Brown Fish Meal Research Articles

Effects of Brown Fishmeal on Growth Performance, Digestibility, and Lipid Metabolism of the Chinese Soft-Shelled Turtle (Pelodiscus sinensis).

The aim of this study was to evaluate the effect of brown fishmeal in replacement of white fishmeal in the diet of Chinese soft-shelled turtles and to find the optimal amount of brown fishmeal to add. Five experimental groups were set up and fed to animals, and they were composed by different proportions of white and brown fishmeal: G1 (30% white and 25% brown fishmeal), G2 (25% white and 30% brown fishmeal), G3 (20% white and 35% brown fishmeal), G4 (15% white and 40% brown fishmeal), G5 (10% white and 45% brown fishmeal). G1 is regarded as the control group. Turtles were randomly divided into five experimental groups with four replicates each. The experiment lasted 72days. The results showed that the WGR, SGR, FCR, and HSI of the G3 group were not significantly different from those of the control group (P > 0.05). In addition, brown fishmeal can increase the crude protein content in the muscles of them. Among the serum biochemical indices, there was no significant difference between the G3 group and the G1 group, except for the level of TG (P > 0.05). Meanwhile, the activities of AST, ALT, and CAT in the liver of the G3 group did not differ significantly from those of the G1 group (P > 0.05). However, the activities of ACP, AKP, and T-AOC were significantly decreased in the G3 group (P < 0.05). In addition, the alteration of fishmeal did not affect the digestive enzyme activities in the stomach, liver, and intestine, and there is no significant difference (P > 0.05). Importantly, with increasing brown fishmeal addition, the expression of Fas, Pparγ, Scd, and Stat3 showed a significant increase, while the expression of Bmp4 decreased significantly (P < 0.05). In this study, the addition of 20% white fishmeal and 35% brown fishmeal to the diet of Chinese soft-shelled turtles did not adversely affect growth performance. Therefore, 20% white fishmeal and 35% brown fishmeal are the most practical feed formulations for Chinese soft-shelled turtles in this study.

Effects of White Fish Meal Replaced by Low-Quality Brown Fish Meal with Compound Additives on Growth Performance and Intestinal Health of Juvenile American Eel (Anguilla rostrata).

With a reduced supply and increased price of white fish meal (WFM), the exploration of a practical strategy to replace WFM is urgent for sustainable eel culture. A 70-day feeding trial was conducted to evaluate the effects of replacing WFM with low-quality brown fish meal (LQBFM) with compound additives (CAs) on the growth performance and intestinal health of juvenile American eels (Anguilla rostrata). The 300 fish (11.02 ± 0.02 g/fish) were randomly distributed in triplicate to four groups (control group, LQBFM20+CAs group, LQBFM30+CAs group and LQBFM40+CAs group). They were fed the diets with LQBFM replacing WFM at 0, 20%, 30% and 40%, respectively. The CAs were a mixture of Macleaya cordata extract, grape seed proanthocyanidins and compound acidifiers; its level in the diets of the trial groups was 0.50%. No significant differences were found in the growth performance between the control and LQBFM20+CAs groups (p > 0.05), whereas those values were significantly decreased in LQBFM30+CAs and LQBFM40+CAs groups (p < 0.05). Compared to the control group, the activity of glutamic-pyruvic transaminase was significantly increased in LQBFM30+CAs and LQBFM40+CAs groups, while lysozyme activity and complement 3 level were significantly decreased in those two groups (p < 0.05). There were decreased antioxidant potential and intestinal morphological indexes in the LQBFM30+CAs and LQBFM40+CAs groups, and no significant differences in those parameters were observed between the control group and LQBFM20+CAs group (p > 0.05). The intestinal microbiota at the phylum level or genus level was beneficially regulated in the LQBFM20+CAs group; similar results were not shown in the LQBFM40+CAs group. In conclusion, with 0.50% CA supplementation in the diet, LQBFM could replace 20% of WFM without detrimental effects on the growth and intestinal health of juvenile American eels and replacing 30% and 40%WFM with LQBFM might exert negative effects on this fish species.

