Partial Substitution Of Fish Meal Research Articles

Partial substitution of fish meal by biofloc meal in diets for Nile tilapia Oreochromis niloticus

The effect of a partial substitute of fish meal by biofloc meal on the growth and survival of fry Nile tilapia Oreochromis niloticus was evaluated over nine weeks. Two biofloc meals were obtained by drying them in two processes: A) sun exposure and B) convection oven. A randomized design of eight isonitrogenous (40%) and isoenergetic (17 kJ g-1) diets was used, where 5, 10, 15, and 20% of the fish meal was substituted for the two biofloc meals. The nutritional study was conducted in a recirculating aquaculture system with Nile tilapia fry (initial weight: 0.64 ± 0.16 g). The survival range was similar in all treatments and higher than 97%. Tilapia fed with the treatments A5, A10, B5, and B10 of substitution of biofloc meal showed similar and significantly better final weight, individual weight gain, specific growth rate, and condition factor than A15, A20, B15, and B20 treatments; as well as efficiency of use of the feed: protein efficiency ratio, carcass nitrogen deposition, apparent nitrogen utilization, and apparent digestibility. Therefore, these results suggest that biofloc meal is possible in diets for tilapia, thus reducing the need for fishmeal as the main source of protein in the diet.

Dietary Tenebrio molitor larvae meal effects on cellular stress responses, antioxidant statusand intermediate metabolism of Oncorhynchus mykiss.

In the context of evaluating the impact of environmentally friendly and sustainably produced alternative protein sources in fish feed, the present study's aim was to examine the overall physiological stress response in one of the main fish species of European freshwater aquaculture, Oncorhynchus mykiss (rainbow trout), following the partial substitution of fish meal (FM) with a Tenebrio molitor (TM) (yellow mealworm) full-fat meal. In total, 222 rainbow trout individuals (115.2 ± 14.2 g) were allocated randomly into six tanks, three per dietary treatment, and were fed a formulated diet containing 60% yellow mealworm (TM60) compared to a control diet without insect meal (TM0). Both diets contained equal amounts of crude protein, dry matter and, lipid content, while the FM in TM60 was 100 g kg-1 corresponding to the one seventh of the TM0. Heat shock response (HSR), MAPK signalling, cell death pathways (apoptosis and autophagy), antioxidant defence mechanisms, and intermediate metabolism were evaluated. In general, HSR and MAPK signalling were activated in response to the inclusion of T. molitor. Moreover, triggering of apoptotic and autophagic processes and the onset of antioxidant defence mechanisms underlined the existence of physiological stress. Despite the apparent dietary-induced stress, rainbow trout in the present study exhibited no mortality and no significant effects regarding growth performance parameters. Specifically, TM60 dietary inclusion resulted in no changes in final body weight, weight gain, and specific growth rate. However, feed intakedepicted a statistically significant decrease in TM60 fish compared to TM0 individuals. Nevertheless, nutrient stress should be considered a limiting factor regarding the utilization of T. molitor in O. mykiss diet due to the associated risks for health and welfare.

Effects of Partial Substitution of Fish Meal with Soybean Products and Chicken Meal on Growth, Antioxidant Capacity and Intestinal Microbiota of Penaeus monodon

The aim of this experiment was to investigate the effects of the partial substitution of fish meal with soybean products and chicken meal on the growth performance, antioxidant capacity and intestinal microbiota of Penaeus monodon. A total of 450 healthy, consistent shrimp were randomly divided into five groups, with three replicates per group and 30 shrimp per replicate. The proportion of fish meal substituted with soybean products and chicken meal in the five feed groups was 0% (FM), 40% (40SC), 60% (60SC), 80% (80SC) and 100% (100SC). The experiment lasted for 8 weeks. The results showed that, compared to the FM group, the 40SC and 60SC groups had a decrease in WG and SR, but there was no significant difference (p > 0.05). In contrast, compared to the FM group, the FCR in the 100SC group was significantly increased (p < 0.05), while there was no significant difference among the FM and 40SC, 60SC and 80SC groups (p > 0.05). Compared to the FM group, the ACP in the 80SC and 100SC groups significantly increased (p < 0.05), while the 40SC and 60SC groups had no significant difference (p > 0.05). The AKP in the 100SC group was significantly higher than that in the FM group (p < 0.05), while there were no significant differences among the other four groups (p > 0.05). There were no significant differences in T-AOC and T-SOD among all the treatment groups (p > 0.05). The next-generation sequencing of the intestinal microbiota showed that Proteobacteria was the most abundant phylum in the five groups, accounting for 37.67%, 66%, 40%, 40% and 43.33%, respectively. Compared to the FM group, the Fusobacteriota in the other four groups decreased significantly (p < 0.05). The functional prediction of FAPROTAX indicated that no functional components were observed which are harmful to the body. Considering the effects on growth performance, antioxidant capacity and intestinal microbiota, it is feasible to use soybean products and chicken meal to replace 60% of fish meal in the feed of P. monodon.

