Fish Meal Replacement Level Research Articles

Effects of fish meal replacement by meat and bone meal supplemented with garlic (Allium sativum) powder on biological indices, feeding, muscle composition, fatty acid and amino acid profiles of whiteleg shrimp (Litopenaeus vannamei)

Shortage of fish meal (FM) resources in the marine environment, high price and high demand for this ingredient led researchers to seek for alternative protein resources such as meat and bone meal (MBM). The effects of adding MBM and garlic powder to the shrimp diet on growth performance, muscle composition, amino acid and fatty acid profiles of whiteleg shrimp (5.00 ± 0.23 g) were investigated. A total of six dietary treatments were formulated: 0%MBM (control without garlic powder), 25%MBM and 50%MBM (treatments without garlic powder; WG treatments); 0%MBM+G (control with garlic powder), 25%MBM+G and 50%MBM+G (treatments with garlic powder; G treatments). Our results indicated that increase MBM level in the diets (up to 50%MBM) impaired growth performance, muscle composition, fatty acid and amino acid profiles in the muscle of shrimp. Interestingly, garlic supplementation improved the aforementioned factors so that shrimp fed 50%MBM+G diet had no significant difference when compared to 0%MBM group. The current results indicated that garlic could increase levels of FM replacement by increasing feed intake, improving protein and amino acid utilization. Overall, 50%MBM+G diet is recommended for use in shrimp production.

Success of fishmeal replacement through poultry by‐product meal in aquaculture feed formulations: a meta‐analysis

AbstractPoultry by‐product meal (PBM) is a popular animal‐based protein source tested in aquaculture feed formulations for replacing fishmeal (FM), mainly due to its high protein content, relatively cheap price and broad availability. However, due to the well‐documented variability in success of PBM inclusions, a meta‐analysis approach was utilized to summarize the efficacy and success of PBM inclusion in aquaculture diet formulations substituting FM. Hedges’g effect sizes were calculated by quantitatively comparing final weight and feed conversion ratio (FCR) between animals fed control (100% FM) and PBM‐supplemented FM diets using data from 47 published articles targeting 33 different species (141 and 96 effect size calculations for final weight and FCR, respectively). In addition, several analyses were performed to determine the effect of different moderators as well as variation across species. Meta‐regression was conducted to evaluate the effect of varying PBM proportions of the diet on the response variables. Overall, a non‐significant final weight but a significant higher FCR was detected with aquaculture species fed PBM diets. Similar trends in final weight were observed for subgroups. However, FCR for crustaceans and marine fish fed PBM diets was not significantly different than those fed control diets. In both freshwater and marine fish, ‘species’ was a significant moderator effect on responses, while the ‘level of FM replacement’ was significant only in marine fish. Higher between‐study heterogeneity was detected for fish, which may be due to the influence of certain factors, such as variability in nutritional quality and palatability and digestibility of PBM or due to variability on the fish meal used. In contrast, low between‐study variation was observed in crustaceans indicating consistent success in PBM‐supplemented diets for shrimp compared with fish.

The effect of partial replacement of fish meal by soy protein concentrate on growth performance, immune responses, gut morphology and intestinal inflammation for juvenile hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂)