Apparent Digestibility of Nutrients in Thirteen Animal‐Based Feedstuffs by the Orange‐spotted Grouper Epinephelus coioides

AbstractIn this study, the apparent digestibility coefficients (ADCs) of 13 animal‐based feedstuffs were determined for a common aquaculture fish, the Orange‐spotted Grouper Epinephelus coioides. The feedstuffs included five kinds of fish meal (white fish meal [WFM]; low‐temperature‐steam‐dried brown fish meal [LTSBFM]; domestic flame‐dried fish meal; imported flame‐dried fish meal; miscellaneous fish meal [MFM]), two kinds of blood meal (spray‐dried hemoglobin meal; dried‐blood meal [DBM]), and six kinds of animal by‐product meal (chicken meal; meat and bone meal; pork meat meal; fermented feather meal [FFM]; hydrolyzed feather meal [HFM]; shrimp meal). Experimental diets were composed of reference diet at 699 g/kg, yttrium oxide at 1 g/kg (as a tracer), and each tested feedstuff at 300 g/kg. The ADCs of dry matter, crude protein, lipid, gross energy, phosphorus, and amino acids were determined for each experimental diet by the fecal sedimentation method. Overall, the ADCs of dry matter, crude protein, lipid, energy, phosphorus, and amino acids had ranges of 61.39–76.72, 72.23–91.96, 60.75–91.56, 45.20–88.45, 39.61–76.20, and 70.39–96.71%, respectively. The protein ADCs of the WFM (91.96%) and LTSBFM (91.28%) diets were significantly higher than those of the other feeds. The protein ADCs of the remaining tested diets were over 80%, except for those of the MFM, DBM, and HFM diets. The DBM and HFM diets each had the lowest and second‐lowest ADCs of crude protein, lipid, and energy. In conclusion, Orange‐spotted Grouper demonstrated high nutrient digestibility for the tested animal‐based feedstuffs except MFM, DBM, FFM, and HFM. This digestibility information can aid in the formulation of feed substitutes for least cost diets to be used with cultured Orange‐spotted Grouper.

Tuna by-product meal as a dietary protein source replacing fishmeal in juvenile Korean rockfish Sebastes schlegeli

This study was conducted to evaluate the use of tuna by-product meal (TBM) as a substitute for fishmeal in juvenile Korean rockfish (Sebastes schlegeli) diets. Five isonitrogenous (52% crude protein) and isocaloric (4.9 kcal/g) diets were prepared. Control diet (Con) was formulated to contain brown fishmeal, whereas 25, 50, 75, and 100% of fishmeal was substituted with the same percentage of TBM in the TBM25, TBM50, TBM75, and TBM100 diets, respectively. Three replicate groups of fish (initial weight, 29.5 ± 0.6 g) were fed one of the five diets for 12 weeks. The mean weight gain of fish fed the Con and TBM25 diets was significantly higher than that of fish fed the TBM100 diet (P < 0.05), but it was not significantly different from the weight gain of fish fed the TBM50 and TBM75 diets. The feed efficiency and protein efficiency ratios of fish fed the Con diet were significantly higher than those of fish fed the TBM100 diet (P < 0.05), but were not significantly different from those fed the TBM25, TBM50, and TBM75 diets. The TBM25, TBM50, TBM75, and TBM100 diets had significantly (P < 0 .05) lower incidence cost and higher profit index than the Con diet. These results suggest that the tuna by-product meal used in this study could replace up to 75% of fishmeal protein in the diet without reducing growth and feed utilization in juvenile Korean rockfish weighing 29–53 g. By considering feed cost, the TBM 75 diet is recommendable for Korean rockfish farming.

The Apparent Digestibility Coefficients of 13 Selected Animal Feedstuff for Cobia,Rachycentron canadum

AbstractThe apparent digestibility coefficients (ADCs) of crude protein, lipid, phosphorous, and amino acids, as well as energy, of 13 animal feedstuffs were determined for cobia,Rachycentron canadum(initial weight 130.0 g). The feedstuffs tested included five types of fishmeal, two of blood meal, one of poultry meat meal, two of meat‐and‐bone meal, two of feather meal, and one type of shrimp meal. A reference diet was formulated and the test diets contained 70% of the reference diet and 30% of each feedstuff. TheADCsof crude protein, lipid, energy, phosphorous, and amino acids of the test ingredients ranged from 68.97 to 92.5%, 69.3 to 95.7%, 77.5 to 98.3%, 58.2 to 80.1%, and 72.5 to 97.0%, respectively. TheADCsof crude protein of white fishmeal, steam‐dried brown fishmeal, imported flame‐dried fishmeal, spray‐dried blood cells, poultry byproduct meal, meat‐bone meal, and meat meal were significantly higher than those of dried blood meal, fermented feather meal, and hydrolyzed feather meal (P &lt; 0.05). TheADCsof lipid of dried blood meal and hydrolyzed feather meal were significantly lower than those of other feedstuffs (P &lt; 0.05). TheADCsof energy of fermented feather meal and hydrolyzed feather meal were significantly lower than those of other feedstuffs (P &lt; 0.05) and theADCsof phosphorus of white fishmeal, steam‐dried brown fishmeal, and imported flame‐dried fishmeal were significantly higher than those of the other ingredients (P &lt; 0.05).

