental stress. ...
... In addition, rainbow trout can suffer cataracts when fed on Met-deficient diets (NRC 2011). Exogenous Met supplementation in plant protein diets could improve growth performance in the whiteleg shrimp (Browdy et al. 2012;Façanha et al. 2016), red sea bream (Pagrus major) (Mamauag et al. 2012), Japanese seabass (Lateolabrax japonicus) , yellow river carp (Cyprinus carpio haematopterus) (Yun et al. 2022), African catfish (Clarias gariepinus) (Elesho et al. 2021), and gibel carp (Carassius auratus gibelio) (Ren et al. 2017). However, excessive Met could inhibit growth performance and feed utilization of hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂) (Li et al. 2020) and rainbow trout (Poppi et al. 2011). ...
Article
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This study evaluated the optimal DL-methionyl-DL-methionine (AQUAVI® Met-Met) supplementation for the red swamp crayfish Procambarus clarkii (initial body weight: 6.45 ± 0.12 g) fed plant-based diets. Seven diets were formulated, including a positive control with 50.0 g kg⁻¹ fishmeal (PC), a negative control with 77.6 g kg⁻¹ peanut meal replacing 50.0 g kg⁻¹ fishmeal (NC), and five experimental diets supplemented with 0.25, 0.50, 1.00, 2.00, and 4.00 g kg⁻¹ Met-Met. The analyzed Met-Met levels of the seven diets were 0.06 (PC), 0.10 (NC), 0.27 (M0.27), 0.46 (M0.46), 1.00 (M1.00), 1.99 (M1.99), and 4.10 g kg⁻¹ (M4.10), respectively. After a 6-week feeding, crayfish fed the NC diet had lower growth performance, protein deposition, digestive enzyme activities, and antioxidant capacity than those fed the PC diet (P < 0.05). With the increasing Met-Met level to 1.00 g kg⁻¹ in NC diet, the weight gain rate; specific growth rate; protein deposition rate; the activities of protease, lipase, and amylase in hepatopancreas and intestine; total antioxidant capacity; catalase and superoxide dismutase activities; and S-adenosyl homocysteine contents showed significant improvement (P < 0.05). This means the supplementation of 1.00 g kg⁻¹ Met-Met in the non-fishmeal diet could alleviate the negative effects caused by all-plant protein formulation. Based on the broken-line regression analysis of weight gain rate and protein deposition rate in red swamp crayfish, the optimal levels of Met-Met in an all-plant protein diet were 0.90 and 0.95 g kg⁻¹, and the levels of the total sulfur amino acid were 11.61 and 11.67 g kg⁻¹, respectively.
... Previous studies have evaluated the effects of reduced fishmeal diets supplemented with different dietary methionine sources on growth performance of L. vannamei, such as shrimp feed with 5% to 10% fishmeal and supplemented with a level between 0.15% and 1.7% of MET-MET (AQUAVI ® ) or 3% of DL-MET [2,3,8,20,42,43]. Nevertheless, a study with similar culture conditions that used juvenile shrimp (L. ...
Article
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An 8-week feeding trial investigated the effect of Fishmeal (FM) replacement by soybean meal (SBM) and poultry by-product meal (PBM) in diets supplemented with DL-Met, MET-MET (AQUAVI®), Bacillus amyloliquefaciens CECT 5940 (ECOBIOL®) and their combinations on growth performance and health of juvenile Litopenaeus vannamei. A total of six experimental diets were formulated according to L. vannamei nutritional requirements. A total of 480 shrimp (0.30 ± 0.04 g) were randomly distributed into 24 tanks (4 repetitions/each diet, 20 shrimp/tank). Shrimp were fed with control diet (CD; 200 g/Kg fishmeal) and five diets with 50% FM replacement supplemented with different methionine sources, probiotic (B. amyloliquefaciens CECT 5940) and their combinations: D1 (0.13% DL-MET), D2 (0.06% MET-MET), D3 (0.19% MET-MET), D4 (0.13% DL-MET plus 0.10% B. amyloliquefaciens CECT 5940 and D5 (0.06% MET-MET plus 0.10% B. amyloliquefaciens CECT 5940). Shrimp fed D3 and D5 had significantly higher final, weekly weight gain, and final biomass compared to shrimp fed CD (p < 0.05). Shrimp fed D2 to D5 increased the hepatopancreas epithelial cell height (p < 0.05). Digestive enzymatic activities were significantly increased in shrimp hepatopancreas’ fed D3 (p < 0.05). Meanwhile, shrimp fed D1 had significant downregulation of immune-related genes (p < 0.05). Moreover, shrimp fed D3 and D5 increased the abundance of beneficial prokaryotic microorganisms such as Pseudoalteromonas and Demequina related to carbohydrate metabolism and immune stimulation. Also, shrimp fed D3 and D5 increased the abundance of beneficial eukaryotic microorganism as Aurantiochytrium and Aplanochytrium were related to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) production which plays a role in growth promoting or boosting the immunity of aquatic organisms. Therefore, fishmeal could be partially substituted up to 50% by SBM and PBM in diets supplemented with 0.19% MET-MET (AQUAVI®) or 0.06% MET-MET (AQUAVI®) plus 0.10% B. amyloliquefaciens CECT 5940 (ECOBIOL®) and improve the productive performance, health, and immunity of white shrimp. Further research is necessary to investigate synergistic effects of amino acids and probiotics in farmed shrimp diets, as well as to evaluate how SBM and PBM influence the fatty acid composition of reduced fishmeal diets and shrimp muscle quality. Nevertheless, this information could be interesting to develop low fishmeal feeds for aquaculture without affecting the growth and welfare of aquatic organisms.
... Methionine is one of the essential amino acids for animals. Lack of methionine in feed can significantly reduce the growth of animals (Felipe et al., 2016;Zhang et al., 2019). In this experiment, the survival of sea cucumber juveniles was not affected by dietary methionine, but weight gain and specific growth rate were significantly increased by dietary methionine. ...
... In addition, the FCR increased with the increasing stocking density, which increases the cost of production. Similar results were observed in other studies that investigated the effect of stocking density on shrimp production (Moss and Moss, 2004;Esparza-Leal et al., 2010;Neal et al., 2010;Krummenauer et al., 2011;Sookying et al., 2011;Façanha et al., 2016;Araneda et al., 2020;Fleckenstein et al., 2020). However, survival of shrimp in our experiment was above 95%, while other researchers reported that survival decreased with increasing density (Neal et al., 2010;Krummenauer et al., 2011;Araneda et al., 2020). ...
Article
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Integrated aquaponic food production systems are capable of producing more food on less land using less water than conventional food systems, and marine systems offer the potential of conserving freshwater resources. However, there have been few evaluations of species combinations or operational parameters in marine aquaponics. The goal of this experiment was evaluation of stocking density ratio of Pacific whiteleg shrimp (Litopenaeus vannamei) to three edible halophytes (Atriplex hortensis, Salsola komarovii, and Plantago coronopus) with two C/N ratios in a 3 × 2 factorial design. There were three stocking density ratios (shrimp: plant), 2:1, 3:1, and 5:1; and two C/N ratios, 12 and 15. The results indicated that stocking density ratio exerted a significant impact on shrimp growth. Shrimp reared in 2:1 and 3:1 treatments had better growth performance. In contrast, plants were affected by both stocking density ratio and C/N ratio. Halophytes grown in stocking density ratios of 3:1 and 5:1 with a C/N ratio of 15 had better growth performance and nutrient content. The concentrations of TAN and NO2– were below 0.2 mg/L throughout the experiment, including the higher stocking density ratio treatments. In conclusion, the stocking density ratio of 3:1 with a C/N ratio of 15 was suggested as the optimal condition for the operation of marine aquaponics in which whiteleg shrimp and the three halophytes are target crops.
... A recent study indicated that weight gains and specific growth rates were increased in juvenile Pacific white shrimp receiving dietary supplementation with glycine (Xie et al. 2014). Many factors, such as feeding regime, stocking density, water quality, and other rearing conditions, may affect the requirements of aquatic organisms for dietary AAs (Façanha et al. 2016;Zhang et al. 2018). ...
Chapter
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Crustaceans (e.g., shrimp and crabs) are a good source of protein-rich foods for human consumption. They are the second largest aquaculture species worldwide. Understanding the digestion of dietary protein, as well as the absorption, metabolism and functions of amino acids (AAs) and small peptides is essential to produce cost-effective and sustainable aquafeeds. Hepatopancreas (the midgut gland) is the main site for the digestion of dietary protein as well as the absorption of small peptides and AAs into the hemolymph. Besides serving as the building blocks of protein, AAs (particularly aspartate, glutamate, glutamine and alanine) are the primary metabolic fuels for the gut and extra-hepatopancreas tissues (e.g., kidneys and skeletal muscle) of crustaceans. In addition, AAs are precursors for the syntheses of glucose, lipids, H2S, and low-molecular-weight molecules (e.g., nitric oxide, glutathione, polyamines, histamine, and hormones) with enormous biological importance, such as physical barrier, immunological and antioxidant defenses. Therefore, both nutritionally essential and nonessential AAs are needed in diets to improve the growth, development, molt rate, survival, and reproduction of crustaceans. There are technical difficulties and challenges in the use of crystalline AAs for research and practical production due to the loss of free AAs during feed processing, the leaching of in-feed free AAs to the surrounding water environment, and asynchronous absorption with peptide-bounded AAs. At present, much knowledge about AA metabolism and functions in crustaceans is based on studies of mammals and fish species. Basic research in this area is necessary to lay a solid foundation for improving the balances and bioavailability of AAs in the diets for optimum growth, health and wellbeing of crustaceans, while preventing and treating their metabolic diseases. This review highlights recent advances in AA nutrition and metabolism in aquatic crustacean species at their different life stages. The new knowledge is expected to guide the development of the next generation of their improved diets.