Partial Substitution of Fish Meal with Soy Protein Concentrate on Growth, Liver Health, Intestinal Morphology, and Microbiota in Juvenile Large Yellow Croaker (Larimichthys crocea).

The present study investigated the growth performance, feed utilization, intestinal morphology, and microbiota communities of juvenile large yellow croaker (Larimichthys crocea) fed diets containing different proportions of soy protein concentrate (SPC) (0, 15%, 30%, and 45%, namely FM, SPC15, SPC30, and SPC45) as a substitute for fish meal (FM) for 8 weeks. The weight gain (WG) and specific growth rate (SGR) in fish fed SPC45 were significantly lower than those fed FM and SPC15 but not differ with these fed SPC30. The feed efficiency (FE) and protein efficiency ratio (PER) decreased sharply when the dietary SPC inclusion level was higher than 15%. The activity of alanine aminotransferase (ALT) and expression of alt and aspartate aminotransferase (ast) were significantly higher in fish fed SPC45 than those fed FM. The activity and mRNA expression of acid phosphatase were opposite. The villi height (VH) in distal intestine (DI) showed a significant quadratic response to increasing dietary SPC inclusion levels and was highest in SPC15. The VH in proximal intestine, middle intestine decreased significantly with increasing dietary SPC levels. The 16S rRNA sequences in intestine revealed that fish fed SPC15 had higher bacterial diversity and abundance of Phylum Firmicutes such as order Lactobacillales and order Rhizobiaceae than those fed other diets. Genus vibrio, family Vibrionaceae and order Vibrionales within phylum Proteobacteria were enriched in fish fed FM and SPC30 diets. Tyzzerella and Shewanella that belongs to phylum Firmicutes and Proteobacteria, respectively, were enriched in fish fed SPC45 diet. Our results indicated that SPC replacing more than 30% FM could lead to lower quality diet, retard growth performance, ill health, disordered intestine structure, and microbiota communities. Tyzzerella could be the bacteria indicator of intestinal in large yellow croaker fed low quality diet due to high SPC content. Based on the quadratic regression analysis of WG, the best growth performance could be observed when the replacement of FM with SPC was 9.75%.

Partial Substitution of Fishmeal and Fish Oil in a Semi-Purified Diet for Noble Crayfish, Astacus astacus (Linnaeus, 1758)

Continuous environmental disturbances and the crayfish plague have restricted freshwater crayfish populations in Greece. Therefore, the need for the establishment of a repopulation policy in Greece and the increasing commercial interest for the species, dictated in the Thessaly County, have imposed the investigation of the optimum husbandry and dietary requirements of Astacus astacus in culture conditions. Hundred and five adult crayfish were placed in cement tanks for 60 days and fed a semipurified diet, whereas 90 adult crayfish were placed in similar cement tanks for the same time period and fed a control diet consisting of fresh fish and carrots. The semipurified diet had a Protein: Energy ratio of 21.29 mg Prot. kJ–1, a protein level of 37.95%, and a lipid level of 9.6% (on a Dry Matter basis). By the end of the experiment, crayfish fed the semipurified diet gained almost 5 g of weight with acceptable survival rates. Despite the total substitution of corn oil by soy oil and the partial substitution of fish oil (by 3%) and fishmeal (by 7%) with other plant-derived materials, in comparison with their levels in the semipurified diet of a previous experiment, dietary linoleic, and linolenic acids have been substantially high whereas dietary arachidonic acid and EPA, DHA have been somehow lower compared with the respective ones of the semipurified diet of a previous experiment. Although EPA tail muscle tissue has been progressively augmented throughout the experiment, DHA respective levels seemed to stay unaffected and at similar levels throughout the experiment. These results dispute the ability of noble crayfish for bioconversion of EPA to DHA and call for further investigation.