Apparent digestibility coefficients and amino acid availability of common protein ingredients in the diets of bullfrog, Rana (Lithobates) catesbeiana

Abstract Farming of bullfrog Rana (Lithobates) catesbeiana has been expanding remarkably in the past decades to support an emerging food delicacy in southeastern China. However, lack of understanding of nutrient availability in common protein ingredients restricts precise formulation of bullfrog feeds, partially because of difficulties in collection of fecal material from bullfrog. Therefore, we carefully designed an apparatus that allows feces of bullfrogs to be collected while minimizing leaching in water and reducing stress imposed to the animals. By using this apparatus, a study was conducted to determine apparent digestibility coefficients (ADCs) of dry matter, crude protein, gross energy, and availability of phosphorus and amino acids in practical feed ingredients for bullfrog. Test ingredients included white fishmeal (WFM), brown fishmeal (BFM), porcine meat and bone meal (PMBM), poultry by-product meal (PBM), feather meal (FEM), soybean meal (SBM), peanut meal (PNM), cottonseed meal (CSM) and rapeseed meal (RSM). A reference diet and test diets that included 70% reference diet and 30% of the test feed ingredients were used with 0.5% chromic oxide included as a digestibility indicator. Bullfrogs (153 ± 3.14 g) were cultured in indoor aquaria (68 × 38 × 38 cm) equipped with the apparatus for fecal collection, and each aquarium was stocked with 15 specimens. ADCs of dry matter and energy were high (above 80%) in WFM and BFM, and low (below 40%) in CSM and RSM. ADCs of crude protein in those tested feed ingredients varied from 60.7 to 89.8%. WFM (89.8%), BFM (87.6%), SBM (83.3%), PNM (82.1%), PMBM (78.0%), PBM (77.6%) were more digestible protein feedstuffs, compared to RSM (69.5%), CSM (67.5%), and FEM (60.7%). In addition, the highest availability for phosphorus (84.8%) was observed in WFM, and the lowest value was found in FEM (63.6%). This study also demonstrated that phosphorus availability in the other seven ingredients ranged from 71.9 to 84.0%, indicating that phosphorus in BFM, PMBM, PBM, SBM, PNM, CSM and RSM could also be utilized by the bullfrog. Amino acid availability for the test ingredients followed a similar pattern to ADCs of crude protein, in which values for fishmeal were generally higher (P

Apparent digestibility coefficients of selected protein feed ingredients for loachMisgurnus anguillicaudatus

Apparent digestibility coefficients of dry matter, crude protein, lipid and energy, and amino acids availability in white fish meal, brown fish meal, meat meal, fermented soybean meal, soybean meal and rapeseed meal were determined for loach (Misgurnus anguillicaudatus) (12.05 ± 0.21 g), using a reference diet with 5 g kg−1 chromic oxide and test diets that contained 700 g kg−1 reference diet, by weight, and 300 g kg−1 of the test feed ingredients. The juvenile loach was held in 300-l tanks at a density of 30 fish per tank. White fish meal, brown fish meal, meat meal and fermented soybean meal had highest apparent digestibility coefficients (ADCs) of dry matter, crude protein and gross energy among ingredients tested, ranged from 50.4% to 60.9% for dry matter, from 64.6% to 88.4% for crude protein and from 57.9% to 79.0% for gross energy. The apparent digestibility coefficients of dry matter ranged from 61.0% to 66.9% for animal products and 50.4% to 60.7% for plant products. For crude protein, apparent digestibility coefficients of protein exceeding 80% were observed for white fish meal, brown fish meal, meat meal and fermented soybean meal, and the apparent digestibility coefficients of protein in rapeseed meal were the lowest among all the treatments. Lipids from both animal and plant feedstuffs were poorly digested by loach, ranging from 64.0% to 77.6%. The apparent digestibility coefficients of energy were similar to those of dry matter and protein, and the highest and lowest ADCs of energy were found in WFM and RM, respectively. The loach used dietary phosphorus from the animal feedstuffs more efficiently than from plant feedstuffs (soybean meal and rapeseed meal), with ADC-values ranging from 42.3% to 53.1% and from 25.1% to 32.7%, respectively. For the animal products, the availabilities of amino acids in white fish meal and brown fish meal were higher than that in meat meal, expect for Met, Asp, Pro, Gly, and Cys. Among all the plant products, the availabilities of amino acids in fermented soybean meal were higher than in soybean meal and rapeseed meal, and thus had a greater potential to be used as a dietary replacement of fish meal in loach diets.