... A recent study indicated that weight gains and specific growth rates were increased in juvenile Pacific white shrimp receiving dietary supplementation with glycine (Xie et al. 2014). Many factors, such as feeding regime, stocking density, water quality, and other rearing conditions, may affect the requirements of aquatic organisms for dietary AAs (Façanha et al. 2016;Zhang et al. 2018). ...
Chapter
Aquaculture is increasingly important for providing humans with high-quality animal protein to improve growth, development and health. Farm-raised fish and shellfish now exceed captured fisheries for foods. More than 70% of the production cost is dependent on the supply of compound feeds. A public debate or concern over aquaculture is its environmental sustainability as many fish species have high requirements for dietary protein and fishmeal. Protein or amino acids (AAs), which are the major component of tissue growth, are generally the most expensive nutrients in animal production and, therefore, are crucial for aquatic feed development. There is compelling evidence that an adequate supply of both traditionally classified nutritionally essential amino acids (EAAs) and non-essential amino acids (NEAAs) in diets improve the growth, development and production performance of aquatic animals (e.g., larval metamorphosis). The processes for the utilization of dietary AAs or protein utilization by animals include digestion, absorption and metabolism. The digestibility and bioavailability of AAs should be carefully evaluated because feed production processes and AA degradation in the gut affect the amounts of dietary AAs that enter the blood circulation. Absorbed AAs are utilized for the syntheses of protein, peptides, AAs, and other metabolites (including nucleotides); biological oxidation and ATP production; gluconeogenesis and lipogenesis; and the regulation of acid-base balance, anti-oxidative reactions, and immune responses. Fish producers usually focus on the content or digestibility of dietary crude protein without considering the supply of AAs in the diet. In experiments involving dietary supplementation with AAs, inappropriate AAs (e.g., glycine and glutamate) are often used as the isonitrogenous control. At present, limited knowledge is available about either the cell- and tissue-specific metabolism of AAs or the effects of feed processing methods on the digestion and utilization of AAs in different fish species. These issues should be addressed to develop environment-friendly aquafeeds and reduce feed costs to sustain the global aquaculture.
... growth of shrimp is often not synchronized; some grow fast, whereas some grow slow, which affects the economic benefits of farmers. It has been reported that the growth performance of aquatic animals is related to genetics (Tan et al., 2019), environmental factors (Duy et al., 2012), disease (Sellars et al., 2019), stocking density (Façanha, Oliveira-Neto, Figueiredo-Silva, & Nunes, 2016) and food (Sookying, Silva, Davis, & Hanson, 2011). Till now, the main mechanism that affects the asynchronous growth of shrimp is still unclear. ...
Article
Penaeus monodon provides a high‐quality protein source for humanity, and pond cultured shrimp often presents asynchronous growth. Microbial communities are important for the digestion and immunity of shrimp. Therefore, in this study, we investigated the bacterial characteristics of the intestine and rearing water of asynchronously growing P. monodon that were cultured in outdoor and indoor pond respectively. The results showed that the bacterial community of the rearing water was more complex than that of the intestine; the fast‐growing shrimp in the indoor pond had higher intestinal bacterial diversity. Besides, the dominant bacterial composition of the water was more complex than that of the intestinal. Specifically, the abundance of Proteobacteria in the intestine was consistent with the growth performance of shrimp in the outdoor pond, which was exactly the opposite in the indoor pond. At the genus level, two cyanobacteria, Limnothrix and Cyanobium PCC‐6307, were dominant in the indoor and outdoor water respectively. In the outdoor pond, Bacillus was dominant in the slow‐growing shrimp intestines, while Vibrio was dominant in the fast‐growing shrimp. The intestinal microbes of the fast‐growing shrimp had higher proteasome metabolic capacity. These results can provide new insights into microbiome characteristics involved in the asynchronous growth of shrimp.
... The values were similar to the reported by Bauer et al. (2012), who found that methionine and threonine decreased as the replacement of FM increa-sed. Methionine is considered an essential amino acid for shrimp, recommended at levels from 1.9 to 2.9 to cover the requirements of P. vannamei Façanha et al., 2016). In this trial, the deficiency in methionine coincided with a low survival of shrimp. ...
Article
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The present study was focused on assessing the effect of diets formulated with different sources and levels of protein on the production response of white leg shrimp Penaeus vannamei farmed at low salinity (3 g L-1). The protein sources were: soy meal (SM) and fish meal (FM), included at three levels: low (22-25%), medium (32-35%), and high (41-45%). A bioassay of 49 days was done in experimental tanks of 100 L (three tanks per treatment). Juvenile P. vannamei having a mean weight of 1.41 ± 0.30 g were stocked at a density of 100 ind m-3. Shrimp fed diets formulated with FM recorded significantly higher weight gain, specific growth rate (SGR), and protein assimilation efficiency rate (PER). Additionally, it showed a higher concentration of essential amino acids like methionine and threonine, and higher ash, calcium, iodine, phosphorous, and sodium content, which could favor the growth and survival of shrimp. Regression analysis showed that the optimum protein levels for diets formulated with SM and FM were 34.8 and 29.3%, respectively. These findings may help shrimp farmers to implement better feeding strategies for P. vannamei farmed at low salinity and on the use of alternative ingredients to substitute fish meal in the formulated feed.
... Daily, before each meal, all uneaten feed was collected and stocked under -20°C. At the end of the experimental period, feed remains were oven-dried and weighed to calculate AFI (Façanha et al., 2016;Nunes et al., 2006b). ...
Article
Based on the ''nutritional programming'' concept, we evaluated the long-term effects of an early four-day caloric restriction (40% reduction in feed allowance compared to a normal feeding level) at the protozoea stage in whiteleg shrimp. We analyzed long-term programming of shrimp by studying metabolism at the molecular level, through RT-qPCR of key biomarkers (involved in intermediary metabolism and digestion). The mRNA levels (extracted from the whole body) were analyzed after the stimulus and after the rearing period, at 20 and 35 days, respectively. At the end of the experimental period, shrimp growth performance was evaluated. There was no difference between normal feed allowance (CTL) and feed-restricted shrimp (RES) for performance parameters (survival, final body weight and the number of post-larvae g −1 or PL g −1). The stimulus directly affected the mRNA levels for only two genes, i.e., preamylase and lvglut 2 which were expressed at higher levels in feed-restricted shrimp. In the long-term, higher levels of mRNAs for enzymes coding for glycolysis and ATP synthesis were also detected. This suggests a possible long-term modification of the metabolism that is linked to the stimulus at the protozoea stage. Overall, further studies are needed to improve nutritional programming in shrimp.
... Muscle of L. santolla juveniles has high amounts of methionine, arginine, tryptophan (9%, 11.4% and 12.6% respectively) than the muscle of pre-adults and adults. In industrially manufactured shrimp feeds, methionine is considered the most limiting essential amino acid [93]. Methionine and arginine are essential amino acids that are critical for optimal growth and survival of crustaceans [94][95][96][97]. ...
Article
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The southern king crab (SKC) Lithodes santolla is an important commercial species in southern South America. Fishing pressure has caused the deterioration of its stocks. Currently, culture techniques are being developed for producing SKC juveniles to enhance the natural population and to recover the fishing stock. Therefore, it is necessary to know about physiology, energetic and nutritional requirements for SKC maintenance in hatchery. Thus, this study aims to evaluate the biochemical and physiological changes in the midgut gland, muscle and hemolymph of juveniles, pre-adults and adults of wild SKC. The energetic reserves, digestive enzymes activity, amino acid profile and energy were quantified in twelve juveniles, ten pre-adult, and ten adult crabs. Juveniles showed high glycogen and low lipids in the midgut gland, and low proteins and low lactate in muscle. In the hemolymph, juveniles had high lipids. Pre-adults had high glycogen and lipids in the midgut gland, and both high protein and lactate in muscle. In the hemolymph, pre-adults had high lipids. Adults had low glycogen and high lipids in midgut gland, and both high proteins and high lactate in muscle. In hemolymph, adults had high glucose and lactate. Juveniles and pre-adults had high proteinase activity, whereas adults had high lipase activity. Major essential amino acids of SKC were arginine, methionine, and tryptophan, and the non-essential amino acids were glycine, aspartic acid and glutamic acid. On another hand, SKC had similar energy in the midgut gland and muscle, regardless of the ontogenetic stage. Moreover, we demonstrated that the biochemical energy calculation underestimates the actual measured values by a calorimeter. Thus, our results help to understand the physiological changes, energetic and nutritional requirements of L. santolla, and this study is a baseline for research on diet formulation for maintaining this species under culture conditions.