The positive impact of partial substitution of fish meal by a meal mixture of duckweed and mealworm larvae on the diets of Nile tilapia fry (Oreochromis niloticus Linnaeus, 1758)

In ordre to promote aquaculture in the south of the country, and specifically, to reduce the cost of feeding farmed fish, this study was carried out to evaluate the effect of partial replacement of fishmeal with a mixture of duckweed meal (DWM) and mealworm larvae (WLM) on growth performance, feed utilization and carcass composition of Nile tilapia. Eight-week feeding experiment was conducted on fry of O. niloticus (average initial weight: 0.87 ± 0.23 g). Four isoproteic diets (38.52 ± 0.11% crude protein) comprising control diet D0 and three test diets (D1 to D3) were formulated and tested in triplicates. To satisfy EAA requirements in test diets, the ratios 1: 5; 2: 4 ; 4: 2 between DWM and WLM were used respectively in partial replacement for fishmeal. No significant differences (P > 0.05) were observed in survival, growth and feed utilization. On the other hand, the compositions of the carcasses showed strong significant differences (P < 0.05) except ash contents. The carcass lipid increased proportionally with the inclusion of WLM, but the reverse was true for the moisture content. However, the high contents of retained proteins were obtained in the ratios 0 : 0 and 4 : 2 between D0 and D3. It is concluded that fishmeal could be replaced by a meal mixture of DWM and WLM up to the proportion (4 : 2, respectively) in the feed of O. niloticus without adverse effects on growth and nutrient utilization and most importantly, reduce the cost of production up to 29.8% which would have a positive impact on post-feeding and therefore the financial management of an aquaculture farm.

Partial Substitution of Fishmeal with Mopane Worm Meal in Dusky Kob Fingerling (Argyrosomus japonicus) Diets: Feed Utilization, Digestive Enzyme Activity, Blood Parameters, and Growth Performance

The use of protein-rich mopane worm meal (MPWM) in marine fish diets has the potential to reduce the overall demand for fishmeal (FM) and thus promote economically and ecologically sustainable dusky kob aquaculture. Therefore, this study investigated the effect of graded levels of MPWM on feed and nutrient utilization, digestive enzymes, blood parameters, and growth performance in dusky kob fingerlings (Argyrosomus japonicus, Temminck and Schlegel, 1843) over a 7-week feeding trial. Five isonitrogenous and isoenergetic commercial dusky kob diets were formulated by substituting 0 (MPWM0), 3 (MPWM3), 6 (MPWM6), 9 (MPWM9), and 18% (MPWM18) of FM with MPWM and offered at 2.8% of fish body weight. Two-thousand fingerlings (average weight 15.68 ± 0.25 g) were evenly distributed into 20 experimental tanks of a recirculating aquaculture system. Weight measurements were taken weekly, while blood and intestinal samples were taken at the end of the experiment. The inclusion of MPWM quadratically influenced (y = 39.25 (±1.27) + 0.89 (±0.36)x − 0.04 (0.02) x2; R2 = 0.23; p = 0.03) overall feed intake. Overall weight gain and specific growth rate (SGR) linearly increased while overall feed conversion ratio (FCR) linearly declined with MPWM inclusion levels. Substituting FM with MPWM did not alter (p > 0.05) digestive enzyme activities and haematological parameters. Among the serum biochemical components measured, only urea increased linearly in response to MPWM levels, while no trends were observed for the other components. It was concluded that replacing 11.13% of FM with MPWM in commercial dusky kob diet formulations does not compromise feed intake, feed utilization efficiency, growth rate, and physiological status of juvenile dusky kob.

Insect meals as emerging protein source in the aquafeed sector: Emphasis on complementary effects to fishmeal, digestibility, carcass characterisation and immunomodulation in aquatic species

Insect meals received great attention in the aquafeed sector during the past decade due to the unsustainable demand for fishmeal. Desirable nutrient content, especially protein with balanced amino acids is of great importance in the use of insect meals as a viable protein source in aquafeeds. Insect meal could complement about 20-75% of dietary fishmeal in various aquatic species. They have better digestibility compared to low-quality fishmeal, oil meals/cakes, fermented plant proteins, feather meal; blood and meat meal and showed equal performance to high-quality fishmeal. Though partial substitution of fishmeal using insect meals could promote the health status, complete substitution resulted in detrimental effects in some aquatic species. This review concludes that insect meals are of great importance as a sustainable protein source and a viable complement to fishmeal in aquafeeds, thereby, helping to reduce the tremendous demand on fishmeal.Keywords: Aquafeed, Carcass characterisation, Fishmeal, Immunomodulatory effect, Insect meal