An 8-week feeding trial was conducted to investigate the effects of partial replacement of fish meal by soy protein concentrate (SPC) on the growth performance, immune responses, intestine morphology and relation gene expression of intestinal inflammation for juvenile hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂) (initial weight 12.5 ± 0.00 g). Eight isonitrogenous and isolipidic diets (48.61% protein and 11.17% lipid) were formulated by replacing 0% (the control), 11%, 22%, 33%, 44%, 55%, 66%, and 77% of fish meal (FM) with SPC, respectively (the eight dietary be named FM, S11, S22, S33, S44, S55, S66, and S77, respectively). With the replacement level increased, the final body weight, weight gain ratio (WGR), specific growth rate (SGR), and survival rate of fish were significantly decreased (P < 0.05) compared with the group FM. By contrast, the feed conversion ratio (FCR) of fish was significantly increased (P < 0.05) when the replacement level up to 44%. Partial FM replacement by SPC (ranging from 11% to 77%) substantially reduced (P < 0.05) the serum total protein, albumin, and total cholesterol contents compared with the group FM. Liver total superoxide dismutase, glutathione peroxidase, catalase activities, and total antioxidant capacity showed the same trend of gradual increase first and then decrease. Their highest values were found in the replacement levels of 55%, 33%, 22%, and 55% and were significantly higher (P < 0.05) than the control group. The lowest malondialdehyde content was observed in group S77 and was significantly lower (P < 0.05) than that of the control group. The complements C3 and C4 contents of fish fed with experimental diets (replacement level ranged from 11% to 66%) were significantly higher (P < 0.05) than the group FM. The liver lysozyme activity of the control group was the lowest and was significantly lower than that of other dietary treatments (P < 0.05). Villus length and muscle thickness in the intestine of fish were significantly lower (P < 0.05) than other groups when the replacement level exceeded 44%. With dietary replacement levels increased, the TLR22, MyD88, p65, pro-inflammatory cytokines (IL-1β, TNF-α, IL-12P40 and INF-γ) and anti-inflammatory cytokines (TGF-β, IL-10, epinecidin, MHCIIβ and hepcidin) mRNA levels in the proximal intestine were significantly up-regulated (P < 0.05). The TLR22, MyD88, p65, pro-inflammatory cytokines (IL-1β, TNF-α, IL-12P40 and INF-γ) and anti-inflammatory cytokines (TGF-β, IL-10, MHCIIβ and hepcidin) mRNA levels in the mid intestine were significantly up-regulated (P < 0.05). The mRNA levels of TLR22, anti-inflammatory cytokines (IL-1β, TNF-α, IL-12P40, INF-γ) and anti-inflammatory cytokines (TGF-β, IL-10, epinecidin, MHCIIβ and hepcidin) in the distal intestine were significantly down-regulated (P < 0.05). The mRNA expression of MyD88 and p65 mRNA were showed a tend increased first and then decreased, and the highest values were observed in group S33 and S55 (P < 0.05), respectively. Based on the present work, the correlation between WGR and FM replacement level with SPC was described using the broken-line model, which estimated the optimum FM replacement to 37.23% for juvenile hybrid grouper dietary.

Fermented mulberry leaf meal as fishmeal replacer in the formulation of feed for carp Labeo rohita and catfish Heteropneustes fossilis-optimization by mathematical programming.

Search for cost-effective, eco-friendly and sustainable plant resources as potential feedstuff to replace fishmeal in the formulation of feed for fish has been in the forefront of aquaculture researches since the last few years. In this study, experiments were conducted to evaluate if replacement of fishmeal by the fermented leaf meal of mulberry (Morus indica) was viable in the formulation of feed for carp fish Labeo rohita and catfish Heteropneustes fossilis. Four iso-proteinous, iso-lipidic and iso-energetic experimental feed were formulated by replacing 0, 25, 50 and 75% of fishmeal by the fermented mulberry leaf meal (FMLM), and both species were grown on these feeds for 8weeks. Since the results revealed differences in response to fishmeal replacement level between parameters, we determined optimum fishmeal replacement level (OFRL) for each parameter from the polynomial curve equation. While maximum weight gain and specific growth rate and minimum feed conversion ratio was found at 30-32% OFRL for L. rohita and at 52-53% OFRL for H. fossilis, other parameters responded differently in both fish. Therefore, we applied a two-phase fuzzy goal programming technique using all parameters, which showed overall OFRL for L. rohita and H. fossilis as 30.95% and 52%, respectively. We also applied the concept of 'decision tree' to identify the key factor behind utilization of FMLM. It was concluded that activity of amylase and subsequent utilization of carbohydrate was the key factor in utilizing FMLM. Interestingly, H. fossilis was found more efficient in utilizing carbohydrate of FMLM than L. rohita.

Potential of poultry by-product meal as a main protein source in diets formulated for juvenile sobaity (Sparidentex hasta)

60-day feeding trial was conducted to evaluate the potential of using poultry by-product meal (PBM) as partial replacement of fish meal (FM) in the diets for juvenile sobaity. Six iso-nitrogenous and iso-lipidic diets were formulated to contain graded levels of PBM, at 0 (as control diet), 15, 25, 35, 45, and 55% of FM replacement. Each diet was fed to groups of 20 juvenile sobaity in triplicate 300-l tanks, thrice a day to apparent satiation. Survival, feed conversion ratio and efficiency ratio showed that there were no significant differences between fish fed PBM based diets compared to fish fed the reference diet. Growth performance and protein efficiency ratio of fish fed the PBM15 and 25 was higher than other treatments. The somatic indices, biochemical content of whole body and fillet, hematological factors were not significantly affected by the replacement level of FM with PBM, with the exception of serum cholesterol and triglyceride content. The results of the present study indicated that PBM is a suitable replacement for fish meal in juvenile sobaity diet up to 55% substitution.