... Shrimp were reared in 50 1-m 3 outdoor tanks with 1.14-m of inner diameter on the bottom, 0.74 m height and a bottom area of 1.02 m 2 (Façanha et al. 2016(Façanha et al. , 2018Nunes, Sá, and Sabry-Neto 2011). The study was carried out during the rainy season when high evaporation rates and moderate rainfall is recorded on the site. ...
Article
This work evaluated if dietary supplementation of astaxanthin krill oil with or without soybean oil to a grower shrimp feed enhances the growth performance of L. vannamei farmed under salinity stress. Shrimp of 1.08 ± 0.11 g body weight (BW) were reared for 74 days under 135 animals/m 2 in 50 1-m 3 outdoor tanks. Half of the tanks were operated enclosed by a milky-colored sheet and the remaining ones were fully exposed to sunlight and rain. Shrimp were fed a 38% crude protein feed top-coated with astaxanthin krill oil (K) and/or soybean oil (S) at ratios of 0K-3S, 1K-2S, 2K-1S, and 3K-0S% of the diet, as fed basis, respectively. In air-exposed tanks, mean salinity reached 31 ± 6 g/L compared to 36 ± 4 g/L in enclosed tanks. Shrimp survival was similarly high in both rearing systems (90.6 ± 3.8 and 89.2 ± 5.3% in air-exposed and enclosed tanks, respectively) and was unaffected by oil supplementation (P > .05). Shrimp raised in the air-exposed tanks achieved a significantly higher final BW, weekly growth, gained yield, apparent feed intake (AFI) and a lower FCR (feed conversion ratio) compared to animals in the enclosed tanks. As a result of top-coating feed for the air-exposed tanks with the 1K-2S oil mix, the highest shrimp final BW (14.03 ± 0.52 g) and yield (1,515 ± 40 g/m 2) could be achieved when compared to the enclosed rearing system and all the other diets. Under longer exposure periods to hypersalinity in enclosed tanks, a minimum of 2K-1S was required to maximize BW (10.80 ± 0.63 g) when compared to the other enclosed diet groups.
... It has been reported a value of 2.05% and 0.72% under certain breeding conditions of shrimp, respectively. (Xie et al.,2012;Façanha et al., 2016). ...
Article
Microbial fermentation is an efficient, economical and eco-friendly approach to overcome the limitations in soybean meal replacement of fish meal in aquaculture. However, little research focused on the development of shrimp-derived strains for fermentation of SBM. In this study, Bacillus sanfensis (SQVG18) and Bacillus stratosphericus (SQVG22) were screened from shrimp intestine for fermentation according to the activities of protease, cellulase and phytase. The optimized fermentation conditions of SQVG18 and SQVG22 were as follow: fermentation temperature (40°C vs 35°C), fermentation time (48h both), inoculation amount [4% both (v/m)], solid-liquid ratio [1:1.2 vs 1:1 (g/ml)]. After 48h fermentation, SQVG18 and SQVG22 increased crude protein content by 6.93% and 5.95%, respectively; degraded most of macromolecular proteins to micromolecular proteins (< 20 kDa); improved amino acids profiles, like lysine and methionine in particular; significantly decreased the anti-nutritional factors such as trypsin inhibitor, glycinin and β-conglycinin (P < 0.05). In addition, both strains were observed no hemolytic activity, less antibiotic resistance genes and definite inhibition to common shrimp pathogens of Vibrio alginolyticus sp. and Vibrio parahaemolyticus sp. These results indicated that both strains could improve nutrition values of soybean meal effectively and have potential applications in shrimp culture.
... Therefore, in agreement with previous studies, there is no clear indication that enhanced growth could have been driven by an increased dietary supply of these nutrients. Dietary EAA composition in our study, including Met + Cys, likely met minimum levels to optimize the growth of whiteleg shrimp under green-water rearing systems (Façanha, Oliveira-Neto, Figueiredo-Silva, & Nunes, 2016; leading to its lower performance. Based on this, we support the premise that growth enhancement in low fishmeal diets is driven by ingredient freshness, a collective and stimulatory effect on feed intake, and a higher supply of key nutrients, possibly LC-PUFAs. ...
Article
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... The shrimp used here were reared at LANOA (Aquatic Organisms Nutrition Laboratory, Federal University of Ceará, Eusébio) on an outdoor green water (autotrophic) rearing system (described in Nunes et al. 2011;Façanha et al. 2016). For the experiment, we used 900 shrimps from a commercial specific pathogen resistant (SPR) strain. ...
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Equilibrium between the gastrointestinal bacterial population and the environment is a critical factor for the health of captive aquatic animals. The bacterial enzymes are fundamental for proper nutrition and pathogen resistance in shrimp. Therefore, enzymatic profiles reveal essential characteristics for the selection of probiotic strains that can improve animal development. In this work, we analysed shrimp from a green water system where infectious myonecrosis virus (IMNV) was present. We isolated transient and intestine resident bacterial populations, characterising eight functional groups through different culture media. To identify each isolated bacteria, we used sequences from regions V6–V8 of the 16S rRNA. To determine viral load of shrimp samples, we used real-time PCR. The number of colony forming units (CFU) was similar between IMNV-infected and IMNV-uninfected shrimps. The growth of transient bacteria was higher than the growth of resident. In general, lipolytic bacteria presented higher frequency and genus diversity than the other functional groups. All groups showed higher frequency among transitory bacteria, except the amylolytic functional group, which was more frequent among the resident. We found two major orders of cultivable bacteria, Vibrionales and Bacillales. The genus Vibrio was predominant among the Vibrionales, while Staphylococcus and Bacillus were the most frequent among the Bacillales. Recorded Vibrionales and Bacillales included pathogenic and beneficial species of high importance for aquaculture. The results presented here will serve as a basis for improving the nutritional and health conditions of Litopenaeus vannamei in green water farming systems.
... The rearing system adopted in this study has been described by Nunes et al. (2011) and Façanha et al. (2016Façanha et al. ( , 2018. Briefly, the system was composed of independent outdoor tanks, round, blue in color, with 1.14 m of inner diameter on the bottom, 0.74-m height, and a total bottom area of 1.02 m 2 . ...
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In the coming years, supplementation of crystalline amino acids (CAAs) will become a standard practice driven by the trend towards low-fish meal diets. We have evaluated the effect of feeding juvenile L. vannamei several times a day versus two (2×) and four (4×) times using a low-fish meal diet supplemented with CAAs. A total of 1632 shrimp of 1.06 ± 0.16 g were stocked in 16 outdoor tanks of 1 m³ under 100 shrimp/m². Shrimp were either fed manually, 2× or 4× daily, using one feeding tray per tank, or fed with an automatic feeder to deliver multiple (10) meals during the day or during the day and night (D&N) at programmed times. A diet containing 3% fish meal was prepared to contain supplemental levels of CAAs. After 11 weeks of rearing, survival, growth performance, and feed efficiency of shrimp were significantly affected by feeding frequency and time of feeding. Feeding 2× and 4× daily resulted in a lower survival compared to multiple times during the day or D&N. Shrimp body weight was enhanced with an increase in feeding frequency, from 8.74, 10.95, 11.33, and 11.33 g under 2×, 4×, and multiple feedings during the day or during D&N, respectively. FCR was also significantly affected, reducing from a high of 2.46 under 2× to 1.59 under multiple feedings D&N. Our findings indicate that it is more advantageous to feed juvenile L. vannamei multiple times a day when a low-fish meal amino acid-supplemented diet is used.
... Daily, before each meal, all uneaten feed was collected and stocked under -20°C. At the end of the experimental period, feed remains were oven-dried and weighed to calculate AFI (Façanha et al., 2016;Nunes et al., 2006b). ...
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In this study, the concept of metabolic programming has been tested for the first time in whiteleg shrimp (L. vannamei). Shrimp were raised under a 70% feed restriction during the post-larval stage over three days and compared to a control group. After 46 days, shrimp were challenged with 3 diets showing different nitrogen free-extract: crude protein ratios (1.5, 1.0 and 0.7) for 70 days. In order to test the existence of metabolic programming, we analyzed shrimp growth performance as well as mRNA levels of different metabolic and digestive actors after the stimulus, and also before and after the challenge. No direct effects of the stimulus were observed for several digestive and metabolic actors, except for the trypsin mRNA (lower in the feed-restricted group, probably linked to a decrease in dietary protein intake). As expected, significant effects associated with the diet challenge were detected for shrimp performance, i.e., growth was lower in shrimp fed with reduced levels of dietary proteins. More interestingly, some effects linked to the nutritional history were also detected showing an improved growth performance for shrimp previously restricted at the post-larvae stage. After the dietary challenge, significantly lower mRNA levels for hepatopancreatic genes involved in digestion (lipase, preamylase and trypsin), amino acid metabolism (gs), energy metabolism (cox VI b) and glucose metabolism (lvglut 1, lvglut 2 and pk) were found in restricted shrimp. The link between an enhanced growth performance and these molecular markers in early feed restricted shrimp requires further studies. Overall, our study has demonstrated for the first time that shrimp can be programmed by an early nutritional stimulus. This will allow the development of new feeding strategies in shrimp for sustainable aquaculture
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Shrimp maturation and seed production are vital to the aquaculture industry and crucial for meeting rising global demand. This chapter reviews recent advancements, challenges, and trends in shrimp maturation and seed production, with a focus on India. Since Fujinaga’s 1930s work in Japan on Kuruma shrimp larval rearing with diatom Skeletonema, substantial progress has been made globally. Improved understanding of reproductive physiology, particularly in penaeids, has led to advances in maturation techniques. Controlled conditions like temperature, photoperiod, and nutrition are essential for inducing maturation and spawning. Hormonal manipulation and selective breeding have boosted maturation efficiency and yields. Advances in larval rearing, specialized feeds, water quality, and biosecurity have enhanced early-stage survival rates. However, challenges such as disease outbreaks, especially viral, threaten production systems. Disease prevention strategies, including genetic resistance and biosecurity, are essential for resilience. Continued research is vital for sustainable growth in this evolving field, balancing scientific advancements with industry needs.