Influences of Partial Substitution of Fish Meal with Defatted Black Soldier Fly (Hermetia illucens) Larvae Meal in Diets on Growth Performance, Biochemical Parameters, and Body Composition of Juvenile Chinese Soft-Shelled Turtles (Pelodiscus sinensis)

The black soldier fly (Hermetia illucens) larvae meal (BSFM) has been widely applied in aquaculture production due to its rich nutritional value, easy availability, and renewability. However, to our knowledge, it has not been used in the diets for turtles. Here, we evaluated the acceptability of partial substitution of fish meal (FM) with defatted BSFM in the diets of juvenile Chinese soft-shelled turtles (Pelodiscus sinensis). A total of 225 juvenile turtles were randomly divided into D1, D2, D3, D4, and D5 groups, which were fed with BSFM replacing 0, 5%, 10%, 15%, and 20% FM, respectively, for 70 days. The results showed that growth performances of groups D2 and D3 were not significantly different ( P > 0.05 ) from that of group D1, whereas the growth performance compromised ( P < 0.05 ) in groups D4 and D5. The activity of serum alkaline phosphatase was higher ( P < 0.05 ) in group D3 relative to other groups, while alanine aminotransferase and aspartate aminotransferase activities were higher ( P < 0.05 ) in group D4 when compared with groups D1, D2, and D3. Liver lysozyme activity and malonaldehyde level were significantly higher ( P < 0.05 ) in group D1 relative to other groups, whereas total antioxidant capacity activity showed the opposite trend ( P < 0.05 ). The activities of hepatic total superoxide dismutase and glutathione peroxidase displayed a linear elevation ( P = 0.011 and P < 0.001 , respectively) from groups D1 to D3. Intestinal amylase and protease activities linearly increased ( P < 0.001 ) with increasing BSFM levels, while intestinal lipase activity showed a quadratic increase and then a decrease with increasing BSFM levels ( P = 0.011 ). Muscle crude protein and fat contents increased ( P < 0.05 ) in group D3 when compared with groups D1 and D2. Muscle phenylalanine, glutamic, tryptophan, and arginine levels increased in group D1 in comparison with the other groups ( P < 0.05 ), whereas the opposite was true for isoleucine and proline levels. The broken-line analysis based on specific growth rate estimated that the optimal level for replacing dietary FM with BSFM is 5.0%, which could elicit benefits on both the growth performance and physiological health condition of the juvenile Chinese soft-shelled turtles.

Valorization Use of Amphipod Meal, Gammarus pulex, as a Fishmeal Substitute on Growth Performance, Feed Utilization, Histological and Histometric Indices of the Gut, and Economic Revenue of Grey Mullet

The future of aquaculture development is directed toward high intensification to overcome the decline in natural fishing and to provide enough protein for the increasing world population. The spread of aquaculture production and intensification requires the search for high-quality, new efficient feed ingredients with low cost and sustainable importance. Therefore, the current study aimed to detect the effects of partial or total replacement of fishmeal with amphipod meal, Gammarus pulex, on growth performance, survival percent, feed utilization, histological alteration of intestine and liver, and economic yield of grey mullet, Mugil cephalus, fry. Five diets were formulated to contain 100% fishmeal (FM), or FM replaced with 25%, 50%, 75%, or 100% amphipod meal (APM) (D0, D25, D50, D75, and D100, respectively). A total of 300 grey mullet fry (0.097 ± 0.001 g), were divided into five groups (three replicates each) at an initial stocking density of 20 fry per aquaria (100 L). The aquarium’s water is renewed at a rate of 30% daily. During a 60-day experimental period, the feeding rate was 20% of body weight, which was introduced as five meals per day. Fish fed D50 achieved the highest significant values of final weight (1.80 g), weight gain (1.70 g), survival (86.67%), final length (4.47 cm), and length gain (2.06 cm). In addition, the feed utilization of diets containing increasing substitution levels of FM showed that the highest protein intake (0.82 g ish−1), protein efficiency ratio (0.83), protein productive value (30.65%), and the lowest significant feed conversion ratio (1.21) were recorded with D50. The dose-response study revealed that the best substitution levels could range between 50% and 75%. Histological observations confirmed that the highest number of goblet cells and intestinal villi were recorded in the group fed D50. No pathological effect was observed in the liver at all substitution levels. In terms of economic efficiency, the best economic conversion ratio was recorded in the group fed D50. This study confirmed that 50% partial substitution of FM with APM is the ideal replacement level for grey mullet fry. In addition, the use of a new renewable alternative, such as APM to substitute FM, could relieve the pressure on the capture of wild fish and reduce the environmental impact of inland aquaculture.