Nutritional evaluation of a short-horned grasshopper\u201a Oxya hyla hyla (Serville) meal as a substitute of fishmeal in the compound diets of rohu, Labeo rohita (Hamilton)

BackgroundAqua feed demand is rising with the growth of intensive aquaculture. Fishmeal is the major conventional protein source of fish feed but its production cannot be increased due to resource limitation. Thus, suitable fishmeal (FM) substitute is a need to sustain the growth of aquaculture. Use of edible insects in animal and fish feed is gaining interest. Grasshoppers are edible insect and contain considerably high percentage of crude proteins and other nutrients. In the present study, the nutritional efficiency of Oxya hyla hyla meal as replacer of FM was evaluated by feeding Labeo rohita fingerlings with seven iso-nitrogenous compounded diets (33% crude protein) where FM was substituted by Oxya meal (OM) at 0%, 17%, 33%, 50%, 67%, 83% and 100% levels in diet 1 (D1) to diet 7 (D7) respectively. Feeding trail was continued for 100 days.ResultsFeeding experiments showed that OM-incorporated diets were acceptable to the fish and feeding on the diets they grew significantly after 100 days feeding trial in wet weight and length. Results revealed that up to 50% replacement of FM (up to diet 4) did not affect the growth performances, condition factor of fish, apparent protein digestibility, nitrogen metabolism, food conversion ratio (FCR) and protein efficiency ratio (PER) with respect to reference diet (D1, without OM). FCR and PER were found inferior in the diets D5, D6 and D7 where more than 50% FM was replaced. Moreover, diets regardless of FM replacement level showed no negative impact on hepato-somatic index, digesto-somatic index, relative length of gut, retention of protein, lipid and ash and on carcass compositions of the fish.ConclusionThe results revealed that the grasshopper species, O. hyla hyla, might be a new protein-rich ingredient for aqua feed formulation and up to 50% replacement of FM by OM did not affect the growth performances, feed utilisation parameters and flesh quality of the fish L. rohita fingerlings. Therefore, this study suggested that OM meal could be incorporated at least as partial substitute of FM in the compounded carp diet.

Litopenaeus vannamei fed diets with different replacement levels of fish meal by fish silage: A molecular approach on intestinal microbiota

We investigated the intestinal microbiota in shrimp fed diets with five replacement levels (0, 25%, 50%, 75% and 100%) of fish meal by fish silage. An 8-week feeding trail was conducted in 15 fibreglass tanks (400 L volume, three replications for each diet) with 50 shrimps (initial weight 0.26 +/- 0.03 g) per tank. After 8-week trial, shrimp fed diets with low replacement levels (0% and 25%) of fish meal by fish silage had significantly enhanced growth performance (p 0.05), which indicated the limited impact of dietary fish silage on intestinal microbiota.

Optimum fish meal replacement by soy protein concentrate from soymilk and phytase supplementation in diet of red sea bream, Pagrus major