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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.
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Mexico ranks second in shrimp (Litopenaeus vannamei) production of in Latin America with significant annual growth, however, during 2011 shrimp production fell by almost 50 % due to the presence of the white spot syndrome virus (WSSV). In this context, a life cycle analysis (LCA) and data envelopment analysis (DEA) were performed on 76 commercial farms severely affected by the presence of WSSV in northwestern Mexico. The application of this combined methodology allowed a detailed quantification of different environmental impact categories. During the presence of WSSV, there was a negative effect on the feed conversion ratio (FCR) (>40 %), higher consumption of seawater (38 %), and energy (38 %). Consequently, operational outputs related to the discharge of nitrogen and phosphorus increased by 60 and 57 %, respectively. Similarly, CO2 emissions, increased by 38 % relative to a typical year of production. Overall, the main critical points in the impact categories analyzed are related to food (98 %), use of diesel (23 %), and rearing (24 %), dominating pollutants emissions in all categories. Consequently, an improvement scenario was evaluated related to innovation in the formulation of foods supplied with immunostimulants, which confer protection against pathogenic microorganisms. This scenario lead to a reduction environmental impact of about 82 %. The results of this analysis will be a useful resource in the design of mitigation strategies with innovation processes that allow maintaining yields for shrimp producers in this region and at the same time reduce the environmental impacts generated.
Chapter
Methionine and cysteine are essential proteinaceous amino acids (AA) with Met as one of the most versatile and important AAs. Met is central in the one-carbon metabolism and appears to be toxic in elevated doses, whereby the underlying modes of action remain to be identified in aquatic animals. Moreover, it plays a role in the synthesis of creatine, polyamines, and choline. In many feedstuffs, Met is one of the most limiting AAs, particularly in plant-based aquafeeds. Met has a pronounced beneficial influence on the innate immune response. The demand for appropriate immune response appears to be elevated in animals on plant-based diets. A few attempts show that, at least in several fishes, Met can successfully be replaced with Met hydroxyl analog. Due to mutual sparing effects of total sulfur AAs, growth requirements should be expressed in terms of total SAA rather than Met or Cys alone – a classical request in aquatic animal nutrition. Concluding, this chapter points out gaps in the understanding of controlling by sulfur AAs. Although Met is one major methyl donor, epigenetics in the metabolism of and controlling by sulfur AAs is sparsely studied. The same applies to the microbiota-host axis of interactions.
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An eight‐week growth trial and a four‐week digestibility trial was undertaken to assess the impact of DL‐methionine and phytase supplementation on growth performances, apparent digestibility coefficients (ADC), phosphorus retention and digestive enzyme activities of Penaeus vannamei. Five treatment groups in three replicates fed with a control diet (fishmeal 200 g/kg), and four low fishmeal (50 g/kg) diets with soy protein concentrate‐soybean meal protein viz., SPC1 (without supplementation), SPC 2 (DL‐methionine), SPC 3 (Phytase) and SPC4 (DL‐methionine and phytase). SPC 2 had significantly improved (p < .05) the weight gain (5.79 ± 0.12), FCR (1.53 ± 0.06) and SGR (3.21 ± 0.06) than other low fishmeal diets, but not significantly different to that of SPC 4 and control. SPC 2 also showed significantly higher protease activity. P retention was significantly higher in SPC 2 than SPC 1, SPC 3 and control, however, not significantly different from SPC 4. Faecal phosphorus load was significantly reduced in SPC 2 than SPC 1 and control. Protein digestibility was significantly higher in SPC 2 and SPC 4, whilst phosphorus digestibility was significantly higher in SPC 4. Thus, it is concluded that the supplementation of DL‐methionine is essential for the overall better performances of P. vannamei in low fishmeal diets and phytase for improving phosphorus digestibility.
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This trial was conducted to determine the optimal dietary methionine requirement for juvenile sea cucumber Apostichopus japonicus selenka. Six isonitrogenous and isoenergetic experimental diets were formulated with graded methionine levels (0.18%, 0.37%, 0.57%, 0.78%, 0.96%, 1.10% dry matter). Each diet was assigned randomly to triplicate groups with 30 sea cucumbers juveniles with initial body weight 12.14 g in a recirculated aquaculture system for 56 days. Survival rate was not affected by dietary methionine. With the increase of dietary methionine levels, both weight gain and specific growth rate were significantly increased initially and then decreased afterwards. Both crude protein and crude lipid contents of body wall were evaluated firstly and dropped afterwards. meanwhile, contents of methionine, cystine, aspartic acid and total amino acids of body wall were all increased. Both total antioxidant capacity and total superoxide dismutase activities of intestine were increased, while malondialdehyde contents were decreased with the increase of dietary methionine. All of activities of protease and lipase were increased initially and then decreased afterwards; however, there was no significantly effect on amylase. In conclusion, analysis by a linear regression equation of WG or methionine contents in body wall indicated that the optimum requirement of methionine for juvenile sea cucumber (initial body weight 12.14 g) was 0.58%–0.72% diet (2.77%–3.42% diet protein).
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The present study investigated the effects of dietary DL-methionyl-DL-methionine (Met-Met) on growth performance, intestinal immune function and the underlying signalling molecules in juvenile grass carp (Ctenopharyngodon idella). Fish were fed one DL-methionine (DL-Met) group (2.50 g/kg diet) and six graded levels of Met-Met groups (0, 0.79, 1.44, 1.84, 2.22 and 2.85 g/kg diet) for 10 weeks, and then challenged with Aeromonas hydrophila for 14 days. Results indicated that the optimal Met-Met supplementation: (1) increased fish growth performance, intestinal lysozyme (LZ) and acid phosphatase (ACP) activities, complement (C3 and C4) and immunoglobulin M (IgM) contents, up-regulated hepcidin, liver expressed antimicrobial peptide 2A (LEAP-2A), LEAP-2B, β-defensin-1 and Mucin2 mRNA levels; (2) down-regulated tumour necrosis factor α (TNF-α), interferon γ2 (IFN-γ2), interleukin 1β (IL-1β), IL-8 [only in the distal intestine (DI)], IL-12p35, IL-12p40 and IL-15 (not IL-17D) mRNA levels partially related to the down-regulation of IκB kinase β (IKKβ) and IKKγ (rather than IKKα), nuclear factor kappa B (NF-κB) p65 and c-Rel (rather than NF-κB p52) mRNA levels and the up-regulation of inhibitor of κBα (IκBα) mRNA levels; (3) up-regulated IL-4/13A, IL-4/13B, IL-6, IL-10, IL-11 and transforming growth factor (TGF)-β1 (not TGF-β2) mRNA levels partially associated with the target of rapamycin (TOR) signalling pathway [TOR/ribosomal protein S6 kinases 1 (S6K1), eIF4E-binding proteins (4E-BP)] in three intestinal segments of juvenile grass carp. These results suggest that Met-Met supplementation improves growth and intestinal immune function in fish. Furthermore, according to a positive effect, the optimal Met-Met supplementation was superior to the optimal DL-Met supplementation at improving the growth performance and enhancing the intestinal immune function in fish. Finally, based on percent weight gain (PWG), protection against enteritis morbidity and immune index (LZ activity), the optimal Met-Met supplementation for juvenile grass carp was estimated as 1.61, 1.64 and 1.68 g/kg diet, respectively, as the basal diet contains 8.03 g/kg total sulfur amino acids (TSAA) (4.26 g methionine/kg and 3.77 g cysteine/kg).