Partial substitution of fish meal by Clostridium autoethanogenum protein in the diets of juvenile largemouth bass (Micropterus salmoides)

The present study was conducted to investigate the effect of fish meal replacement with Clostridium autoethanogenum protein (CAP) on growth performance, haemato-biochemistry, digestive capacity, antioxidant index, and histopathological examination of liver and intestine in largemouth bass (Micropterus salmoides). Seven experimental diets were formulated with CAP replacement of 0% (CAP0), 15% (CAP15), 27% (CAP27), 39% (CAP39), 51% (CAP51), 63% (CAP63) and 75% (CAP75) fish meal, respectively. Results showed that replacement of fish meal by CAP did not affect SR, FBW, WGR, SGR and CF. While the fish fed diets containing CAP displayed a higher PER and a lower FCR than the control group (P < 0.05). However, the CAP inclusion level did not statistically affect the whole-body composition (P > 0.05). Additionally, The ADC of dry matter and protein were improved by addition of CAP (P < 0.05), while corresponding ADC of lipid were not significantly changed among different groups (P > 0.05). The lipase and amylase activities were not dramatically altered in stomach (P > 0.05), but were significantly increased in intestine with dietary substitution level up to 39% (P < 0.05). Differently, the protease activity of fish fed CAP75 was higher than other groups in stomach and intestine (P < 0.05). In addition, the activities of T-AOC and SOD in serum, liver and intestine were elevated with dietary CAP level (P < 0.05), whereas MDA content displayed the opposite trend. Moreover, the increased TP, ALB, TC, TG and AST/ALT were observed in treatment groups. In addition, the villus length and width of hindgut were dramatically increased with increasing dietary substitution level up to 39%. Furthermore, no adverse effect on the hepatic histology was occurred when fed diet with substitution level below 63%. Overall, the optimal CAP replacement level was 49.80% with maximum weight gain rate of juvenile largemouth bass.

Effect of partial substitution of fishmeal with insect meal (Hermetia illucens) on gut neuromuscular function in Gilthead sea bream (Sparus aurata)

Alternative nutrient sources to fishmeal for fish feed, such as insect meals, represent a promising sustainable supply. However, the consequences for fish digestive function have not been exhaustively investigated. In the present study we evaluated the effect of partial fishmeal substitution with 10% Hermetia illucens (Hi10) larvae meal on the neuromuscular function of proximal and distal intestine in gilthead sea bream. In animals fed with insect meal, weight and growth parameters were similar to controls fed with conventional fishmeal. In addition, no anomalies in intestinal gross morphology and no overt signs of inflammation were observed. The gastrointestinal transit was significantly reduced in Hi10 fed animals. In the proximal and distal intestine longitudinal muscle, Hi10 feeding downregulated the excitatory cholinergic and serotoninergic transmission. Sodium nitroprusside-induced inhibitory relaxations increased in the proximal intestine and decreased in the distal intestine after Hi10 meal. Changes in the excitatory and inhibitory components of peristalsis were associated with adaptive changes in the chemical coding of both proximal and distal intestine myenteric plexus. However, these neuromuscular function alterations were not associated with considerable variations in morphometric growth parameters, suggesting that 10% Hi meal may represent a tolerable alternative protein source for gilthead sea bream diets.

Soy protein concentrate effects on gut microbiota structure and digestive physiology of Totoaba macdonaldi.

Examine the effect of soy protein concentrate (SPC) on allochthonous microbiota, hindgut integrity, and liver tissue of totoaba (Totoaba macdonaldi). Four diets were prepared: control diet (100% fishmeal) and experimental diets containing partial substitution of fishmeal by SPC (15%, 30% and 45% SPC). After 90days, samples of the hindgut contents were taken to determine the taxonomic composition of the allochthonous microbiota through sequencing of the V3-V4 region of the 16S rRNA gene. Simultaneously, liver and hindgut samples were collected for examination by histological approaches. The SPC modulated the richness and abundance of the accessory microbiota, of which the main operational taxonomic unit showed an increase corresponding to the Phylum Firmicutes (Bacillales and Lactobacillales). With the increase in SPC, a slight decrease in mucosal fold width, a decrease in goblet cells and a slight distortion of the villi in the hindgut were observed. In the liver, SPC was observed to influence hepatocytes morphology through irregular and enlarged nuclei. The study demonstrates that Proteobacteria dominated the allochthonous microbiota of subadult totoaba, regardless of the diet. However, the SPC modulated the accessory bacteria communities and caused slight effects on the liver and gut of fish. To our knowledge, this is the first study that analyses the effects of SPC on allochthonous microbiota of subadults T. macdonaldi through new generation techniques such as DNA sequencing for metagenomic analysis.