Two trials were carried out to determine the optimal replacement level of fish meal (FM) by soy protein concentrate (SPC) derived from soymilk without supplementation of indispensable amino acids (IAAs) or palatability enhancers and whether phytase supplementation can help to replace more SPC in diet of juvenile red sea bream, Pagrus major. In Trial 1, five isoenergetic diets were formulated: 67% FM as protein source in the control diet (C), and FM was replaced by 60 (SPC60), 70 (SPC70), 80 (SPC80) and 100% (SPC100) by SPC. In Trial 2, diets C and SPC80 were the same as in Trial 1, and phytase was supplemented in SPC80 at 1000 (P1), 2000 (P2), 3000 (P3) and 4000 (P4) FTU/kg diet. Thirty (ca. 23 g) and 20 fish (ca. 21 g) were randomly distributed into each fifteen and eighteen 300 L indoor tanks in Trial 1 and 2, respectively. Fish in both trials were fed two times daily until apparent satiation for 10 weeks. At the end of both trials, feces were collected after feeding with chromic oxide (Cr2O3) mixed diets. In Trial 1, there were no significant differences in final mean weight, specific growth rate (SGR), daily feeding rate (DFR), feed efficiency (FE), condition factor (CF), and retention efficiency of protein, lipid and energy until 70% (SPC70) FM replacement by SPC (P > .05). However, 80% FM replacement significantly reduced final mean weight, FE and lipid retention efficiency compared with group C (P < .05). There were no significant differences in plasma constituents, except total cholesterol level. In Trial 2, phytase was supplemented in SPC80 to determine whether it helps to stimulate growth up to the level of the control group. Fish fed SPC80 once again displayed significantly lower final mean weight, SGR, FE, phosphorus (P) digestibility, and retention efficiency of protein, lipid, energy and P compared with control group (P > .05). Final mean weight, FE, P digestibility, and retention efficiency of protein, lipid and P were significantly improved in fish fed diet P2 (phytase at 2000 FTU/kg diet) compared with those fed diet SPC80. However, phytase supplementation did not stimulate the growth up to the level of group C. The results demonstrated in juvenile red sea bream that 70% of FM can be replaced by SPC derived from soymilk without supplementation of IAAs and palatability enhancers.

Replacement of fishmeal by fermented soybean meal could enhance the growth performance but not significantly influence the intestinal microbiota of white shrimp Litopenaeus vannamei

Intestinal microbiota plays a vital role in nutrient metabolism, pathogen resistance and development of immune system. Here, an Illumina-based method was employed to investigate the intestinal microbiota in white shrimp fed diets with five replacement levels (0, 10, 20, 30 and 40%) of fishmeal by fermented soybean meal (FSM). The results of growth trail revealed that shrimp fed a diet with 20% replacement of fishmeal by FSM (FSM20) had significantly better growth performance. Based on the sequence analysis, we got a total of 2535 OTUs from all of samples. These OTUs were identified into 22 phyla, among which Proteobacteria was the most abundant one. The richness and diversity of intestinal microbiota were not changed by dietary different levels of FSM (P > .05). Results of functional prediction showed that membrane transport was the most abundant function matching in KEGG database at level 2. In terms of nutrition-related metabolism functions, there was no significant difference in all of dietary groups (P > .05). All the results above showed that dietary appropriate level of FSM (20%) could enhance the growth performance, but not affect intestinal microbiota of shrimp.

Effect of dietary fermented soybean meal on growth, intestinal morphology and microbiota in juvenile large yellow croaker, Larimichthys crocea

An 8-week feeding trial was conducted to evaluate the effect of replacement of fish meal (FM) with fermented soybean meal (FSM) on growth performance, intestinal morphology and microbiota of juvenile large yellow croaker (Larimichthys crocea). Replacement ratio of FM with FSM were 0%, 15%, 30%, 45%, 60% and 75%, respectively (marked as FSM0, FSM15, FSM30, FSM45, FSM60 and FSM75). The results indicated that the survival ranged from 84.78% to 99.44%, and no significant differences were observed among all treatments (p > 0.05). Weight gain ratio (WGR) and specific growth rate (SGR) significantly decreased when the replacement level of FM protein exceeded 60%, and fish fed the FSM60 and FSM75 diets had lower WGR and SGR than those fed the other diets. Feed intake (FI) and feed conversion rate (FCR) significantly increased with replacement levels of FM increasing. Illumina high-throughput sequence analyses showed that the alpha diversity did not differ among the diets of FSM0, FSM15 and FSM75. The whole community of tested samples was not modified by FSM, Firmicutes and Proteobacteria were the dominant flora in the intestines based on the phyla level. The dominant phyla in the water sample were Proteobacteria, Bacteroidetes. Fish fed the diet containing FSM75 significantly reduced the species abundance of Paenibacillus. There was a certain correlation between the intestine microbiota and SGR, antioxidant, and immune. Results indicated that up to 45% of FM can be replaced by FSM without negative effects on growth performance and intestinal integrity of juvenile large yellow croaker.

