Trond Storebakken

• Dr Scient
• Professor (Full) at Norwegian University of Life Sciences

Lower energy consumption for producing feed pellets is an important part of the economy in the feed mill. The same is if physical pellet quality is degraded. The interest in using of novel ingredients is increasing due to requirements for the sustainable development goals. Defatted microalgae as by-product from biodiesel production is one of many n...

The aim of this study was to investigate how dietary conventional (CSW) or hydrolyzed (HSW) stickwater from skipjack tuna by-product affected growth and feed utilization of hybrid grouper. Nine isonitrogenous (500–505 g crude protein (CP) (kg DM)⁻¹) and isoenergetic (20.3–20.9 MJ gross energy (GE) (kg DM)⁻¹) extruded diets were formulated. A contro...

Actinobacteria and cyanobacteria accounted for less than 1% of total of bacteria in water in a recirculated aquaculture system (RAS) during a 15‐week feeding trial with 0.11‐g Japanese seabass. Resulting concentration of geosmin and 2‐methylisoborneol (2‐MIB) in RAS water was 169 and 45 ng L−1, sufficient to produce strong off‐flavour. The seabass...

This study develops and analyses a conflict resolution model surrounding the rejection of a climate-smart fisheries technologies project in Chipala village, Nkhotakota district, Malawi. Solar tent driers and improved smoking kilns were introduced by the SEED Fish project in Chipala and Vinthenga villages. However, the technologies are not in use in...

A new non-GM cultivar of soybean, named Triple Null (TN), devoid of Kunitz trypsin inhibitor, lectin and the allergen P34/Gly m Bd 30 k has been developed from a commercial cultivar. Use of standard soybean meals in diets for Atlantic salmon most often induces distal intestinal inflammation whereas soy protein concentrate (SPC), in which several an...

The study was carried out to evaluate wedge wire screen as a potential tool for collecting fish faeces from the tank outlet water. Apparent digestibility (AD) estimates of carbon (ADC), nitrogen (ADN), sulphur (ADS), organic material (ADORG) and individual amino acids obtained by the wire screen were compared with stripping. Three diets, with fishm...

A novel toxicity-warning sensor for water quality monitoring in recirculating aquaculture systems (RAS) is presented. The design of the sensor system mainly comprises a whole-cell biosensor. Aliivibrio fischeri, a luminescent bacterium widely used in toxicity analysis, was tested for a mixture of known fish-health stressors, namely nitrite, un-ioni...

Recirculating Aquaculture Systems (RAS) present an innovative, clean and practical way of producing fish intensively. Stress caused by high concentrations of chemical species such as nitrite and un-ionized ammonia, affects fish health and growth and therefore the sustainability of RAS would require an online monitoring for those chemical stressors....

Global environmental changes have negatively affected many food systems while the demand for food has continued to rise. An urgent need exists to identify other sustainable means of producing food. This is a case in Malawi, where capture fisheries and agriculture are not supplying sufficient food. Fish farming food systems by communities who rely o...

The effects of climate change have negatively affected Malawi's agricultural production. In this context, fisheries have been providing alternative livelihoods. However, there is a knowledge gap around the responses of small-scale fishers to climate-related changes. Therefore, a study was conducted on the Western shores of Lake Malawi between Augus...

The aim of this experiment was to define the optimal mixtures of plant protein concentrates in an extruded, fish meal free diet for rainbow trout. Three essential amino acids (EAA) and taurine-fortified plant protein mixtures (P-MIX, C-MIX, and S-MIX) were prepared by mixing four plant protein concentrates (pea protein concentrate (PPC), canola pro...

A 60-day feeding experiment was carried out to investigate the effects of including lupin protein concentrate (LPC) and pea protein concentrate (PPC) in multiple essential amino acid-supplemented extruded diets for black sea bream (Acanthopagrus schlegeli). Nine diets, including eight diets formulated to contain four mixtures of LPC and PPC (L/P ra...

