Fed Fish Meal Research Articles

Availability of Zinc, Copper, Iron, Manganese, and Selenium in Feed Ingredients and Sources in Pigs

This study evaluated the trace mineral availability of zinc (Zn), copper (Cu), iron (Fe), manganese (Mn), and selenium (Se) in major feed ingredients, including corn, wheat, soybean meal (SBM), and fish meal (FM). Additionally, we assessed the bioavailability of these minerals in pigs supplemented with inorganic, organic, and nano-sized forms prepared via hot-melt extrusion (HME). A total of 64 barrows (Yorkshire × Landrace × Duroc crossbreds) with an average initial body weight of 26.61 ± 4.12 kg were housed individually in metabolic cages. Pigs were allocated to eight experimental diets in a completely randomized design, with eight replicates per diet group. The apparent total tract digestibility (ATTD) of Zn and Cu was significantly higher in SBM and FM than in the other ingredients (p < 0.05). SBM exhibited higher ATTD and standardized total tract digestibility (STTD) for Fe and Mn than corn, wheat, and FM (p < 0.05). Corn and wheat demonstrated significantly greater digestibility of Se than SBM and FM (p < 0.05). Supplementation with nano-sized minerals prepared by HME increased the digestibility of Zn and Cu, as well as their concentrations in pigs’ serum and liver, while reducing the fecal excretion of these minerals (p < 0.05). Organic mineral forms significantly enhanced Se bioavailability, improving its digestibility and concentrations in the liver and pancreas compared to the inorganic form (p < 0.05). In growth performance, organic and nano-sized mineral sources significantly improved growth rate without the increase in feed intake (p < 0.05). In conclusion, Zn and Cu from high-protein ingredients such as SBM and FM were more digestible than those from grains. Furthermore, plant-based ingredients, such as corn, wheat, and SBM, exhibited greater digestibility of Fe and Se. Among the trace mineral sources, the organic and HME-nano forms improved the bioavailability of Zn, Cu, and Se, while reducing their fecal excretion, thereby enhancing the efficiency of mineral utilization.

Production Performance and Nutritional Quality of Black Soldier Fly Larvae Nurtured in Different Organic Waste

Nutritionists are beginning to pay attention to black soldier fly (Hermetia illucens L.) larvae (BSFL) as an alternative to expensive soybean and fish meal in animal feed which is abundant in different nutrients. Additionally, organic wastes including leftover food, animal excreta, and agricultural wastes, can be used to efficiently raise and spread BSFL. This study was carried out to evaluate the yield, production performance and proximate composition of BSFL nurtured on different organic waste namely, broiler starter feed (BF); rice bran (RB); market-sourced vegetable wastes (VW); chicken manure (CM) and kitchen waste (KW). The BF fed group had the highest observed larval yields (16.2 kg in total; P<0.05). Raising BSFL on BF, VW and KW resulted in the greatest body weight (0.149, 0.147 and 0.150 g, respectively) and growth rate (0.012 g), whereas the KW fed group had the longest body length (P<0.05). The fed groups that received CM and BF had the highest and lowest mortality rates, respectively (P<0.05). All fed groups except RB had improved feed conversion ratios, while VW and KW fed groups had higher protein conversion ratios (2.626 and 2.852, respectively; P<0.05). All the group had better substrate reduction rate compared to CM fed group (P<0.05). The dry matter and ash contents of BSFL reared on BF, VW and KW were higher than the RB and CM group (P<0.05). The KW supplemented BSFL had the highest ether extract level, whereas the BF fed group had the highest protein content (43.58%, P<0.05). In conclusion, BSFL can be successfully reared on kitchen and vegetable scraps. It is anticipated that the cost of black soldier fly farming and animal production will decrease since these organic waste shown favorable effects on BSFL growth performance and nutritional quality comparable to broiler feed in the current study. J. of Sci. and Tech. Res. 6(1): 139-148, 2024

Fishmeal intervention after short-term novel proteins stimulates compensatory growth and affects intestinal health in largemouth bass (Micropterus salmoides).