Fermented Soybean Meal as a Protein Source in Diets for Yellow Perch (Perca flavescens)

A feeding trial was performed to investigate fermented soybean meal as a direct fishmeal replacement in juvenile Yellow Perch Perca flavescens diets. Four fishmeal replacement levels (25, 50, 75 and 100%) using fermented soybean meal were compared with a fishmeal control diet. Survival, weight gain, food conversion, protein efficiency, viscerosomatic index, hepatosomatic index, Fulton-type condition, and muscle ratio were determined after 105 days. No mortalities were observed during the feeding trial. Weight gain and feed conversion ratio were significantly impacted and negatively correlated with increasing fermented soybean meal inclusion. Fish fed diets containing 75% or greater fermented soybean meal failed to reach 100% weight gain by conclusion of the trial. Hepatosomatic index and viscerosomatic index showed no impact by replacement of fishmeal. Fermented soybean meal as a direct replacement for fishmeal does not appear to be a suitable replacement.

Effects of replacing fish meal with soybean meal on growth performance, feed utilization and physiological status of juvenile obscure puffer, Takifugu obscurus

An 8-week feeding trial was conducted to evaluate the growth performance, feed utilization and physiological status of obscure puffer, Takifugu obscurus (13.03 ± 0.14 g) fed diets in which fish meal (FM) was replaced with various levels of dehulled and defatted soybean meal (SBM): 0% (SBM0), 15% (SBM15), 30% (SBM30), 45% (SBM45), 60% (SBM60) and 75% (SBM75). No significant differences were observed in weight gain and specific growth rate (SGR) of fish when FM replacement level was lower than 30%, and the broken-line model of SGR showed the maximum replacement level was 40%. Fish fed the SBM-containing diets had a lower red blood cell value compared to the control. The hemoglobin and methemoglobin values showed a declining tendency as dietary SBM level increased. Plasma triacylglycerol, cholesterol and low-density lipoprotein cholesterol levels also showed a decreasing trend that was associated with the reduced crude lipid content of whole body as dietary SBM level increased. The activities of alanine aminotransferase and aspartate aminotransferase in fish fed the SBM-containing diets were all higher than those fed the control diet while glutathione peroxidase and catalase activities were lower than the control group. Results indicated that up to 40% FM protein, based on the broken-line analysis of SGR, can be replaced with SBM in diet for obscure puffer juveniles with supplemental lysine, methionine and taurine.

Replacement of fish meal with Bacillus pumillus SE5 and Pseudozyma aphidis ZR1 fermented soybean meal in diets for Japanese seabass (Lateolabrax japonicus)

This study examined the effects of replacing fish meal (FM) with three different types of soybean meal (SM) including untreated SM, Bacillus pumillus SE5 (BP) fermented SM (BPFSM) and Pseudozyma aphidis ZR1 (PA) fermented SM (PAFSM) in diets for Japanese seabass (Lateolabrax japonicus). A basal diet was formulated using FM (FM diet), and six other diets were produced by substituting 40 or 80% of FM with SM, BPFSM or PAFSM (SM40, SM80, BPFSM40, BPFSM80, PAFSM40 and PAFSM80 diets). Each diet was fed to triplicate groups of fish (7.14 ± 0.05 g) twice daily for eight weeks. Replacing 40% of FM with SM sources did not significantly influence growth (P > 0.05), while increasing the substitution level to 80% led to reduced growth rates (P < 0.05). The groups received SM80 and PAFSM80 diets showed significantly higher feed conversion ratio and lower protein digestibility than FM group. Furthermore, notably lower dry matter digestibility was detected in SM80 group. Remarkably lower serum total antioxidant capacity was found in the SM80 group, and catalase activity did not significantly differ between FM and BPFSM40 groups. Serum malondialdehyde concentration was enhanced by increasing FM replacement level and the highest value was observed in the SM80 fed fish. FM and PAFSM40 groups showed significantly higher lysozyme activity than the SM80 group. Fish fed the BPFSM40 diet exhibited the highest complement C3 activity and the lowest value was observed in the SM80 group. Expression of lysozyme gene in spleen was down-regulated in the SM80 group, and no significant difference in expression of C3 gene was found among FM, BPFSM40 and PAFSM40 groups. Digestive enzymes activity and gut morphology were significantly influenced by FM replacement. Expression of HSP70 and pro-inflammatory genes including TNF-α and IL-1β were up-regulated by FM replacement and relatively lower expression levels were found by using fermented SM. An opposite trend was observed for the anti-inflammatory TGF-β gene expression. Serum d-lactate concentration was significantly increased by replacing 80% of FM with any of the SM sources. These findings indicated that using fermented SM, particularly BPFSM, beneficially influences feed utilization, antioxidant capacity, innate immunity and gut health in juvenile Japanese seabass.