Antarctic krill (Euphausia superba) and other marine zooplankton may contain high levels of fluoride. The aim of the present experiment was to determine whether dietary fluoride from Antarctic krill at levels similar to the old and the new EU allowable limits in fish feeds (150 and 350 mg kg-1) would induce kidney lesions in freshwater-reared Atlan...

This study evaluated the effects of sparteine, a lupin alkaloid, on growth and organ histology in rainbow trout. Eight diets with increasing concentrations of sparteine (0, 50, 100, 250, 500, 1000, 2500 and 5000 mg kg−1) were fed to triplicate groups of 61‐g fish for 62 days. Survival was not affected by the dietary treatments. Weight gain, feed co...

The aim of this experiment was to determine the optimal inclusion level and ratio of lupin (LPC) and pea pro-tein concentrates (PPC) in multiple essential amino acid-supplemented diets for rainbow trout (Oncor-hynchus mykiss). Nine extruded diets, including eight plant protein based diets formulated using four mixtures of LPC and PPC (L/P ratio, 3:...

Two experiments were conducted to investigate effects of feed processing conditions and potassium diformate (KDF) supplementation on apparent digestibility of nutrients in Atlantic salmon (Salmo salar) and physical quality of extruded feed. In Exp. 1, diets with raw or expander pretreated full‐fat soybean meal (FFSBM) at 100 or 120 °C were extruded...

The use of Antarctic krill (Euphausia superba) in fish feeds may be limited by a high fluoride level. The aim of this experiment was to investigate the bioavailability of dietary fluoride from either krill shell or sodium fluoride (NaF) to rainbow trout (Oncorhynchus mykiss). The second aim was to investigate if the fluoride bioavailability was aff...

The objective of the experiment was to evaluate the effects of ingredient, extrusion temperature, and the conjugated acid salt sodium diformate (HCOOH··HCOO-Na; NaDF) on apparent nutrient digestibility and physical quality of diets for rainbow trout. The experiment had a 23 factorial design with two dietary ingredient sources (fish meal [FM] and ba...

This experiment investigated the effect of increasing dietary doses of lupinine, the main quinolizidine alkaloid in Lupinus luteus, on feed intake, growth performance, tissue histology and nutritional composition of rainbow trout (Oncorhynchus mykiss). Duplicate groups of rainbow trout (initial body weight of 330g) were fed extruded fish meal based...

The aim of the study was to investigate how the replacement of LT-fish meal by a 3.5:1 mixture of an experimentally produced partially deshelled krill meal (PDKM) and a pea protein concentrate (PPC) affected growth rate, digestibility of main nutrients and minerals, fluoride accumulation and histology in Atlantic salmon (Salmo salar). Five extruded...

This study investigated the effects of raffinose, stachyose either alone or in combination, and the role of soya-saponins in combination with these oligosaccharides, in diets for Atlantic salmon on nutrient digestibilities, growth performance and morphological changes of the gastrointestinal tract. The experiment was carried out using triplicate gr...

Two experiments were conducted to evaluate the effects of adding an organic acid salt blend (OAB, 10g acid moiety kg−1 of a mixture of sodium formate and butyrate, ratio 2:1) and plant proteins (soybean meal and pea protein concentrate) to diets for rainbow trout (Oncorhynchus mykiss) reared in freshwater. The experiments were designed according to...

The aim of this study was to investigate how diets containing partially deshelled or whole krill meals affected growth, digestibility of main nutrients, faecal excretion of minerals, fluoride accumulation, and organ indices and health parameters in Atlantic salmon (Salmo salar). Three extruded diets were fed for 100 days to salmon with an average w...

This experiment investigated the physical qualities (‘Holmen’ durability; ‘tumbling box’ durability; and pellet strength, length and diameter) of extruded fishmeal-based feeds produced using different starch sources, screw configurations, with or without steam injected in the barrel. The starch sources tested were native or pre-gelatinized potato s...