Effect of a New Feed Daphnia magna (Straus, 1820), as a Fish Meal Substitute on Growth, Feed Utilization, Histological Status, and Economic Revenue of Grey Mullet, Mugil cephalus (Linnaeus 1758)

The formulator of aquatic diets is part of a continuous search for alternative protein sources instead of depreciated fish meal. The utilization of zooplankton as a feed ingredient is an interesting trend due to their high-quality protein content and abundance of essential nutrients. The current study aims to investigate the effects of partial and total replacement of fish meal (FM) by Dahpnia magna meal (DMM) on growth performance, feed utilization, histological, and economic status of mullet, M. cephalus, larvae. In addition to the control diet, 100% FM, D0, four diets containing DMM at different levels were used: 25% (D25), 50% (D50), 75% (D75), and 100% (D100) replacement of fish meal. A total of 300 larvae (0.097 ± 0.001 g) were equally divided into five groups (three replicate per each group) at a density of 200 larvae m−3. The aquariums were renewed at a rate of 30% daily. During the 60-day experimental period, all larvae were fed their respective diets at a level of 20% of live body weight, five times a day (9.00 a.m., 12.00, 15.00, 18.00, and 21.00 p.m.). The results indicated that compared to D0, fish fed D75 recorded the highest significant value of growth, and feed utilization parameters, while fish fed D100 achieved the lowest feed cost and incidence cost, and the highest profit index and economic efficiency ratio. A strong correlation was reported among weight gain, feed conversion ratio and fish meal replacement with DMM; R2 = 0.94 and 0.91, respectively. The fit regression model representing mullet response to FM replacement with DMM is a poly-nominal regression model with maximum response at 75–100%. The histological investigation of the intestine revealed an improvement of histomorphometric indices and goblet cell number with increasing DMM inclusion levels. These findings confirmed that 75% to 100% partial substitution of FM with DMM is the ideal replacement for mullet, M. cephalus, larvae for improving fish growth performance and feed utilization.

Effects of partial substitution of fish meal with different levels of marine macroalgae species on growth indices and RNA/DNA ratio of hybrid red tilapia

A 90-days experiment was conducted to determine the impact of partial replacement of dietary fish meal (FM) with different concentrations of ultra-fine powder of Ulva lactuca, Laurencia obtusa and Cystoseira myrica on growth performance, feed utilization and RNA/DNA ratio of the hybrid red tilapia “Florida strain”.

Preliminary evaluation of Superworm ( Zophobas morio ) larval meal as a partial protein source in experimental diets for juvenile Asian sea bass, Lates calcarifer

A 12-week feeding trial with Asian sea bass Lates calcarifer juveniles was conducted to evaluate the response of feeding defatted Superworm (Zophobas morio) larval meal on growth performance, feed utilization, apparent digestibility coefficient of nutrients and haemato-biochemical status for Asian sea bass. Five isonitrogenous (450 g/kg) and isolipidic (125 g/kg) experimental diets were formulated. A basal diet that contained no insect meal from defatted Superworm (DFSM) served as the control. Four diets were formulated where DFSM was included at 30 g/kg; 11.11% (DFSM-3), 60 g/kg; 22.22% (DFSM-6), 90 g/kg; 33.33% (DFSM-9) and 120 g/kg; 44.44% (DFSM-12), respectively, on a dry matter basis. All essential amino acids (EAA) except methionine, phenylalanine and threonine in DFSM compared favourably with fishmeal (FM) and arginine, histidine, isoleucine, leucine, tryptophan and valine were higher than that of FM. No significant (p > .05) differences in weight gain, specific growth rate and feed conversion ratio, hepato-somatic and viscera-somatic index were apparent among fish fed different levels of DFSM. Furthermore, no significant (p < .05) differences were found for apparent digestibility of dry matter (DM) and crude fat in response to dietary DFSM with different levels. A significant decreased linear relationship in the ADC of protein (p = .042) was noted as the level of DFSM incorporation increased in the experimental diet. No significant differences in haematocrit, MCHC and creatinine values were found among the experimental diets. However, a significant quadratic increase in haematocrit (p = .039) was detected as the level of DFSM increased in the diet. Serum cholesterol, alkaline phosphatase (ALP), glutamic pyruvic transaminase (GPT) and glutamic oxaloacetate transaminase (GOT) were linearly reduced with the increasing of dietary DFSM (linear, p = .043; p = .023; p = .018; p = .028). The findings of the present study indicated that growth, feed efficiency and haemato-biochemical indices were not adversely affected by partial substitution of FM up to 120 g/kg dietary inclusion of Superworm meal. We discuss this in the context of aquafeed applications for marine fish production in Asia for more sustainable production using novel protein ingredients and wider implications.