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In order to examine the effects of stocking density on growth, food intake, energy budget, and expression levels of related genes of the abalone Haliotis discus hannai Ino, specimens (mean ± standard error shell length: 36.25 ± 1.97 mm, weight: 6.88 ± 0.71 g) were cultured at four different stocking densities (600, 900, 1200, and 1500 ind/m²). Four replicates were set for each density, and the experimental period was 60 days. At the end of the experiment, the survival rate, shell length, and weight specific growth rate of abalones in the 600 and 900 ind/m² groups were significantly higher than in the 1200 and 1500 ind/m² groups (P < 0.05). The food conversion rate of abalones in the 900 ind/m² group significantly increased compared with the other groups (P < 0.05). The activity of hexokinase in the 1200 and 1500 ind/m² groups was significantly higher than that in 600 and 900 ind/m² groups (P < 0.05). The activity of pyruvate kinase in the 1500 ind/m² group showed no significant difference compared with the 900 and 1200 ind/m² groups (P > 0.05), but was significantly higher than that in the 600 ind/m² group (P < 0.05). In the 1200 and 1500 ind/m² groups, lactic dehydrogenase activity at Day 60 increased significantly compared with Day 30 (P < 0.05). In the 900 ind/m² group, the energy accumulated for the growth was significantly higher than that in the 1200, and 1500 ind/m² groups (P < 0.05), but there was no significant difference compared with the 600 ind/m² group (P > 0.05). As the stocking density increased, expression levels of Mn-superoxide dismutase, catalase, glutathione-s-transferase, thioredoxin peroxidase, and heat shock protein 70 in the 1500 ind/m² group at the end of the experiment were significantly higher than in the other groups (P < 0.05). At Day 30, the expression level of heat shock protein 90 in the 1200 ind/m² group showed no significant difference compared with the 1500 ind/m² group (P > 0.05), but it was significantly lower than that in the 1500 ind/m² group at the end of the experiment (P > 0.05). In the 1200 and 1500 ind/m² groups, the food availability was lower, levels of anaerobic metabolism increased, and more energy was required to resist oxidative damage; therefore, no energy was accumulated for growth. When the stocking density was 900 ind/m², the survival rate of abalones was the highest with fast growth, the density factor didn't cause oxidative stress to the organism, and more food-derived energy were accumulated and used for the growth of abalones. Considering aquaculture production output and business profitability, it would be more appropriate to control the stocking density at 900 ind/m² for abalones with a shell length of 3–4 cm.
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Feeding frequency and density are two of the most important factors that directly affect the growth and physiology of sea cucumber Apostichopus japonicus. In the present study, a 60-day experiment was conducted to evaluate the effects of feeding frequency (1 time, 2 times and 3 times per day) and stocking density (D10, D20, D40 and D60) on growth performance, feed utilization, endocrine response and energy budget of sea cucumber. The results revealed that there was no significant interaction between feeding frequency and stocking density on final weight and specific growth rate (SGR). The maximum SGR occurred at treatment of stocking density D10 with feeding thrice per day. Stepwise multiple regression analysis showed that SGRW and SGRE increased with increasing feeding frequency, and decreased with the increase of stocking density. Density had significant influence on coefficient of variation (CV) for the sea cucumber body weight. For D10 and D20, no significant difference in CV was found between different feeding frequencies. Feed intake, energy intake and feces production rate were significantly affected by feeding frequency, stocking density and their interaction. Density also had significant influence on food conversion efficiency and protein efficiency ratio. Apparent digestibility coefficients of crude protein and crude lipid exhibited remarkable descending trends as stocking density increased. The energy for growth decreased and energy required for metabolism increased with the increase of stocking density, suggesting that crowding stress modified their energy allocation by inhibiting the accumulation of growth energy and accelerating energy consumption of sea cucumber. Cortisol level in coelomic fluid of sea cucumber significantly increased with the increase of stocking density, which could generate energy to satisfy the increasing demand of stress-related energy. Lactate level significantly elevated, and glucose level in coelomic fluid and glycogen in muscle showed remarkable descending trends from D10 to D60, implying long-term energy consumption under high stocking density. Feeding frequency had significant influence on glucose, glycogen and cortisol levels. To some extent, increasing feeding frequency could effectively reduce coefficient of variation of sea cucumber, especially under high stocking density. Statement of relevance • In the present study, a 60-day experiment was conducted to evaluate the effects of feeding frequency (1 time, 2 times and 3 times per day) and stocking density (D10, D20, D40 and D60) on growth performance, feed utilization, endocrine response and energy budget of sea cucumber. • Increasing feeding frequency could effectively reduce coefficient of variation of sea cucumber. • The present study provided valuable information for the intensive culture of A. japonicus.
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Three feeding trials were conducted to determine the dietary methionine requirements for Litopenaeus vannamei of three different sizes, small (0.55 +/- 0.01g), medium (4.18 +/- 0.05g), and large (9.77 +/- 0.08g). Seven diets were formulated with seven different levels of methionine (0, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, or 0.6%). The greatest weight gain (WG) and specific growth rate (SGR) of small and large shrimp were observed when dietary methionine levels were 0.8%, and 0.71%, respectively (P<0.05). The highest survival rate of small and large shrimp was observed when dietary methionine levels were 0.97%, and 1.07%, respectively (P<0.05). For small and medium shrimp, the optimal dietary methionine level for maximum weight gain estimated by quadratic regression analysis was 0.91% and 0.67% of dry diet, respectively. For large shrimp, the optimal dietary methionine requirement estimated by broken-line model based on weight gain was 0.66% of dry diet.
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This study was designed to determine the isoleucine requirement of juvenile Pacific white shrimp Litopenaeus vannamei (Boone) in low-salinity water (0.50–0.70 g L−1). Six diets were formulated to contain 410 g kg−1 crude protein with fish meal, peanut meal and pre-coated crystalline amino acids with different concentration of l-isoleucine (9.35, 11.85, 14.35, 16.85, 19.35, and 21.85 g kg−1 dry diet, defined as diet I1, diet I2, diet I3, diet I4, diet I5 and diet I6, respectively.). Each diet was randomly assigned to triplicate treatments of 30 shrimps (0.43 ± 0.005 g), and the feed trial lasted for 8 weeks. The results indicated that the weight gain significantly increased with increasing isoleucine concentration up to 14.35 g kg−1 (diet I3), whereas it was reduced in the treatments exceeding 16.85 g kg−1 isoleucine (diet I4) significantly (P < 0.05). Moreover, the highest body protein deposition and protein efficiency ratio, and the lowest feed conversion ratio, haemolymph aspartate aminotransferase and alanine aminotransferase activities were also found at treatment I3–I4 (P < 0.05). And the haemolymph urea nitrogen concentration of shrimps-fed diet I6 was particularly higher than those fed with diets I1–I5 (P < 0.05). The results of polynomial regression based on weight gain, feed efficiency and body protein deposition indicated that the optimal dietary isoleucine requirement for L. vannamei reared in low-salinity water was 15.95 g kg−1 isoleucine of dry diet, correspondingly 38.81 g kg−1 of dietary protein.
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This 35-d feeding experiment examined in juvenile shrimp Penaeus monodon (3·3 g initial body weight) the effects of methionine (Met), choline and cystine on protein accretion and the activity of two key enzymes of remethylation (betaine-homocysteine methyltransferase; BHMT) and trans-sulfuration (cystathionine β-synthase; CBS). The interaction between Met and choline was tested using semi-purified diets either adequate or limiting (30 or 50 %) in total sulphur amino acid (SAA) content with a constant cystine:Met ratio. The diets contained either basal or excess choline (3 v. 7 g/kg feed). Cystine was added to two other 30 and 50 % Met-limiting diets to adjust the SAA supply to that of the control diet in order to evaluate the interaction between Met and cystine. As expected, N accretion was significantly lower with the SAA-limiting diets but increased back to control levels by the extra choline or cystine, demonstrating their sparing effect on Met utilisation for protein accretion. We show, for the first time, the activities of BHMT and CBS in shrimp hepatopancreas. Only BHMT responded to the SAA deficiencies, whereas the extra choline and cystine did not stimulate remethylation or down-regulate trans-sulfuration. Our data also suggest the capacity of P. monodon to synthesise taurine, being significantly affected by the cystine level in the 30 % SAA-limiting diets. Further research is warranted to better understand the metabolic regulation of taurine synthesis in shrimp and of the observed Met-sparing effects.
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A study was conducted to evaluate variations of digestive enzyme activities in Litopenaeus vannamei (Boone) reared in commercial ponds under semi-intensive conditions. Shrimp were collected at each body weight increase of 2 g. As the shrimp grew (2-12 g), significant increases in the activities of lipase and chymotrypsin were observed. The total protease activity decreased from 6 g onwards. Trypsin activity showed a peak at 6 g and amylase activity increased two-fold after 2 g. Additionally, the stomach contents were analysed microscopically for shrimp between 2 and 10 g. Plant matter contributed above 30% of the total stomach content in 6-, 8- and 10-g shrimp. Detritus represented 58% and 62% of the total stomach content in 2- and 4-g shrimp, respectively, decreasing to 33-43% at greater shrimp weights. Artificial feed showed a maximum contribution of 20% in 6-g shrimp. The present results show changes in the enzyme activity after the shrimp reach 6 g in body weight, evidenced by a decrease in total protease and an increase in lipase and amylase activities. The amylase/protease ratio was 2.6 in 2-g shrimp and increased steadily to 9.6 in 12-g shrimp. These findings suggest an adaptation of the enzymatic activity to diets with lower protein content as body weight increases, and may be related to the variation of the different items found in the stomach.