The effect of pea protein concentrate in diets for Atlantic salmon (Salmo salar) on growth performance, nutrient digestibility, carcass composition, blood chemistry, histology of the gastro-intestinal tract (GIT), and physical feed quality was investigated. A 12-week study was conducted using triplicate groups of Atlantic salmon with 0.16 kg initia...

The study was designed to investigate effects of processing of soybean meal on physical quality of extruded fish feed. Three diets were produced; one fish meal (FM) based control diet, and two diets with 40% amino acids from FM replaced by defatted, toasted soybean meal (SBM) or defatted, untoasted soybean meal (white flakes, WF). The diets were ex...

Accumulation of 14C in various tissues and organs was studied in three different groups of 0.8-kg Atlantic salmon Salmo salar force-fed with 14C1-glucose in order to evaluate if metabolism of glucose depended on adaptation to dietary carbohydrate level. The salmon had been fed diets supplemented with 0, 100 and 200 g maize dextrin kg−1 for 10 month...

The aim of this experiment was to study the effect of defatted soybean meal (SBM) on lipid digestibility, bile acid level and morphological changes in the distal intestine (DI) in rainbow trout, and to assess whether the lipid digestibility and bile acid level are affected by the morphological changes in the DI. Triplicate groups of 0.35-kg trout w...

Yellow lupin (Lupinus luteus) is a promising source of protein in feeds for carnivorous fish. However, the high content of alkaloids may limit its potential for use. Lupinine is the main quinolizidine alkaloid in several varieties of Lupinus luteus. It has been reported to be highly toxic for bacteria and invertebrates, however no information is av...

Juvenile cobias, Rachycentron canadum, were fed extruded diets containing toasted defatted soybean meal (SBM) or untoasted defatted SBM [white flakes (WF)] to study growth and feed conversion, and to study if SBM induces morphological changes in the gastrointestinal (GI) tract. Three diets were produced: a fish meal-based control diet (FM diet) wit...

The study was conducted to examine if cellulose affected physical characteristics of extruded feed and nutrient digestibilities in rainbow trout. Five diets with cellulose inclusion levels ranging from 0 to 150 g kg− 1 were produced with a target apparent bulk density of 520 g l− 1 and fed to triplicate groups of fish (average weight 0.45 kg) twice...

Ten different plant protein and/or starch sources were studied in a 5-week experiment with triplicate groups of 0.7-kg Atlantic salmon in seawater, pre-adapted to a diet with fish meal, faba beans, sunflower cake, and wheat gluten as sources of protein and starch. The experimental ingredients were corn gluten, defatted soybean, defatted sunflower,...

Duplicate groups of Atlantic salmon (Salmo salar), kept in saltwater, were fed fish meal based cold-pelleted diets where graded levels of native or extruded non-starch polysaccharides (NSP) from soybeans replaced cellulose, at a total NSP level of 100 g kg− 1 for 28 days. The study also included a diet where defatted soybean meal (SBM) constituted...

In this trial with Atlantic salmon (initial weight, 142 g) raised in 8 °C seawater, the effect of coating or online pre-treatment with phytase was investigated. Four diets were produced: one fishmeal (FM) diet and three diets — SPC, SPC-P and SPC-PPT — in which 60% of the protein from fishmeal was replaced by soy protein concentrate. The SPC diet d...

The effects of replacing soybean meal or fish meal with 2, 4 or 6% bacterial protein meal (BPM) on growth performance, ileal digestibility of amino acids and sensory quality of meat, were examined using 630 broiler chickens. Weight gain from 7-32 days of age did not differ significantly among the treatments. Efficiency of feed conversion was increa...

The effect of basic bacterial protein meal (BPM) and bacterial protein meal homogenate (HOM) on length, expansion, density, sinking rate, fat leakage, durability, and breaking force of extruded dog food and salmon feed exposed to mild and moderate processing conditions was evaluated. The treatment consisted of a control diet and four test diets whe...