Substituting fish meal with housefly (Musca domestica) maggot meal in diets for bullfrog Rana (Lithobates) catesbeiana: Effects on growth, digestive enzymes activity, antioxidant capacity and gut health

An 8-week feeding trial was carried out to evaluate the effects of replacing fish meal (FM) with housefly (Musca domestica) maggot meal (HFMM) on growth, antioxidant capacity, digestive enzymes activity, and gut health of bullfrog Rana (Lithobates) catesbeiana. A basal experimental diet was formulated using FM and soybean meal as the major protein sources, then four other diets were produced by replacing 25, 50, 75 or 100% of FM with HFMM (FM, HFMM25, HFMM50, HFMM75 and HFMM100 diets). Each diet was fed to triplicate groups of bullfrog (34.1 ± 1.10 g) to apparent satiation twice daily. No significant linear or quadratic trends were observed between FM replacement level and growth, feed utilization and survival rate (P > 0.05). A significant negative linear trend was detected between the incremental levels of HFMM and apparent digestibility coefficients (ADCs) of dry matter, protein and lipid, while positive linear and quadratic trends were found in ADC of phosphorous (P < 0.05). A negative linear trend was observed between whole-body ash content and HFMM level. Positive linear and quadratic trends were found between serum aspartate aminotransferase, alkaline phosphatase and lysozyme activities and incremental HFMM levels. Liver superoxide dismutase and catalase activities were increased linearly, and total antioxidant capacity was enhanced both linearly and quadratically by incremental levels of HFMM. In contrast, a negative linear trend was found in liver malondialdehyde concentration. A significant positive quadratic trend was found between intestinal protease, lipase and amylase activities and incremental levels of HFMM. Histological observations revealed a significant negative linear trend between HFMM level and villus height and muscular thickness. Gut microbiota analysis showed no significant changes in the operational taxonomic unit (OTU) diversity and richness indices among treatments. Positive linear and quadratic trends were found between incremental HFMM levels and expression of liver HSP70 and IGF-Ι and intestinal TNF-α, IL-1ß, IL-8 and IL-17 genes. The findings in this study showed that although growth performance was not significantly affected by total replacement of FM with HFMM, nutrients digestibility and gut health could be adversely influenced at higher replacement levels.

Growth Performance and Feed Utilization of Low-Cost Artificial Feeds for Juvenile Asian Horseshoe Crab Culture

ABSTRACT A feeding experiment was undertaken for 84 days to investigate the growth performance and the feed utilization of two horseshoe crab species from partial replacement of fish meal (FM) with blood meal (BM), meat and bone meal (MBM), and poultry by-product meal (PBM) in their diet. Triplicate groups of Tachypleus tridentatus or Carcinoscorpius rotundicauda were fed nine isonitrogenous (digestible protein 40%) and isoenergetic (digestible energy 14 MJ kg-1) diet treatments. For both species, the growth performance, that is, final individual body weight and thermal-unit growth coefficient (TGC), and feed utilization, that is, including feeding rate (FR) and feeding efficiency ratio, of the juveniles fed with PBM and MBM at 2:1 ratio were higher than those of juveniles fed with diets containing PBM and MBM at 1:1 ratio at the same FM replacement level. Final individual body weight, TGC, and FR of the two species fed with the 100% FM replacement diets were significantly lower than in other diet treatme...