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Although the literature has contributed to identifying various influences on passenger choice of low-cost carriers (LCCs), the evaluation of the relative importance of these factors has not been empirically determined. In their decision about choices of LCCs, passengers may consider more than one factor or criterion. Passenger choice of LCCs can be viewed as a multi-criteria decision-making problem and the various factors involved are interdependent. Analysis network process (ANP) methodology satisfies these requirements by considering inner and outer dependences among multiple criteria. In this study, the goal is to use ANP to evaluate the relative weights and priorities of the factors determining passenger choice of LCCs. Firstly, literature review and expert opinion are conducted to generate 16 sub-criteria along with four criteria (e.g., perceived advantages, perceived external influence, perceived service quality, and perceived corporate value) that affect passenger choice of LCCs. Secondly, ANP is applied to develop an evaluation model that prioritized the relative weights linking the above four criteria with 16 evaluated sub-criteria. The results not only provide an evaluation model to determine the relative importance of the influences of LCCs on passenger choice, but can also help managers focus on the main factors and identify the best policy for promoting passenger acceptance toward LCCs.
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This study evaluated the effects of increasing levels of methionine (Met) supplementation on the success of almost total replacement of fish meal (FM) with soybean meal (SBM) in diets for hybrid tilapia (Oreochromis niloticus × Oreochromis mossambicus). Fish were fed for 70 days a FM-based diet (Diet1-positive control) or SBM-based diets supplemented with graded levels of DL-methionine (Diet2 to Diet7). Contrast in dietary Met, concentration was created by supplementing Diet2-negative control with 1.2 (Diet3), 2.4 (Diet4), 3.6 (Diet5), 4.8 (Diet6) or 6.0 g kg−1 (Diet7) of DL-Met. Specific growth rate (SGR), feed conversion ratio (FCR), and protein gain and retention efficiency (PER) improved significantly with increasing levels of dietary DL-Met supplementation. Moreover, nonlinear regression analysis of the effects of supplementing SBM-based diet with graded levels of DL-Met indicated that a dietary Met + Cys level of 15.7 and 12.5 g kg−1 diet (as fed) was required to reach 95% of maximum weight and protein gain, respectively. Supplementation of SBM-based diet with graded levels of DL-Met proved an effective strategy in reducing FM content in practical diets for hybrid tilapia. Data also indicate that adjustment of dietary formulas according to currently recommended Met or Met + Cys dietary concentrations is probably limiting maximum growth potential of hybrid tilapia.
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An 8-week feeding trial was conducted to evaluate the optimum dietary glycine level in low fishmeal diet for juvenile Pacific white shrimp, Litopenaeus vannamei. Six practical diets (44.4% protein, 8.8% lipid) were formulated to contain graded levels (2.26, 2.33, 2.44, 2.58, 2.67 and 2.74%) of l-glycine. Each diet was randomly assigned to triplicate groups of 30 shrimps (approximately 0.61 g) and the shrimps were fed 4 times a day to apparent satiation. The results indicated that the weight gain and specific growth rate were significantly increased with the supplementation of glycine. The highest weight gain and specific growth rate were observed at 2.56% dietary glycine, and then decrease with a further increase in dietary glycine. Hepatosomatic index, protein productive value and condition factor were also significantly influenced by the dietary glycine levels and show a similar trend to those of growth performance. There were no significant differences observed in feed efficiency, protein efficiency ratio and survival among all treatments. Mg, Ca and Fe concentrations in whole body were significantly increased with the supplementation of glycine. Non-essential amino acid, essential amino acid and arginine ratio in muscle were significantly affected by the dietary glycine levels. Dietary glycine levels higher than 2.44% significantly increased the survival of shrimps after 2 h and 3 h of acute salinity change, and T-SOD activity and Na+/K+-ATPase activity in hematological and hepatopancreas before and after acute salinity change are also significantly affected by the dietary glycine levels. Analysis by second-order regression of weight gain indicated that the optimal dietary glycine level was 2.54% of the dry diet (5.7% of the dietary protein and 6.66% of the dietary amino acids).
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An 8-week feeding trial was conducted to determine the dietary threonine requirement of juvenile Pacific white shrimp, Litopenaeus vannamei. Six isonitrogenous and isolipidic practical diets (43% crude protein and 7.5% crude lipid) were formulated to contain graded dietary threonine levels ranging from 1.07% to 2.30% (dry weight). In all of the diets, the nitrogen content of the amino acids was kept the same by replacing threonine with a non-essential amino acid mixture. Each diet was randomly assigned to triplicate groups of 40 juvenile shrimp (approximately 0.53 g) that were fed 4 times daily to apparent satiation. The results indicated that significant difference was observed in the weight gain among all treatments. Maximum weight gain was obtained at 1.67% dietary threonine; however, weight gain did not significantly increase with further dietary threonine increases. The survival of the shrimps showed no significant differences among all treatments. Feed efficiency, protein efficiency ratio and protein productive value were also significantly influenced by the dietary threonine levels, and the trends were similar to those of growth performance. There were no significant differences among dry matter, crude protein, crude lipid or ash content in the whole body and muscle composition. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), superoxide dismutase (SOD) and phenoloxidase (PO) activities in hemolymph were significantly affected by dietary threonine levels. Shrimp fed the diet containing 2.30% threonine had higher AST and ALT values than those fed the other diets; however, the highest SOD and PO activities were observed at 2.05% dietary threonine. The optimal dietary threonine requirement, estimated by a broken-line model based on SGR, was 1.51% of the dry diet (corresponding to 3.53% of dietary protein on a dry-weight basis). Considering the threonine leaching loss in seawater within 30 min (duration of feeding each time), the threonine requirement for L. vannamei is 1.18% of dry diet (2.81% of the dietary protein).
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An 8-week feeding trial was conducted to evaluate the dietary arginine requirement of juvenile Pacific white shrimp, Litopenaeus vannamei. Six isonitrogenous and isolipidic practical diets (41% crude protein and 7.5% crude lipid) were formulated to contain graded dietary arginine levels ranging from 1.44 to 2.74% (dry weight) in approximately 0.3% increments. In all of the diets, the nitrogen content of the amino acids was kept the same by replacing arginine with a non-essential amino acid mixture. Each diet was randomly assigned to triplicated groups of 40 juvenile shrimp (approximately 0.50 g) 4 times daily to apparent satiation. The results indicated that the specific growth rate and weight gain were significantly influenced by the dietary arginine levels. Maximal specific growth rate and weight gain occurred at 2.32% dietary arginine; however, specific growth rate and weight gain did not significantly increase with further increases in dietary arginine from 2.51% to 2.74%. Feed efficiency, protein efficiency ratio and protein productive value were also significantly affected by the dietary arginine levels, and the trends were similar to those of growth performance. No mortality was observed among all treatments. There were no significant differences among crude protein, crude lipid and ash content in the whole body and muscle composition. The total protein in hemolymph was significantly affected by dietary arginine levels, however, there were no significant differences in urea nitrogen, triglycerides and cholesterol in the hemolymph among all treatments. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), superoxide dismutase (SOD), arginase and nitric oxide synthase (NO) activities in the hemolymph were significantly affected by dietary arginine levels. The optimal dietary arginine requirement estimated by two slope broken-line model based on SGR was 2.32% of the dry diet (corresponding to 5.66% of dietary protein on a dry weight basis). Considering the arginine leaching loss in seawater within 30 min (duration of feeding each time), the arginine requirement for L. vannamei is 1.96% of dry diet (4.77% of the dietary protein).
Article
An 8-week feeding trial was conducted to estimate the dietary lysine requirement of juvenile Pacific white shrimp, Litopenaeus vannamei. Six isonitrogenous and isolipidic practical diets (40% CP and 7.5% lipid) containing graded dietary lysine levels ranged from 1.44 to 2.49% (dry weight) at about 0.3% increments were formulated. Equal amino acid nitrogen was maintained by replacing lysine with nonessential amino acid mixture. Triplicate groups of 40 juvenile shrimps (about 0.52 g initial weight) were fed one of the diets four times daily to apparent satiation. No significant differences were observed in survival rates of shrimps (97.50–100%, P > 0.05), but specific growth rate (SGR), weight gain (WG), feed efficiency, protein efficiency ratio and protein deposition ratio were significantly affected by different dietary lysine levels (P < 0.05). There were no significant differences in whole body and muscle composition (crude lipid, crude protein and ash), except for the crude protein content of whole body. Urea nitrogen, total protein and the activity of SOD in hemolymph showed no significant differences (P > 0.05). Triglyceride, Aspartate aminotransferase (AST) and Alanine aminotransferase (ALT) in hemolymph were significantly affected by dietary lysine levels (P < 0.05). The optimal dietary lysine requirement estimated by broken-line model based on SGR was 2.05% of dry diet (4.93% dietary protein). Considering the lysine leaching loss in seawater within 30 min (duration of feeding each time), the lysine requirement for L. vannamei is 1.64% of dry diet (3.95% of the dietary protein).
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Microalgae hold a key role in the diet of the world's highest-valued seafood species, Pacific white shrimp Litopenaeus vannamei, but ingestion, digestion, and feeding mechanisms employed for consuming suspended microbes are not well studied. The goal of this work was to determine whether juvenile L. vannamei could consume and digest several microbes of varying sizes and structures in suspended monocultures. Diatoms Thalassiosira weissflogii and Amphiprora sp., eustigmatophyte Nannochloropsis salina, and cyanobacterium Synechococcus bacillarus were chosen based upon their common occurrence in intensive shrimp aquaculture systems.