The effects of graded levels of phytic acid on skeletal development and mineral deposition were investigated in an 80 day feeding trial with Atlantic salmon (Salmo salar L.) parr. The level of phytic acid had no significant effect on the phosphorus (P) content of either whole body or vertebral column of Atlantic salmon. Negative effects of high phy...

A study was conducted to compare coefficient of total tract apparent digestibility (CTTAD) of diets where high-quality (LT) fish meal (FM) were partly replaced with basic bacterial protein meal (BPM) and autolyzed bacterial protein meal (BPA) in a carnivorous mammal (mink) and fish (rainbow trout). In mink, both unprocessed meal and extruded diets...

The optimal conditions for degradation of phytate (IP6, myo-inositol hexaphosphate) in a mixture of ground wheat and ground defatted soybeans (1:2, w/w) with added exogenous E. coli phytase were investigated at different temperatures (45, 60, 75, and 95 degrees C), moisture levels (25%, 35%, and 45%), and retention times (2-45 min). All treatment c...

Color of wild, astaxanthin pigmented, and farmed, canthaxanthin pigmented, Atlantic salmon (Salmon salar) was evaluated by spectroscopy and visual sensory analyses. A more yellow hue in farmed salmon color compared with wild salmon was found in acetone extracts of raw salmon flesh and by visual sensory analyses of raw, baked and smoked salmon flesh...

The effects of frozen storage (3 and 6 months at −20 and −80°C) on stability of carotenoids and color [CIE, (1976) L*a*b* and H(°)ab] in vacuum-packed fillets of rainbow trout were studied in a paired-sample experiment. The trout were fed diets containing astaxanthin or canthaxanthin at different water salinities and temperatures. Carotenoids in th...

Duplicate groups of Atlantic salmon (36.4 ± 0.1 g) were fed graded levels of phytic acid (IP6) for 80 days. The basal diet, to which different levels of sodium phytate were added to obtain 0, 1.0, 2.1, 4.7, 10.0 and 20.7 g IP6 kg− 1, contained fish meal, fish oil and wheat starch. The dose–response relationships between IP6 and feed intake, growth,...

An experiment was carried out to study the nutritional value of solvent extracted, toasted soybean meal (SBM) and solvent extracted, untoasted soy “white flakes” (WF) partly replacing high-quality fish meal (FM) in extruded diets for rainbow trout. Particularly, we wanted to find out if feed extrusion provides sufficient heat to reduce the soybean...

The study was designed to investigate disulfide bond (SS) digestibility, the effect of extrusion on dietary SS content, and the relationship between dietary SS content and nitrogen (N) and SS digestibility. Three high-quality fish meal-based diets were produced; one control diet (FM) and two diets with 40% of amino acids from fish meal replaced by...

Enhancement of fish feed extrusion-technology and improvements of technical pellet quality requires knowledge about causal connections amongst variables of processing condition and raw materials, and how these connections can be elucidated by measurements. Weibull analysis of feed pellet tensile strengths may represent one possible measurement tool...

The effects of moist extrusion processing of diets containing fish meal (FM) and conventional defatted soybean meal (SBM) or untoasted defatted soybean meal (white flakes [WF]) on amino acid composition, trypsin inhibitor activity (TIA), and apparent total tract digestibility of nutrients were studied. Three diets with the nutritional characteristi...

A total of 832 samples of soybeans were screened by near-infrared (NIR) reflectance spectroscopy, to identify soybean samples with a lower content of oligosaccharides and nonstarch polysaccharides (NSP). Of these, 38 samples were identified on the basis of variation in protein content and agronomic value and submitted to high-resolution NIR spectro...

Digestibility and utilization of a fishmeal-based diet extruded at 103 or 137 °C were examined. Each of the diets was fed to 0.5-kg rainbow trout in nine tanks supplied with freshwater. Specific growth rate was significantly (P < 0.05) elevated for trout fed the feed extruded at 137 °C. The apparent digestibilities of protein and energy, feed conve...