단백질원료의 종류에 따른 황복(Takifugu obscurus) 치어의 소화율 및 성장 평가

An 8-week feeding trial was conducted to determine the apparent dry matter and protein digestibility of seven different dietary protein sources by juvenile river puffer Takifugu obscurus. Eight diets containing white fish meal (WFM), brown fish meal (BFM), squid liver powder (SLP), krill meal (KM), leather meal (LM), soybean meal (SM), or fermented soybean meal (FSM) were prepared by mixing a basal diet (BD) with one of the seven test ingredients at a ratio of 7 to 3. Fish averaging <TEX>$10.8{\pm}0.04g$</TEX> were fed the experimental diets in triplicate groups. The apparent dry matter digestibilities of BFM, WFM, FSM, SLP, LM, SM, and KM were 80, 78, 72, 67, 56, 55, and 54%, respectively, while the corresponding apparent protein digestibilities were 96, 96, 93, 92, 89, 88, and 86. The weight gain of fish fed BFM was significantly greater than that of fish fed SM or LM (P<0.05), while it was not significantly different from that of fish fed the BD, WFM, FSM, BFM, SLP, or KM. These results indicated that WFM, BFM, FSM, and SLP are potentially good protein sources for replacing fish meal in river puffer feed.

Effects of brown fish meal replacement with fermented soybean meal on growth performance, feed efficiency and enzyme activities of Chinese soft-shelled turtle, Pelodiscus sinensis

A 120-day feeding experiment was conducted to investigate the effects of partial replacement of brown fish meal (BFM) by fermented soybean meal (FSBM) in diets of Chinese soft-shelled turtle (Pelodiscus sinensis). The turtles (initial mean body weight, (115.52 ± 1.05) g) were fed with three experimental diets, in which 0%, 4.72% and 9.44% BFM protein was replaced by 0%, 3% and 6% FSBM, respectively. Results showed that the feeding rate (FR), specific growth rate (SGR) and feed efficiency ratio (FER) of turtles fed with the diet containing 3% FSBM were not significantly different from the control group (0% FSBM) (P > 0.05). However, FR, SGR and FER of turtles fed with the diet containing 6% FSBM were significantly lower than those of the control group (P 0.05). However, the uric acid concentration in turtles fed with the diet containing 3% or 6% FSBM was significantly lower than that in the control group (P 0.05). The results suggested that FSBM could replace 4.72% BFM protein in turtle diets without exerting adverse effects on turtle growth, feed utilization and measured immune parameters.

어분 종류 및 소맥분 함량이 다른 배합사료가 넙치 (Paralichthys olivaceus)의 성장과 소화율에 미치는 영향

A feeding trial was carried out to investigate the effect of different fish meal and wheat flour contents in extruded pellets on the growth and apparent nutrient digestibility of olive flounder Paralichthys olivaceus. Four extruded pellets (HB1, HB1T, HB2 and HB2T) were prepared using two kinds of high quality brown fish meal and low quality tuna fish meal. Two diets (HB1 and HB2) contained two different kinds of brown fish meal, respectively; in HB1T and HB2T, we substituted 50 % of the brown fish meal with 10 % wheat flour. Three replicate groups of fish (initial body weight of 82 g) were fed the experimental pellets to visual satiation for 15 weeks. The highest weight gain was observed in fish fed HB1, and weight gain of fish fed HB2 was significantly higher than that of fish fed HB2T (P<0.05). Feeding efficiency for fish fed HB1 was significantly higher than that of fish fed HB1T and HB2T (P<0.05), but was not significantly different from fish fed HB2. Apparent dry matter digestibility in HB1 and HB2 was significantly higher than in HB1T and HB2T (P<0.05). The highest crude protein digestibility was observed in HB1, and protein digestibility in HB1T and HB2 was higher than in HB2T (P<0.05). The results of this study suggest that fish meal quality considerably affects growth and nutrient digestibility of olive flounder fed extruded pellets, and the use of HB1 is recommended over HB1T, HB2 and HB2T for efficient olive flounder production.