Effects of the Dietary Fermented Tuna By‐product Meal on Growth, Blood Parameters, Nonspecific Immune Response, and Disease Resistance in Juvenile Olive Flounder, Paralichthys olivaceus

AbstractThis study evaluated the effects of dietary fermented tuna by‐product meal (FTBM) in juvenile olive flounder, Paralichthys olivaceus. Five diets were formulated to replace fishmeal (FM) with FTBM at 0% (FTBM0), 12.5% (FTBM12.5), 25.0% (FTBM25), 37.5% (FTBM37.5), or 50% (FTBM50). After 8 wk, weight gain, specific growth rate, and feed efficiency of fish fed FTBM0 and FTBM12.5 diets were significantly higher than fish fed the other diets (P &lt; 0.05). Also, mean cumulative survival rates (%) of fish fed the FTBM0 and FTBM12.5 diets were significantly higher than those fed FTBM50 diet at Day 9 postchallenge with Edwardsiella tarda (P &lt; 0.05). Protein efficiency ratio of fish fed FTBM0 and FTBM12.5 diets was significantly higher (P &lt; 0.05) than fish fed diets FTBM37.5 and FTBM50. Broken‐line regression analysis of weight gain showed an optimal FM replacement level of 10.65% with FTBM. Therefore, the optimal dietary inclusion of FTBM in juvenile olive flounder diets could be greater than 10.65% but less than 12.5% without any adverse physiological effects on fish health.

Evaluation of genetically-improved (glandless) and genetically-modified low-gossypol cottonseed meal as alternative protein sources in the diet of juvenile southern flounder Paralichthys lethostigma reared in a recirculating aquaculture system

Cottonseed meal (CSM) proteins from genetically-improved (glandless) low-gossypol seed (GI-CSM, 52.1% crude protein, CP), genetically-modified low-gossypol seed (GMO-CSM, 56.0% CP) and from an untreated regular (glanded) seed (R-CSM 49.9% CP) were evaluated to replace fish meal (FM) protein (59.5% CP) in juvenile southern flounder Paralichthys lethostigma diets. Eight isonitrogenous (45% CP) and isolipidic (16% crude lipid, CL) diets were formulated. A control diet (0% CSM) contained 40% fishmeal (FM) and other practical protein sources. Six diets replaced 50, 75 and 100% FM protein with GI-CSM or GMO-CSM protein. One diet replaced 100% FM protein by R-CSM protein. Fifteen fish (mean = 1.81 g) were stocked in each of twenty-four 75-L tanks (N = 3 per treatment) and were fed the treatment diets for eight weeks. Final percent weight gain was not significantly (P > 0.05) different in fish fed the GI- and GMO- and R-CSM protein diets (898–1405%) compared with the control diet (0% CSM) (1242%), but percent weight gain was greater (P < 0.05) in fish fed the 50% GI-CSM diet (1405%) versus the 100% GI-CSM diet (898%). Feed conversion ratio was excellent for all treatments (FCR = 0.70–1.00), with no treatment differences (P < 0.05). Protein efficiency ratios (PER) were also not significantly different among the treatments (2.26–3.24), although the lowest value was for 100% R-CSM diets. After 8 weeks of feeding, survival of fish ranged from 80 to 91%, with no treatment differences. Apparent protein digestibility of diets was significantly higher for the fish fed 75% and 100% GI-CSM and 100% GMO-CSM protein diets (83.5, 83.5 and 86.5%, respectively) compared with the control diet (79.4%). After 8 weeks, no significant (P > 0.05) interactive effects between CSM sources and FM replacement levels on final weight, FCR and PER were observed. Arginine levels in the diets increased as CSM was increased, consistent with the high arginine concentrations found in CSM. Liver gossypol was only detectable in fish fed the 100% R-CSM diet (37 μg/g). Replacing up to 75% FM protein by GI- or GMO-CSM protein did not affect on whole body omega-3 PUFAs, or liver gossypol. The results suggest that up to 75% of fish meal protein may be replaced by GI- or GMO-CSM protein in the diet of juvenile flounder without adverse effects on growth performance and body composition. Statement of relevanceCottonseed meal (CSM) is a potentially cost-effective alternative plant protein source for use in aquafeeds. The results suggest that a 75% of fishmeal protein could be replaced by genetically-improved and genetically modified (GMO) low gossypol based cottonseed flour protein in the diet of southern flounder. These ultra-low gossypol cottonseed flour proteins could be inexpensive protein sources for the commercial culture of southern flounder and other finfish species.