An 8-week growth trial was conducted to study carbohydrate utilization by white sturgeon fed diets containing glucose or hydrolyzed potato starch (HPS). Four diets supplemented with 15% or 30% of glucose or HPS and a control diet with no added carbohydrate were each fed to triplicate groups of fish. The diets were processed by a 3-min 80 °C microwa...

The effect of starvation-refeeding on protein mobilization in the lateral line, lateral (midway between lateral line and dorsum) and dorsal parts of white sturgeon (Acipenser transmonlanus) white epaxial muscle (type IIB) were compared by measuring muscle cross-sectional fibre areas. Effects on red (type I) and pink (type IIA) muscle were also stud...

Bacterial protein meal (BPM) produced on natural gas was evaluated with respect to growth, nutrient digestibilities, feed conversion ratios, sensory quality, and histopathological indices in Atlantic salmon in saltwater. In the extruded diets, experimentally produced BPM accounted for 0, 10, or 20% of the ingredients or 0, 17.2, or 33.1% of dietary...

An experiment was carried out to evaluate the effect of different extrusion processes on digestibility of a fish-meal-based diet fed to mink. The feed was processed in a twin-screw extruder with the exit temperatures of the meal of 100, 125 or 150°C. Feed production was carried out three times, using different extrusion conditions to achieve the ta...

Bacterial protein meal (BPM) produced on natural gas was evaluated with respect to growth, survival, body composition and histopathological indices in Atlantic salmon during the freshwater stage. In the diets, experimentally produced bacterial protein accounted for 0%, 6.25%, 12.5%, 25% and 50% of total dietary amino acids gradually replacing high-...

The aims of this study were to assess the effects of enzymatic cell wall disruption and feed extrusion temperature on utilization of astaxanthin from red yeast (Xanthophyllomyces dendrorhous, formerly Phaffia rhodozyma) supplied to experimental diets for rainbow trout. The red yeast was subjected to three different degrees of enzymatic cell wall di...

The effect of different degrees of enzymatic cell wall disruption (45%, 70%, and 97%) of red yeast (Xanthophyllomyces dendrorhous, formerly Phaffia rhodozyma) and extruder temperatures (102, 121, and 137 °C) on astaxanthin stability and formation of astaxanthin Z-isomers was determined during extruded fish feed production. Enzymatic cell wall disru...

Atlantic salmon, Salmo salar L., fingerlings with a mean weight of 1.5 g were fed one of four casein-gelatine-based purified diets supplemented with soya lecithin (LC) and choline chloride (CH) for 84 days. The diets were supplemented with either: 0 g kg−1 CH and 0 g kg−1 LC, 0 g kg−1 CH and 30 g kg−1 LC, or 5 g kg−1 CH and 0 g kg−1 LC, or 5 g kg−1...

Four diets formulated for salmon were fed to 0.11 kg white sturgeon, Acipenser transmontanus Richardson, for 8 weeks. Dietary compositions ranged from 258 to 402 g lipid kg−1, 535–378 g protein kg−1 and 22.7–14.4 g protein MJ−1 gross energy.Fish in all treatments grew rapidly, utilized the diets efficiently and had body compositions similar to what...

Bacterial protein meal (BPM) produced from natural gas by Methylococcus capsulatus (Bath), Alcaligenes acidovorans, Bacillus brevis and Bacillus firmus was studied as a protein source for broiler chickens. Three experiments from day-old to slaughter at 35 d were carried out. In exp. 1, BPM was fed at 0, 20, 40, 60, 80 and 100 g kg-1 diet (as fed) r...

A fish meal/wheat flour based dry ingredient mix was extruded at three different temperatures (100, 125 and 150 °C), by varying extrusion conditions according to two different methods. Employing method 1, the temperature of the conditioner, torque, screw speed, pressure, feed rate and process water of the extruder were varied. Whereas in method 2,...