Apparent digestibility of selected feed ingredients for Chinese sucker, Myxocyprinus asiaticus

Building a reliable database on apparent digestibility of protein sources is critical for accurate feed formulation and reduction of aquaculture wastes. Apparent digestibility coefficients (ADCs) of dry matter (DM), crude protein, crude lipid, gross energy, phosphorus and amino acids for white fish meal (WFM), brown fish meal (native) (BFM), fermented soybean meal (FSBM), extruded soybean meal (ESBM), soybean meal (SBM), cottonseed meal (CM) and rapeseed meal (RM) were determined for Chinese sucker ( Myxocyprinus asiaticus) (18.05 ± 0.27 g) using a reference diet (RF) and test diets (70% RF diet plus 30% of tested feedstuff) containing 0.5% chromic oxide as an inert marker. WFM had the highest apparent digestibility coefficient for DM (74.5%). For plant products, the ADCs of DM ranged from 54.3 to 71.6%. Protein digestion by Chinese sucker of WFM, BFM, FSBM and ESBM was significantly higher than CM and RM, ranging from 72.8 to 92.3% for plant products, and 90.3 to 91.2% for animal feedstuffs. Lipids from both animal and plant feedstuffs were highly digested by Chinese sucker, ranging from 89.8 to 94.9%. The highest digestibility coefficient of energy was registered for WFM, followed by BFM; and the lowest digestibility coefficient of energy was recorded for CM ( P < 0.05). The Chinese sucker did utilize dietary phosphorus from the animal feedstuffs (FSBM and ESBM) more efficiently than from plant feedstuffs (SBM, CM and RM), with values ranging from 58.8 to 61.4% and 25.8–56.0%, respectively. Amino acid availability reflected protein digestibility, except for ESBM, for which the availability of some amino acids was lower, possibly because of protein denaturation during processing. Based on the current findings, FSBM and ESBM could be considered as good potential substitutes for FM in diets for Chinese sucker.

Effects of dietary protein levels on the growth performance, digestive capacity and amino acid metabolism of juvenile Jian carp (Cyprinus carpiovar. Jian)

This experiment was conducted to evaluate the effects of protein levels on the growth performance, digestive capacity and amino acid metabolism of juvenile Jian carp. Brown fish meal was used as the sole protein source in the present study. Six isoenergetic experimental diets containing 14.4 MJ kg−1 of digestible energy and 220–495 g crude protein kg−1 diets were fed to triplicate groups of 50 fish with a mean initial weight of 16.67 ± 0.01 g for 45 days. Per cent weight gain (PWG) and feed efficiency ratio (FER) improved with an increase in the dietary protein levels up to 330 g kg−1 diet. The condition factor, relative gut length, intestinal folds height, hepatopancreas and intestine protein content improved with an increase in the protein levels up to 330–385 g kg−1 diet. Trypsin, creatinkinase, Na+, K+-ATPase and alkaline phosphatase activities generally followed the same tendency as that of growth parameters. Amylase and γ-glutamyl transpeptidase (γ-GT) activities were negatively correlated with increasing protein levels from 220 to 330 g kg−1 diet, and no differences were found thereafter. Lipase activity was unaffected by protein levels. Lactobacillus amount was increased with protein levels up to 275 g kg−1 diet, while Aeromonas amount followed the opposite pattern. Escherichia coli amount was not influenced by dietary protein levels. Glutamate–oxaloacetate transaminase (GOT) activities in the hepatopancreas and plasma ammonia concentration (PAC) were not influenced by protein levels between 220 and 275 g kg−1 diet, but significantly increased with increasing protein levels from 275 to 440 g kg−1 diet, and remained similar thereafter. Glutamate–pyruvate transaminase (GPT) activities significantly increased with protein levels >275 g kg−1 diet. Based on the broken-line model, the dietary protein requirement for PWG of Jian carp (16.7–55.0 g) was estimated to be 341 g kg−1 diet with a digestible energy of 14.4 MJ kg−1 diet.