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In a preliminary experiment, order-of-limitation of lysine, arginine and methionine was determined for wheat gluten fed to juvenile shrimp. Limitation diets were prepared by singular deletion of the crystalline component of one of the above amino acids from a control diet. Shrimp fed deletion diets had significantly less weight gain than those fed the control diet with the order-of-limitation being lysine ≥ methionine ≥ arginine with lysine being significantly more limiting than arginine. In a subsequent experiment, the dietary requirement for lysine was estimated using juvenile Penaeus vannamei and a 21-day experimental period. Shrimp were fed four different types of diets: (1) 35% crude protein, lysine supplementation via covalently lysine-enriched wheat gluten; (2) 35% crude protein, lysine supplementation via l-lysine HCl; (3) 45% crude protein, lysine supplementation via covalently lysine-enriched wheat gluten; and (4) 45% crude protein, lysine supplementation via l-lysine HCl. Diets containing 35% crude protein contained graded levels of lysine ranging from 3.43 to 6.57% of the protein. Lysine in the diets containing 45% crude protein ranged from 3.33 to 6.67% of the dietary protein. Apparent requirement for lysine was estimated by broken-line regression of instantaneous growth coefficient (IGR) against dietary lysine concentration. No significant difference (P < 0.05) in survival was observed among shrimp fed any of the four different types of diets. Irrespective of means of lysine supplementation, the apparent requirement for lysine by shrimp fed diets containing 45% crude protein was 4.67% of the protein. The apparent requirement for lysine by shrimp fed the diet containing 35% crude protein supplemented with wheat gluten and with l-lysine HCl was 4.49 and 5.19% of the protein, respectively.
Article
An 8-week feeding trial was conducted to determine the dietary requirement of postlarval Penaeus monodon for the sulfur-containing amino acid methionine. Shrimp postlarvae (mean weight 21 ± 0.3 mg) were reared in 40-1 fiberglass tanks in a flow-through seawater system. Test diets (37% protein and 360 kcal per 100 g diet) were formulated containing casein-gelatin as protein sources and supplemented with crystalline amino acids to simulate the amino acid pattern in shrimp tissue protein except methionine. The diets contained graded levels of methionine at a range of 0.72–1.12% of the diet or 2.0–3.0% of protein. In diet preparation, the crystalline amino acids were pre-coated with carboxymethylcellulose (CMC) to reduce leaching. Diets were further coated with CMC, cornstarch, and κ-carrageenan to improve water stability and the diet pH was kept at 7.0–7.2 by neutralization with 6N NaOH. Shrimp were fed the diets at 25–30% of their biomass thrice daily. At termination of the feeding experiment, various parameters including growth, survival, and feed conversion efficiency were determined and nutritional deficiency signs noted. The methionine requirement was determined from the relationship between weight gain and dietary methionine level using the broken-line regression method. The requirement of P. monodon postlarvae for methionine was 0.89% of the diet or 2.4% of protein. In a diet containing 0.41% cystine, the total sulfur amino acid requirement (methionine + cystine) would be 1.3% of the diet or 3.5% of protein. This requirement is slightly lower than the methionine level present in shrimp tissue protein.
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Hydrobiology of a modified extensive shrimp (Penaeus monodon) culture pond was monitored. Qualitative and quanti- tative analyses of plankton population revealed higher phytoplankton population during the first six weeks of culture which declined to low level thereafter and remained at that level till the end of the culture period. Zooplankton was represented mainly by rotifers, copepods and mysids. Dense population of rotifers and copepods occurred during the first-month of cul- ture while mysids appeared from the third week of first-month and dominated there after. Composition of zooplankton var- ied depending on the occurrence of Brachionus plicatilis, Keratella spp, Pseudodiaptomus annandalei Paracalanus aculetaus, Oithona brevicornis, Microstella norvegica and Mesopodopsis zeylanica during the culture period. Gut content analyses showed sand grains, zooplankton, pelletized feed and unidentified semi-digested food matter in the proportions of 43%, 16%, 21% and 20% respectively. The percentage of stomach contents varied in different size groups. It is observed that during the early phase of culture natural food contributes considerably to the growth of the shrimp.
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The requirements of juvenile prawn, Marsupenaeus japonicus (Bate), 0.79 g initial body weight, for essential amino acids (EAA) were evaluated based on the daily increase of each EAA in the whole body when the prawn was maintained on a diet with a high nutritive value (a casein-squid protein-based diet). The quantities of each EAA needed daily for growth and maintenance of prawn are conceived to correspond to the daily requirements of this prawn species for EAA. Therefore, these requirement values of respective EAA should be supplied from dietary proteins. To determine these values, protein and amino acids of the whole body of the prawn were quantified before and after feeding experiments, and the quantities of respective EAA needed to meet the requirements were estimated based on the EAA profile of the whole body protein of prawn. As a result, the contents of EAA in dietary proteins (%) needed to meet the requirements of the prawn for EAA were assessed to be: threonine (2.3), methionine (1.3), valine (2.4), isoleucine (2.3), leucine (3.4), phenylalanine (2.6), lysine (3.2), histidine (1.1), arginine (2.9) and tryptophan (0.6), respectively, when the prawn are fed 50% protein diet with 90% protein digestibility at a ration size of 2% (% of body weight).
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Optimising the amino acid supply in tune with the requirements and improving protein utilization for body protein growth with limited impacts on the environment in terms of nutrient loads is a generic imperative in all animal production systems. With the continued high annual growth rate reported for global aquaculture, our commitments should be to make sure that this growth is indeed reflected in provision of protein of high biological value for humans. The limited availability of fish meal has led to some concerted efforts in fish meal replacement, analysing all possible physiological or metabolic consequences. The rising costs of plant feedstuffs make it necessary to strengthen our basic knowledge on amino acid availability and utilization. Regulation of muscle protein accretion has great significance with strong practical implications. In fish, despite low muscle protein synthesis rates, the efficiency of protein deposition appears to be high. Exploratory studies on amino acid flux, inter-organ distribution and particularly of muscle protein synthesis, growth and degradation and the underlying mechanisms as affected by dietary factors are warranted. Research on specific signalling pathways involved in protein synthesis and degradation have been initiated in order to elucidate the reasons for high dietary protein/amino acid supply required and their utilization.
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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.
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1.1. Water turnover rates were measured in Limulus, Penaeus and three species of Uca.2.2. Limulus was the only species studied that lowered its permeability to water when acclimated to lower salinities.3.3. Stress, feeding movements or walking leg autotomy do not affect the water permeability of Uca.4.4. The Q10 of water influx in Limulus and Uca is approximately 2.5.5. All three genera ingest the medium when acclimated to sea water.6.6. In Uca pugilator 86 per cent of the water influx is via the gills, 3 per cent is via drinking and 11 per cent is via the exoskeleton.
Article
An 8-week feeding trial was conducted to determine the threonine requirement of juvenile Pacific white shrimp Litopenaeus vannamei (Boone) in low-salinity water (0.50–1.50 g L−1). Diets 1–6 were formulated to contain 360 g kg−1 crude protein with fish meal, wheat gluten and pre-coated crystalline amino acids with six graded levels of l-threonine (9.9–19.0 g kg−1 dry diet). Diet 7, which was served as a reference, contained only intact proteins (fish meal and wheat gluten). Each diet was randomly assigned to triplicate groups of 30 shrimps (0.48±0.01 g), each four times daily. Shrimps fed the reference diet had similar growth performance and feed utilization efficiency compared with shrimps fed the diets containing 13.3 g kg−1 or higher threonine. Maximum specific growth rate (SGR) and protein efficiency ratio were obtained at 14.6 g kg−1 dietary threonine, and increasing threonine beyond this level did not result in a better performance. Body compositions, triacyglycerol and total protein concentrations in haemolymph were significantly affected by the threonine level; however, the threonine contents in muscle, aspartate aminotransferase and alanine aminotransferase activities in haemolymph were not influenced by the dietary threonine levels. Broken-line regression analysis on SGR indicated that optimal dietary threonine requirement for L. vannamei was 13.6 g kg−1 dry diet (37.8 g kg−1 dietary protein).
Article
Atlantic salmon with body weight of 493 g were fed 6 graded levels of methionine in diets based on plant proteins for a period of 85 days with the aim to test whether methionine intake affected growth, nutrient accretion and hepatic sulphur metabolism. A negative control based on a mixture of plant proteins with low fish meal inclusion (5%) containing 1.64 g methionine 16 g− 1 N was added five levels of dl-methionine resulting in dose levels from 1.64 to 2.98 g methionine 16 g− 1 N. A control feed based on fish meal (26%) and plant proteins (44.9%) containing 2.30 g methionine 16 g− 1 N was used as a control for growth performance. Feed intake and thus growth was generally lower in fish fed the plant protein based diets, while digestibility of amino acids was higher in fish fed the test diets as compared to those fed the fish meal based positive control diet. However, no significant differences in either feed intake or growth were present in fish fed either of the test diets containing graded levels of methionine. Neither carcass protein or lipid retention was affected by methionine intake as confirmed by the unaffected mRNA levels of growth hormone-insulin-like growth factor in hepatic and muscle tissues. Hepatic size as well as transsulfuration was significantly affected by methionine intake. Thus it is concluded that nutrient accretion was not the main effect of methionine intake (ranging from 35 to 90 mg fish− 1 day− 1). Rather methionine is essential to secure high synthesis of activated methyl groups for methylation reactions ensuring a healthy fish not developing increased liver size. Intakes exceeding 60 to 70 mg methionine daily in the fast growing seawater period results in increased transsulfuration analysed as increased hepatic taurine production keeping the hepatic free methionine constant at all intakes.