The effects of lactic acid fermentation of wheat and barley whole meal flours (WMF) on digestibility parameters in Atlantic salmon were studied. The WMFs were inoculated with a specific Lactobacillus strain and fermented for 16 h at 30 °C prior to mixing with other feed ingredients and processing by extrusion. Fermentation of the WMFs significantly...

Four extruded diets, differing in grain supplementation, were fed to triplicate groups of Atlantic salmon (Salmo salar, L.) with a mean weight of 0.5 kg in a digestibility trial. The diets contained 100 or 150 g kg−1 of precooked rye or wheat, replacing fish meal. There were no significant differences in apparent digestibility coefficients (ADC) of...

This book contains articles on the nutrient requirements and feeding of finfish for aquaculture. Topics include the following: introduction to fish nutrition; marine fishes (European sea bass, Asian sea bass, red sea bream, gilt-head sea bream, Atlantic salmon, Atlantic halibut, Japanese flounder, North American flounder, yellowtail, red drum, sout...

The influence of dietary cholesterol (CHOL) and short-chain fatty acids (SCFA; sodium salts of acetic, propionic and butyric acid, 5:5:2 w/w/w) on growth, organ indices, macronutrient digestibility, and fatty acid composition of Atlantic salmon Salmo salar was investigated. Salmon (initial average weight 0.7 kg) held in seawater (7°C) for 175 days...

A 56-day growth trial was conducted to study the utilization of hydrolysed potato starch by juvenile Atlantic salmon Salmo salar L. using a restricted feeding regime. Two diets supplemented with either 15% or 30% hydrolysed potato starch and a control diet without carbohydrate supplementation were each fed to triplicate groups of salmon. Feeding ra...

To evaluate the importance of age and feed ration level (RL) on the composition of tissue fatty acid (FA) in rainbow trout (Oncorhynchus mykiss), fish were fed rations ranging from appreciable underfeeding to gross overfeeding in a longitudinal experiment lasting from start of feeding to onset of sexual maturation 2.4 years later. In order to study...

Feed intake, growth and feed utilization were studied in 14 full-sib family groups of Atlantic salmon (seven sires, two dams per sire, 30 fish per family), with an average initial body weight of 148 g. Each full-sib family was held in replicate tanks with fresh water for two subsequent 5-week periods. Body weight increased by 12–52%, and the averag...

Apparent absorption coefficients (AACs) of mineral elements (K, Na, Cu, Ca, Mg, Zn, Fe, Mn, P) were studied in 82 full-sib family groups of individually tagged Atlantic salmon (41 sires, 2 dams per sire, 7–27 fish per family), with an average weight of 4.6 kg. The fish were kept in one net-pen in seawater and fed a diet with Y2O3 as the inert marke...

This study investigated long-term effects on nutrient digestibility and protein and lipid growth of soy protein and lipid levels used in commercial grower diets for Atlantic salmon. Two series of extruded diets were formulated to contain either 45% protein and 32% lipid (medium fat) or 40% protein and 39% lipid (high fat). Each series consisted of...

This study was carried out to compare the responses of rainbow trout and Atlantic salmon to being fed defatted soybean meal. Two extruded experimental diets containing either low-temperature (LT)-fish meal as the sole protein ingredient or 32% fish meal and 30% soybean meal, were each fed to triplicate groups of 0.1 kg trout or 0.2 kg salmon mainta...

Trivalent oxides of yttrium and rare earth metals were evaluated as inert markers in apparent digestibility studies with salmonids in four experiments. In Experiment 1, 100 mg kg−1 of each of 15 oxides (Dy2O3, Er2O3, Eu2O3, Gd2O3, Ho2O3, La2O3, Lu2O3, Nd2O3, Pr2O3, Sc2O3, Sm2O3, Tb(III and IV) oxide, Tm2O3, Y2O3 and Yb2O3) were included in a feed f...