Effect of protein ratio with partial substitution of fish meal by plant protein on the performance of Bayad fish fingerlings

A factorial experiment 2 × 2 was conducted to investigate the effect of protein ratio (30% and 35%) with different fish meal and plant protein percentage (50% fish meal: 50% plant protein, and 33% fish meal: 67% Plant protein) on the growth performance, feed utilization, survival rate and economical evaluation of Bayad (Bagrus bajad) fingerlings with average weight 31.86 ±0.34g as an initial body weight. The survival rate was within the range 96.67–100 %. The highest growth parameters and the best FCR (lowest) were obtained with the diet contained on (35% CP and 50% FM: 50% PP). The diet contained (30% CP and 33% FM: 67% PP) had the lowest growth and the worst FCR than other treatments. However, differences in growth parameters among diets contained on (30% CP, 50% FM: 50% PP) and (35% CP, 33% FM: 67% PP) were insignificant. Final body weight was progressively decreased with increasing plant protein under both protein levels of diets. The improvement of growth performance and FCR tested in diets containing higher levels of fish meal under both protein levels of diets. Regarding to economical evaluation 35% protein level is more economical in Bayad aquaculture. Net returned of Bayad were better for the 35% treatment (50 FM: 50 PP) which was 1.20 but the worst was 30% (33 FM: 67 PP) which was 0.77. It could be concluded that 35 % and 30% crude protein levels were the best under composition of the diet ((50 FM: 50 PP).

Partial Substitution of Fishmeal with Plant Protein Source the Soybean Meal in the Diets of Arabian Yellowfin Seabream Acanthopagrus arabicus Juveniles

The present study was designed to assess the alternate environmental friendly source of protein; here we report the suitability of soybean meal as a plant protein source for partial replacement of fishmeal in the diet of Arabian yellowfin seabream Acanthopagrus arabicus; reared in floating net cages. A total of 56 days feeding trial was conducted to evaluate the growth performance, feed utilization, survival, and carcass composition of the juveniles. Triplicate groups (30 fish/cage) of A. arabicus (initial weight 22.61 ± 0.11 g) were stocked in floating net cages (1.5 × 1.5 × 1.5 m). Five semi-purified experimental diets, each containing 42% dietary protein, were prepared where fishmeal was replaced with soybean meal: 0% (control), 20% (SBM20), 40% (SBM40), 60% (SBM60) and 80% (SBM80). Fish were fed twice daily at 7% body weight. The formulated diet was well accepted by the fish, where, 100% of survival was recorded at the end of the experiment. No significant differences (P > 0.05) were observed in final weight gain (WG) and specific growth rate (SGR) of juvenile Arabian yellowfin seabream fed on SBM20 and SBM40 diets compared to the control diet. However, a decline in growth performance was recorded in fish received SBM60 and SBM80 diets. Poor feed conversion ratio (FCR) was observed for fish fed with increasing dietary soybean meal above SBM40. No significant differences (P > 0.05) were found in the final whole-body carcass composition of proteins, moisture, and ash. However, the lipid content in the fish body increased significantly (P < 0.05) with an increasing soybean meal and fish oil in the diets. Our results showed that 40% of SBM could substitute fishmeal without jeopardizing the health and growth of Arabian yellowfin seabream.