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Nine commercial feeding attractants and stimulants for Litopenaeus vannamei were evaluated by observation of behavioral responses in animals allotted in one Y-maze aquarium apparatus. In the validation phase, fishmeal–Brazilian origin (FMBO); fishmeal–Peruvian origin (FMPO); blood meal (BM), meat and bone meal (MBM), squid meal (SM), fish oil (FO) and fish solubles (FS) were evaluated. There was also a control without stimulatory raw material. The tested materials were included at 3% in neutral gelatin pellets (wet basis). In each behavioral observation, two different ingredients were offered at the same time in equal quantities, being allotted in the end of each chamber's arm. In Phase II after system validation, the following commercial attractants were tested: 80% crude protein (CP) vegetable dried biomass (VDB80), 68% CP vegetable dried biomass + glutamate + betaine (VDB68), complex of amino acids (alanine, valine, glycine, proline, serine, histidine, glutamic acid, tyrosine and betaine) with enzymatically digested bivalve mollusk (CAA), condensed fish soluble protein (CFSP), squid liver meal (SLM), betaine (Bet), dried fish solubles–low biogenic amines (DFSLB), dried fish solubles–high biogenic amines (DFSHB) and whole squid protein hydrolysate (WSPH). Attractants were used at a 3% level wet basis with neutral gelatin, without any additional ingredient source available. The best four commercial attractants from this phase (CAA, CFSP, SLM and WSPH) were compared under 0.5% and 1.0% levels. In Phase I of the study, a higher percentage of choices were observed for FMPO and FMBO. BM and FO were the least chosen ingredients. In Phase II, the worst results were observed for Bet, DFSHB and, mainly, for VDB80 and VDB68. When two-by-two comparisons were performed, results suggested that CFSP and CAA were the best commercial attractants tested. In the last phase, both CFSP and CAA at 1.0% level were significantly more chosen by shrimp than CFSP (0.5%), SLM (0.5 or 1.0%) or WSPH (0.5 or 1.0%). At both 0.5% and 1.0% levels, shrimp spent a similar amount of time feeding on CFSP and CAA. However, only CAA was statistically better than SLM and WSPH together. Further work is required to better elucidate the chemical drivers of chemostimulation for L. vannamei for each one of the attractants tested.
Article
This study evaluates the influence of both dietary protein and methionine on amino acid trans- and deamination (alanine aminotransferase, ALAT and glutamate dehydrogenase, GDH) in three tissues (muscle, hepatopancreas, gills) of the marine black tiger shrimp (Penaeus monodon). Shrimp (2.4 g) were fed one of the six semi-purified diets containing 14, 34 or 54% crude protein (% dry matter) with two levels of methionine (normal or 30% reduced) for 6 weeks. Both ALAT and GDH activities were the highest in the muscle. ALAT activity in muscle significantly decreased when feeding the low vs. high protein diets. Compared to those fed the intermediate protein level, GDH activity in muscle decreased (by 35%) when fed the low and increased (by 26%) when fed the high protein diets (P < 0.05). A significant interaction between dietary protein and methionine was observed on GDH activity in gills which, due to the relative methionine deficiency, increased 4-fold at the intermediate protein level. In summary, our results demonstrate for the first time the capacity of up and downregulation of enzyme activity by dietary protein levels in the muscle of P. monodon, and the active role played by branchial tissue in ammoniogenesis in response to a relative indispensable amino acid (methionine) deficiency.
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In recent years in NE Brazil, attempts to increase productivity in extensive marine shrimp farms has focused attention on semi-intensive cultivation methods with native species. The present study was initiated to investigate the diet of Penaeus subtilis under semi-intensive conditions over a complete growth cycle. The experiment was conducted at a commercial shrimp farm on the NE Brazilian coast. The investigation focused on the analysis of stomach contents and stable carbon isotope ratios. Naturally occurring pond biota was the major food source for P. subtilis observed throughout the study. Formulated food constituted 15.61% of the stomach contents (5.99% of stomach volume), accounting for 24.91% of the carbon growth, with the remainder attributed to natural food (average 75.09%). Polychaetes were the most important food type, representing 80.83% of all prey ingested (32.55% of the total food consumed). In the initial growth stages, P. subtilis displayed pronounced detritivorous feeding behaviour. As the shrimp grew, prey organisms were consumed in greater amounts, revealing a more carnivorous habit. Overall, a benthic omnivorous opportunist feeding behaviour was observed.
Article
Tissue concentrations of both homocysteine (Hcy) and cysteine (Cys) are maintained at low levels by regulated production and efficient removal of these thiols. The regulation of the metabolism of methionine and Cys is discussed from the standpoint of maintaining low levels of Hcy and Cys while, at the same time, ensuring an adequate supply of these thiols for their essential functions. S-Adenosylmethionine coordinately regulates the flux through remethylation and transsulfuration, and glycine N-methyltransferase regulates flux through transmethylation and hence the S-adenosylmethionine/S-adenosylhomocysteine ratio. Cystathionine beta-synthase activity is also regulated in response to the redox environment, and transcription of the gene is hormonally regulated in response to fuel supply (insulin, glucagon, and glucocorticoids). The H2S-producing capacity of cystathionine gamma-lyase may be regulated in response to nitric oxide. Cys is substrate for a variety of anabolic and catabolic enzymes. Its concentration is regulated primarily by hepatic Cys dioxygenase; the level of Cys dioxygenase is upregulated in a Cys-responsive manner via a decrease in the rate of polyubiquitination and, hence, degradation by the 26S proteasome.
Article
Animal studies have shown that several methionine (Met) and cysteine (Cys) analogs or precursors have L-Met- and L-Cys-sparing activity. Relative oral bioavailability (RBV) values, with the L-isomer of Met and Cys set at 100% (isosulfurous basis), are near 100% for D-Met for animals but only about 30% for humans. Both the OH and keto analogs of Met have high RBV-sparing values, as does N-acetyl-L-Met (the D-isomer of acetylated Met has no bioactivity). L-Homocysteine has an RBV value of about 65% for Met sparing in rats and chicks, but D-homocysteine has little if any Met-sparing activity. S-Methyl-L-Met can partially spare Met, but only when fed under dietary conditions of choline/betaine deficiency. Relative to L-Cys, high RBV values exist for L-cystine, N-acetyl-L-Cys, L-homocysteine, L-Met, and glutathione, but D-cystine, the keto analog of Cys, L-cysteic acid, and taurine have no Cys-sparing activity. l-2-Oxothiazolidine-4-carboxylate has an RBV value of 75%, D-homocysteine 70%, and DL-lanthionine 35% as Cys precursors. Under dietary conditions of Cys deficiency and very low inorganic sulfate (SO4) ingestion, dietary SO4 supplementation has been shown to reduce the Cys requirement of several animal species as well as humans. Excessive ingestion of Met, Cys, or cystine has also been studied extensively in experimental animals, and these sulfur amino acids (SAA) are well established as being among the most toxic of all amino acids that have been studied. Even though Cys and its oxidized product (cystine) are equally efficacious at levels at or below their dietary requirements for maximal growth, Cys is far more toxic than cystine when administered orally in the pharmacologic dosing range. Isosulfurous (excess) levels of cystine, N-acetyl-L-Cys, or glutathione are far less growth depressing than L-Cys when 6 to 10 times the minimally required level of these SAA compounds are fed to chicks.
  • F N Façanha
F.N. Façanha et al. / Aquaculture 463 (2016) 16–21
Estimation of feed level of methionine by Litopenaeus vannamei (Boone) using covalently-attached and crystalline sources in low-protein semi purified diets
  • J M Fox
  • A Lawrence
  • S Patnaik
  • I Forster
  • Z Y Ju
  • W Dominy
Fox, J.M., Lawrence, A., Patnaik, S., Forster, I., Ju, Z.Y., Dominy, W., 2010. Estimation of feed level of methionine by Litopenaeus vannamei (Boone) using covalently-attached and crystalline sources in low-protein semi purified diets. In: Cruz-Suárez, L.E., Ricque-Marie, D., Tapia-Salazar, M., Nieto-López, M.G., Villarreal-Cavazos, D.A., Gamboa-Delgado, J. (Eds.), Avances en Nutrición Acuícola 10. Memorias del Décimo Simposio Internacional de Nutrición Acuícola, San Nicolás de los Garza, pp. 232-249.
Nutrient Requirements of Fish and Shrimp. The National Academies Press
NRC, 2011. Nutrient Requirements of Fish and Shrimp. The National Academies Press, Washington, D.C., USA, National Research Council 376pp.