An experiment with 0.2-kg Atlantic salmon, Salmo salar in saltwater was conducted to determine if the fish could grow normally, and maintain normal nitrogen (N) and mineral balance when fed a diet with the majority of the protein (75%) derived from soy-protein concentrate (SPC). The two diets contained 50% SPC and 15% fish meal (FM) or 60% FM as th...

Apparent digestibility coefficients (ADCs) of macronutrients and energy, and apparent absorption coefficients (AACs) of amino acids and elements were assessed in an experiment with 0.9 kg Atlantic salmon reared in saltwater tanks. Duplicate groups of fish were fed five diets, where 0, 6.25, 12.5, 25 and 50% of crude protein (CP) from fish meal (FM)...

The time of appearance in blood, and transport of astaxanthin, and catabolic transformation of astaxanthin to idoxanthin were investigated in Atlantic salmon (Salmo salar) that had been force-fed a single dose of 14C-astaxanthin. In addition to the LPs, a major protein, associated with radiolabeled astaxanthin was detected. The maximum level of rad...

This investigation examines the influence of implants containing 11-ketotestosterone (11KT), 17-estradiol (E2), and 3,5,3-triiodo-l-thyronine (T3) on astaxanthin metabolism in sexually immature individually tagged Arctic charr. The fish (initial average weight 427g) were maintained in freshwater for 40days, and weekly implanted intraperitoneally wi...

Total tract digestibility in Atlantic salmon and ileal digestibility in chicken were assessed from diets with different soyabean products (hulled, toasted, extracted, SBM; reduced oligosaccharide content, ROM; ethanol-extracted protein concentrate, SPC; isolated protein, ISP). The concentration of dietary fibre was highest in SBM and ROM, while it...

Gastrointestinal evacuation of Atlantic salmon was estimated using yttrium and ytterbium oxides (Y2O3 and Yb2O3) and collection of faeces from the outlet water of the tanks by sieving. The fish were fed three diets with different protein sources: fish meal (FM) (55% FM); soybean meal (SBM) (35% FM and 31% SBM); and bacterial meal (BM) (34% FM and 2...

Digestibility measurements obtained from four faecal collection methods were compared in two experiments with Atlantic salmon, reared in freshwater. The fish were fed three diets with different protein sources: a diet with 55% fish meal (FM); a diet with 35% FM and 31% soybean meal; and a diet with 34% FM and 20% bacterial meal. In Expt. 1, faecal...

The composition and amino acid digestibility of bacterial protein meal (BPM) produced by Methylococcus capsulatus (Bath), Alcaligenes acidovorans, Bacillus brevis, and Bacillus firmus grown on natural gas were studied. The BPM contained 959gkg−1 dry matter, 702gkg−1 crude protein, 103gkg−1 fat, and 95gkg−1 nucleic acids. The amino acid composition...

The aim of the experiment was to determine if salinity, dietary carbohydrate source, and dietary carbohydrate concentration affected the digestibility of macronutrients and energy in rainbow trout, and also to determine if there were interactions between these factors. The trout, reared in freshwater or saltwater, were fed four diets, containing mo...

The objectives of the experiment were to examine palatability of diets containing two different soybean meals in Atlantic salmon (Salmo salar) previously fed fish meal diets, and to separate effects of feed intake and physiological factors in soybean meal on growth and feed conversion. A fish meal-based control diet (FM) and two diets with 40% of t...

An experiment with 0.1-kg Atlantic salmon in saltwater was conducted to evaluate soy-protein concentrate as a source of dietary protein and to determine if phytase treatment of soy concentrate affected the availability of protein and essential elements. Three diets were fed to triplicate groups of fish for 84 days: Diet 1 with 61% fish meal, Diet 2...

The objective of this experiment was to establish whether absorption and deposition of astaxanthin was affected by feeding Atlantic salmon alternate meals with or without astaxanthin. Duplicate groups of salmon (35 fish per tank) with an initial weight of ca. 0.5 kg, were maintained in saltwater at ca. 7.5°C. The fish were fed 8 meals a day within...