Apparent Digestibility Coefficients of Selected Feed Ingredients for Yellowfin Seabream, Sparus latus

Abstract The apparent digestibility coefficients (ADC) of dry matter (DM), crude protein (CP), gross energy (GE), and amino acid in seven feed ingredients were determined with juvenile yellowfin seabream (initial body weight, 41 ± 2 g; means ± SD) through two digestibility trials. The ingredients consisted of white fish meal (WFM), Peruvian fish meal (PFM), brown fish meal (BFM), rapeseed meal (RM), soybean meal (SBM), extruded soybean meal (extruded SBM), and peanut meal (PM). In each of the two trials, a casein–gelatin reference diet was mixed with test ingredients in a ratio of 70:30 to produce a series of diets, and yttrium oxide was used as the inert marker. The reference and test diets were fed to yellowfin seabream reared at 27.5 ± 1 C, and fecal samples were collected by siphoning. The derived DM, CP, and GE ADCs (means ± SD) for the test ingredients were, respectively, WFM – 72.3 ± 3.87, 86.4 ± 1.06, and 93.6 ± 2.63; PFM – 54.1 ± 15.45, 80.5 ± 7.81, and 77.4 ± 11.9; BFM – 57.7 ± 2.34, 82.8 ± 3.07, and 84.5 ± 5.77; RM – 33.5 ± 5.50, 84.7 ± 2.83, and 56.3 ± 9.87; SBM – 58.7 ± 4.42, 92.6 ± 3.94, and 58.1 ± 2.91; extruded SBM – 65.1 ± 16.52, 89.7 ± 1.68, and 64.8 ± 6.23; and PM – 70.6 ± 1.43, 97.3 ± 3.52, and 59.8 ± 4.78. The ADC of CP of both plant and animal feed ingredients was high, whereas DM and GE values varied greatly. Apparent DM digestibility coefficients of ingredients decreased as ash or fiber contents of ingredients increased, and the variation of apparent GE digestibility coefficients of ingredients is similar to that in DM, with the exception of the value for PM.

Apparent Digestibility Coefficients of Various Feed Ingredients for Grouper Epinephelus coioides

Apparent digestibility coefficients (ADC) of dry matter, crude protein, lipid, gross energy, amino acids, and fatty acids in white fish meal, brown fish meal, soybean meal, peanut meal, and yeast were determined for grouper Epinephelus coioides. Apparent digestibility was determined using a reference diet with 0.5% chromic oxide indicator and test diets that contained 70% reference diet and 30% of the feed ingredient being evaluated. The fish, averaging 12.0 g, were held in 250-L tanks at a density of 30 fish per tank. Feces were collected from three replicate groups-of fish. Apparent dry matter digestibility of ingredients was 78.85 ± 2.43, 79.11 ± 0.61, 69.85 ± 3.60, 73.67 ± 2.30 and 57.70 ± 4.69% for white fish meal, brown fish meal, soybean meal, peanut meal, and yeast, respectively. Apparent gross energy digestibility of ingredients was 93.27 ± 2.90, 89.48 ± 1.78, 70.52 ± 4.01, 73.13 ± 2.41 and 51.67 ± 2.01% for white fish meal, brown fish meal, soybean meal, peanut meal, and yeast, respectively. Apparent protein digestibility of ingredients was 89.82 ± 1.24, 87.34 ± 1.25, 83.97 ± 1.92, 80.79 ± 1.95, and 61.14 ± 0.54% for white fish meal, brown fish meal, soybean meal, peanut meal, and yeast, respectively. White fish meal and brown fish meal showed higher protein digestibility among ingredients tested (P ± 0.01). Lipid digestibility of ingredients was high (90.66-94.48%) and not significantly different except for yeast. Amino acid availability values for test ingredients were similar to values of protein digestibility. Amino acid availability values of white fish meal and brown fish meal were higher than other ingredients. Fatty acid availability values for test ingredients were similar to values of lipid digestibility. In general, the digestibility of most fatty acids was over 80% in all ingredients, except for 14:0 in yeast and 18:0 in peanut meal, PUFA + HUFA > MUFA > SFA. Longer-chain saturated fatty acids were less digestibility, except for 14:0, with digestibilities diminishing as fatty acid chain length increased. Apparent digestibility of dry matter, crude protein, lipid, gross energy, amino acids, and fatty acids in yeast was the lowest among the ingredients.