Influence of a sodium formate/formic acid mixture on growth of juvenile common carp (Cyprinus carpio) fed different fishmeal replacement levels of detoxified Jatropha curcas kernel meal in practical, mixed diets

ABSTRACTIntensification of cyprinid production has resulted in substantial increases in aquafeed demand for these species and a requirement for studies on new protein sources. Increased availability of presscakes from biodiesel crops may help to meet this requirement. The suitability of detoxified Jatropha curcas kernel meal (JKM), in combination with a dietary organic acid/salt blend (NDF), was tested in practical diets for juvenile common carp (Cyprinus carpio). Four treatment diets contained between 0% and 13.5% fishmeal with the fishmeal protein replaced by JKM (0%, 30%, 70%, and 100%). Four further diets of the same composition but including 0.5% NDF were also prepared, and all diets were fed to carps for eight weeks. There were no statistical differences in growth between diets containing JKM and the control. Furthermore, addition of dietary NDF significantly improved final weights, specific growth rates, feed conversion ratios, and protein efficiency ratios. Body composition analysis showed a significant impact of dietary JKM inclusion on increasing body lipid content. The addition of NDF showed a tendency to lower body lipid content (P = 0.11). JKM is a suitable protein source in diets for carp, and the inclusion of 0.5% of NDF proved to be beneficial.

Utilization of poultry by-product meal supplemented with L-lysine as fish meal replacer in the diet of African catfish Clarias gariepinus (Burchell, 1822)

ABSTRACTThe study was designed to evaluate the effect of dietary L-lysine supplementation on growth performance and feed utilization of African catfish fingerlings fed diet containing high levels of slaughterhouse poultry by-product meal (SPB). Control diet (CD) without amino acid supplementation or SPB inclusion contained 40% of fish meal (FM) and 20% of soybean meal (SBM), four isonitrogenous and isocaloric diets formulated to represent two levels of SPB (50% and 75%) with two levels of L-lysine supplementation (0.0 and 1.0%), SPB50%0.0, SPB50%1.0, SPB75%0.0 and SPB75%1.0, where the subscripts and superscripts refer to the replacement level of FM with SPB and L-lysine supplementation level respectively. Growth performance and feed utilization in terms of final body weight (FBW), weight gain (WG), feed intake (FI), and specific growth rate (SGR) tended to decrease as SPB levels increased from 50% to 75% with or without L-lysine supplementation. Protein retention (PR) was not significantly different between fish fed CD and those fed SPB50%0.0. Energy retention (ER) was not significantly different between fish fed CD and those fed SPB50%0.0 and SPB75%1.0. Lipid, protein, moisture, and ash of fish fed the experimental diets were not statistically significantly different than the control diet. The partial replacement of FM at the rate 50% and 75% with SPB is possible in diets for African catfish, especially with 1% L-lysine supplementation, and could match growth performance of FM diets, as well as minimize feed cost and improve profitability.

Integrated study on production performance and quality traits of European sea bass (Dicentrarchus labrax) fed high plant protein diets

In the issue of fishmeal replacement, besides maintaining optimal growth, a key area of investigation for continuing to improve modern aquafeeds includes the evaluation of the effects of plant ingredients on fish quality. It is generally accepted that farmed fish quality can be influenced by the formulation of composition of their feed. Hence, the aim of the present research was to evaluate plant protein inclusion up to 84% of the overall protein content in an integrated study on growth and quality traits of European sea bass. Three diets were formulated to contain increasing plant protein levels (50, 67 and 84%; 50PP, 67PP and 84PP, respectively), with fishmeal dietary levels at 30, 20 and 10%, respectively. No significant differences due to reducing fishmeal content were observed after 118 days in terms of growth (final body weight and specific growth rate) and feed intake, even though a trend towards lower growth performance at higher fishmeal replacement levels was observed. Fish fed diet 50PP showed lower feed conversion rate in comparison to those fed diet 84PP, while no differences were recorded between diet 50PP and 67PP. No significant differences among treatments were found in protein efficiency rate. On the contrary, fish fed diet 84PP showed lower gross protein efficiency in comparison to those fed diet 50PP and 67PP. No significant differences in biometric indices and fillet composition were observed. No significant differences were found in pH, liquid holding capacity and skin colour measurements between treatments, while regarding fillet colour, significant differences were found only for H°ab. In conclusion, our findings demonstrated that dietary plant proteins up to 84% of the overall protein content had no effects on quality traits of European sea bass in comparison with 50% and 67%. All experimental groups showed similar growth even though 84% plant protein inclusion negatively influenced feed and protein utilisation.