Impact of partial substitution of fish meal by methylated soy protein isolates on the nutritional, immunological, and health aspects of Nile tilapia, Oreochromis niloticus fingerlings

The impact of partial replacement of fish meal with methylated soy protein isolates (MSPI) on fish performance was assessed in 10 weeks feeding trial using Nile tilapia,Oreochromisniloticusfingerlings (n = 225) with average initial weight 18.51 ± 0.05 g/fish. The effects on the growth, histopathological condition of certain organs, economic efficiency, immune status, and disease resistance to Aeromonashydrophila were evaluated. The fingerlings were randomly segregated into five experimental groups with varying percentages of fish meal with substituted MSPI: 0%, 22%, 44%, 66%, and 88% (MSPI0, MSPI22, MSPI44, MSPI66, and MSPI88). The results of final body weight, body weight gain, daily body weight gain, protein efficiency ratio,and SGR were uniquely increased by the treatment MSP22, while increasing the level of MSPI more than 22% resulted in linearly proportional decreases in these parameters over the respective control. The broken-line regression analysis using feed conversion ratio and body weight gain data revealed that the maximum dietary replacement of fishmeal with MSPI was 66%. Alterations in the histomorphological structures of the liver and intestine were observed with an increased level of replacement.The total weight of surviving fish, phagocytic index, IgM level, and lysozyme activity post bacterial challenge were significantly increased by MSPI substitution in fish meal. The survival percentage after the bacterial challenge was increased by MSPI inclusion, the highest survival percentage was recorded in the MSPI66 group (95.55%) compared to MSPI0 (66.66%).MSPI22 increased the total return, net profit, and performance index %. It could be concluded that the maximum dietary replacement of fishmeal with MSPI Oreochromis niloticus fingerlings was 66%. The growth performance was decreased by increasing the substitution percentage of fish meal by MSPI. MSPI was shown to be a good immune-modulating substance and improved gut health. MSPI substitution at 88% is not recommended due to the bad effect on the hepatic and intestinal tissues.

Partial substitution of fish meal with soy protein concentrate in commercial diets for juvenile swimming crab, Portunus trituberculatus

A 56-day feeding trial was conducted to evaluate the potential use of soy protein concentrate (SPC) as a partial replacement of fish meal in swimming crab Portunus trituberculatus. Four isonitrogenous and isolipidic diets (450 g/kg protein and 80 g/kg lipid) were formulated to contain graded levels of SPC, and fish meal was replaced with SPC at 25%, 50% and 75% level (SPC25, SPC50 and SPC75, respectively). The control diet (SPC0) contained fish meal, soybean meal and krill meal as the main protein sources. Lysine and methionine were added into SPC replacement diets to maintain the same concentrations as the control diet. Each diet was randomly assigned to triplicate groups of 45 juvenile swimming crabs (5.00 ± 0.23 g / crab) that were stocked in the rectangle plastic baskets. The results indicated that the weight gain (WG), special growth rate (SGR), feed efficiency (FE) and daily feed intake (DFI) were not significantly influenced by the dietary replacement of fish meal with SPC (P > 0.05). Crabs fed the SPC75 diet had lower protein efficiency ratio (PER) and molting frequencey (MF) than those fed the SPC50 diet(P < 0.05). The proximate compositions in whole body and muscle were not significantly influenced by the replacement of fish meal with SPC (P > 0.05), however, there was significant difference in the hepatopancreas moisture content (P < 0.05), and crabs fed the SPC0 diet had the highest lipid in hepatopancreas among all treatments (P < 0.05). Moreover, the essential amino acid (EAA), non-essential amino acid (NEAA) and total amino acid (TAA) contents of muscle significantly increased with the dietary replacement of fish meal with SPC levels increasing from 0 to 75% (P < 0.05). No significant differences in hemolymph enzyme activities and characteristics were observed among all treatments (P > 0.05). Crabs fed the SPC0 diet had higher amylase and lipase activities in hepatopancreas than those fed other diets. The hepatopancreas trypsin activity was not significantly influenced by the replacement of fish meal with SPC (P > 0.05). The hepatopancreas alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities increased when the dietary SPC levels increased from 0 to 25%, and then decreased significantly with the further increase of SPC replacement levels (P < 0.05). The relative expression of genes in target of rapamycin (TOR) pathway, crabs fed the SPC0 diet had higher relative expressions of tor, akt, s6k1, s6, 4ebp1, eif4e1a, eif4e2 and eif4e3 genes in hepatopancreas than those fed other diets (P < 0.05), moreover, there were no significant differences in gene expressions of TOR pathway among crabs fed the SPC25, SPC50 and SPC75 diets (P > 0.05). Based on the two slope broken-line regression analysis of PER against the dietary fish meal replacement with SPC levels, the optimum dietary replacement of fish meal with SPC was determined to be 51.49% for juvenile swimming crab.