Substituting fish meal with soybean meal in diets of juvenile cobia Rachycentron canadum

An 8-week feeding trial was conducted with cobia to determine the amount of soybean meal that could replace fish meal in formulated diets without reducing growth. Juvenile cobia (initial mean weight, 32 g) were fed 48% crude protein diets in which dietary protein was supplied by brown fish meal or a mixture of hexane extracted soybean meal and the fish meal, resulting in 10%, 20%, 30%, 40%, 50% and 60% of fish meal protein being replaced by soybean protein. The fish readily accepted all seven experimental diets and no fish died during the trial. Detrimental effects on growth performance were obvious when half of the fish meal protein was replaced by soybean protein. There existed a significant difference in fish weight gain, feed conversion ratio (FCR), protein efficiency ratio (PER) and net protein utilization (NPU) when the replacement level for fish meal protein was increased from 40% to 50%, indicating that up to 40% of fish meal protein can be replaced by soybean meal protein without causing reduction in growth and protein utilization. On the other hand, quadratic regression analysis shows a growth optimum at 16.9% replacement of fish meal protein by soybean meal protein. Lipid concentrations in the cobia muscle increased significantly as dietary soybean meal increased. Muscle concentrations of free threonine and histidine decreased as use of the soybean meal increased in the diets. Since methionine concentration in the test diets decreased from 2.52 to 1.36 g 16 g −1 N as the soybean meal protein replacement level was increased from 0% to 60% while all other essential amino acids remained relatively constant, dietary requirement of methionine was calculated assuming it was equally available between the two proteins. The broken-line model analysis based on fish weight gain shows a breakpoint when dietary methionine+cystine concentration was 2.66 g 16 g −1 N or 1.28 g 100 g −1 diet.

Dietary amino acid profiles and growth performance in juvenile kuruma prawn Marsupenaeus japonicus

To assess the reference dietary amino acid profiles for juvenile kuruma prawn Marsupenaeus japonicus a feeding trial was conducted using six semi-purified diets containing casein-gelatin and pre-coated supplemental crystalline amino acids (CAA) and a control diet containing intact protein (casein-gelatin). Pre-coated CAA were supplemented to the diets to simulate dietary amino acid profiles to those of the prawn egg protein (PEP), prawn larvae whole body protein (PLP), prawn juvenile whole body protein (PJP), squid meal protein (SMP), short-necked clam protein (SNP) and brown fish meal protein (BFP). The result showed that kuruma prawn juveniles are capable of utilizing the pre-coated CAA and higher growth performances were observed in the groups fed the PJP, SMP and the control diets than those fed the PLP, SNP, BFP and PEP diets. The essential amino acid proportions (A/E ratios) of the whole body of kuruma prawn differ slightly when compared with the other penaeids or freshwater prawn. The results suggest that PJP and SMP would be suitable as a reference dietary amino acid profile for juvenile prawn.

Effect of fish size and temperature on the utilization of different protein sources in two catfish species

Two sets of feeding trial were conducted to determine the effect of size and temperature on the utilization of different protein sources in two catfish species. In both the experiments, the fish were fed to apparent satiation daily at 08.00 and 18.00 hours, and faecal matter collected through slow siphoning. The first experiment was designed to study the effect of fish size on apparent digestibility coefficients for plant and animal proteins in the African catfish, Clarias gariepinus (Burchell, 1822). Three size classes (105–109 g; 780–830 g; 1250– 1300 g) of fish were stocked in triplicate sets of 600-L plastic pools fitted with a flow-through system (2 L min−1). Within each size class, the apparent digestibility coefficient (ADC) for protein varied significantly with the source and quality of protein used. Soybean meal and fishmeal protein were utilized with greater efficiency, whereas rice bran protein was least digestible. An increase in ADC protein was apparent with increase in fish size for high protein sources such as soybean meal, full-fat soybean, laboratory-prepared fishmeal, steam-cooked brown fishmeal and dried fish. ADC protein for other ingredients decreased with increase in size. In the second experiment, the influence of varying temperature on ADC for protein was determined in the catfish, Heteropneustes fossilis (Bloch) (6–8 g). Triplicate groups of 25 fish were kept at three different ambient temperatures (18, 28 and 38 °C), in 70-L polyvinyl indoor flow-through (1–1.5 L min−1) circular tanks (water volume = 55 L). The trend in utilization of protein from different sources remained similar at the three temperatures. For each ingredient, digestibility values obtained at 18 °C were significantly lower than those obtained at 28 °C and 38 °C. Optimal protein utilization in H. fossilis was measured at 28 °C.