Two cold-pelleted diets containing either 36.9 or 35.4 mg kg−1 of predominantly all-E-astaxanthin (97% of total astaxanthin) or a mixture of all-E- and Z-astaxanthin (64 and 36%, respectively), were fed to duplicate groups of rainbow trout (Oncorhynchus mykiss) in freshwater (initial weight 0.4 kg) for 69 days. Average final weight was ca. 1.0 kg f...

Atlantic salmon fed for 9.5 months, diets containing medium (MF, 32%) or high (HF; 39%) fat levels with fish meal (FM) or 10% of the FM protein replaced by full-fat soybean meal (FFSM) protein were analyzed by sensory profiling. No significant differences were observed in sensory characteristics. Fish fed HF diets had more total carcass lipid, larg...

Three experiments were conducted with rainbow trout maintained in fresh water. In Experiment 1, growth was measured in groups of 34-g trout fed either a fish meal control diet (Diet 1) or a diet containing 60% soybean meal (Diet 2) for two periods of 28 days each. In Experiment 2, Diets 1 and 2 were fed to groups of 100-g trout for 10 days prior to...

A 10 week study was conducted to determine the effect of starvation on morphological and biochemical parameters in subyearling white sturgeon. The fish were implanted with passive integrated transponder tags so that body weight change of individual fish could be determined. Ten fish were sampled once every 2 weeks. Carcass:body weight percentage, v...

Three year-classes (1 +, 2 + and 3 +) of Arctic charr were fed diets containing 63 or 114 mg astaxanthin kg−1 for 3 months. Effects of fish size and dietary inclusion level of astaxanthin on carotenoid composition of the flesh were examined.Idoxanthin (3,3′,4′-trihydroxy-β,β-carotene-4-one), a metabolite of astaxanthin, was identified by UV-visible...

Triplicate groups of Atlantic salmon fry with an initial weight of 0.15 g were fed four experimental diets for 20 weeks. The diets were: a commercial steam pelleted salmon starter (Diet 1); a Norse-LT 94® fish-meal based control diet (Diet 2); 5% of amino acid nitrogen in Diet 2 replaced by amino acid nitrogen from fish protein hydrolyzate (Diet 3)...

Atlantic salmon with an initial weight of 1.1 kg were fed three extruded diets with different amounts of astaxanthin (5, 51 and 61 mg kg−1) in an experiment lasting for 26 weeks. Availability of astaxanthin was assessed after collection of blood plasma from 2 × 10 fish per pen (three pens per diet; two groups of fish per pen, previously unpigmented...

The digestibility of astaxanthin and canthaxanthin in rainbow trout was studied in two different experiments. In the first experiment, the trout were fed, at a rate of 1.0% body weight/day (BW/d), diets containing various concentrations (12.5, 25, 50, 100 and 200 mg carotenoid/kg feed) of astaxanthin or canthaxanthin in fresh water. The overall app...

Two dietary astaxanthin levels (63 and 114 mg kg−1) were fed to three year classes (1 +, 2 +, 3 +) of Arctic charr in a 25 weeks experiment. Growth were monitored, and at weeks 1, 13 and 25, samples were taken for analysis of total carotenoids in flesh, skin, fins and plasma.The average growth rates were 1.35, 0.73 and 0.44% d−1 for the 1 +, 2 + an...

Enzymatic changes that occur in the white somatic muscle of rainbow trout (Oncorhynchus mykiss) in response to spawning were investigated, and the evenness of their distribution across the ventral-dorsal plane of this muscle was assessed. Four enzymes that are involved in energy metabolism were measured (phosphofructokinase: glycolytic capacity, 3-...

A 16-wk experiment was conducted to compare the utilization of four carbohydrates by rainbow trout (Oncorhynchus mykiss) fed either continuously or four meals daily. The carbohydrates were glucose, maltose, dextrin and raw cornstarch, and were included at 32 g/100 g diet. Average initial body weight of the fish was 5.5 g, and fish were fed at a res...