Influence of different dietary amino acid patterns on growth and body composition of juvenile Japanese flounder, Paralichthys olivaceus

A feeding trial using five semi-purified diets (50% crude protein) was conducted to investigate the effects of different dietary amino acid patterns on growth and body composition of juvenile Japanese flounder. The control diet contained casein and gelatin as intact protein sources and four other diets contained 30% casein–gelatin (2:1, w/w) and 20% crystalline amino acids (CAA). CAA were added to the diets to simulate the amino acid pattern found in red sea bream egg protein (REP), Japanese flounder larvae whole body protein (FLP), Japanese flounder juvenile whole body protein (FJP), and brown fish meal protein (BFP), respectively. The test diets were fed to triplicate groups of juveniles (2.75±0.05 g) twice a day for 40 days to evaluate weight gain, survival, feed conversion efficiency (FCE), protein efficiency ratio (PER), and apparent protein utilization (APU). The apparent retention of total dietary amino acids in the whole body and A/E ratios of the whole body were also evaluated. The highest weight gain was observed in fish fed the diet containing the dietary amino acid pattern of BFP followed by fish fed the control, FJP, FLP and the REP diets. Percent survival, FCE, PER and APU were also significantly ( P<0.05) affected by the amino acid pattern in the diets, indicating the highest value in fish fed the BFP diet. Except for a few amino acids, the amino acid composition of the whole body did not show marked differences with different dietary amino acid pattern. Results suggest that BFP could be more suitable as a reference amino acid pattern in the diet of juvenile Japanese flounder compared to the amino acid pattern of FLP, FJP or REP.

Effect of lysine and methionine supplementation to a soy protein concentrate diet for red sea bream Pagrus major

: The supplemental effect of amino acids (AAs) to a soy protein concentrate (SPC) diet for red sea bream Pagrus major was evaluated for different-sized fish. The fish were fed artificial diets based on 52% SPC for 60 days in juvenile (mean weight 11.7 g) and for 153 days in yearling (mean weight 178 g). To these diets L-lysine hydrochloric acid (LS), DL-methionine (MS) and both L-lysine and DL-methionine (LMS) were supplemented. A control diet without AA supplementation (NOS) and a reference diet based on brown fish meal (BFM) were also tested. In the juvenile fish, the growth performance of the MS group was significantly higher than the NOS group. The growth performance was further improved by the dietary supplementation of both Lys and Met (LMS group). Lenticular opacity was not observed in these two dietary groups. On the other hand, the growth performance of the NOS and LS groups was lowest, and the incidence of lenticular opacity of the LS group was higher rather than the NOS group. In the yearling fish, feed conversion of the LMS group was slightly higher than the NOS group, but the growth performance of the LMS group was similar to the NOS group. These parameters were similar or slightly lower in the LS or MS groups compared with the NOS group. Lenticular opacity was not observed in any dietary groups for yearling fish. In both juvenile and yearling fish, the performances of the BFM groups were superior to the other dietary groups. The results for juvenile fish indicate that the quality of the SPC diet is improved by the Met supplementation, and further improved by both Lys and Met supplementation. Furthermore, the results in the present study suggest that the AA requirement of red sea bream changes with growth and/or age.

The effect of additional arginine in the high defatted soybean meal diet on the growth of giant gouramy Osphronemus gouramy Lac.

SUMMARY: Four experimental diets were used to determine the effect of additional arginine in the high defatted soybean meal (DSM) diet on the protein retention and the growth of giant gouramy, Osphronemus gouramy Lac. Diet A contained 50% of the protein from brown fish meal (BFM) and 50% from DSM; diet B contained 50% BFM and 50% DSM plus 0.70% arginine; diet C contained 25% BFM and 75% DSM and diet D contained 25% BFM and 75% DSM plus 0.60% arginine. Fish, with mean bodyweight of 21.6 ± 1.13 g, were fed on the experimental diets for 56 days. The DSM diet (diet C) produced lower protein retention (PR), lipid retention (LR), feed efficiency (FE) and daily growth rate (DGR) than diet A (50% BFM + 50% DSM). The addition of arginine in diet D (75% DSM in dietary protein) can improve the DSM quality, which was shown by producing the same PR, LR, FE, and DGR as in diet A. These results indicated that arginine is one of the important essential amino acids for the high defatted soybean meal diet of giant gouramy.