This research utilized a compensatory growth phenomenon aimed at reducing the use of fishmeal in aquatic animal feed. However, the compensatory growth triggered by fishmeal restriction with novel protein replacement has yet to be understood. Five isonitrogenous and isolipidic diets containing different proteins were manufactured, with fishmeal serving as the control and diets containing novel proteins, i.e., Chlorella (Chlorella vulgaris), cottonseed protein concentrate, Clostridium autoethanogenum, and yellow mealworm (Tenebrio molitor), serving as the experimental diets. Largemouth bass (Micropterus salmoides) with a starting body weight of 4.73 ± 0.04g were respectively fed these five diets for the first 29days (first stage), followed by a fishmeal diet for the remaining 29days (second stage). The diet of fishmeal, Chlorella vulgaris, cottonseed protein concentrate, Clostridium autoethanogenum, and Tenebrio molitor was referred to as FM, ChM, CSM, CAP, and TM, respectively. All novel protein groups showed a 60-73% higher weight gain compared to the fishmeal group during the second phase; however, they did not reach the weight level seen in the control group. In addition, the second stage of fishmeal intervention resulted in a reduction of approximately 35% in the area of positive Alcian blue (AB) staining of intestinal tissues in the CSM group, and about 40% in the CAP group, compared to the first stage. Furthermore, the area of intestinal apoptosis in TM was enlarged after fishmeal intervention while it was decreased in other experimental groups. At day 58, gene expression analysis of the CAP group fish at the end of the trial revealed increased levels of the anti-apoptotic gene bcl-2, as well as higher expression of intestinal inflammatory cytokines il-1β, tnf-α, nf-κb p65, and il-10, compared to the FM group. In terms of the biochemical indices, the levels of catalase (CAT) and glutathione peroxidase (GSH-Px) were reduced in CSM on day 58. An assessment of potential microbial function at end of trial demonstrated that CAP could reduce the lipid metabolism and amino acid metabolism, and increased carbohydrate metabolism pathways in the largemouth bass intestine. In conclusion, both CAP and ChM groups showed promise to reduce fishmeal with respect to intestinal health rather than growth. This study should be of value to practitioners wishing to use novel proteins to reduce fishmeal via the utilization of the compensatory growth phenomenon.

Interactions between feed protein source and feeding frequency on growth performance and health status of largemouth bass (Micropterus salmoides).

In order to evaluate the effects of the interaction between different proteins and feeding frequency on largemouth bass (Micropterus salmoides) and to provide scientific guidance for the application of novel proteins and the corresponding optimal feeding strategy, a two-factorial design (5 × 3) with five protein feeds (fishmeal (FM), Clostridium autoethanogenum protein (CAP), Tenebrio molitor (TM), Chlorella meal (ChM), cottonseed protein concentrate (CPC)), and three feeding frequency (1, 2, and 3 times/d; FF1, FF2, FF3) was designed in culturing largemouth bass (initial weight, 2.98 ± 0.22g/fish) for 8weeks. Z-score combined with cluster analysis was used to analyze and compare the effects of different treatments on different indicators, such as growth performance, feed utilization, antioxidant capacity, and immune response to draw a general picture of the relationship among all these massive biomarkers. The results showed that different protein sources and feeding frequencies had significant interactive effects on growth performance, feed utilization efficiency, body lipid, and health status of largemouth bass. Fish fed with ChM feed showed similar performance to that in FM group, implying its potential for complete replacement of fishmeal in largemouth bass. Fish fed with CAP, TM, and CPC feeds showed worse performance compared to FM and ChM groups, characterized by poor growth and feed utilization, enhanced stress, chronic inflammation, and varying symptoms of histological changes in the liver and intestine, which demonstrated the adverse effects of the complete replacement of fishmeal by these three proteins. In terms of feeding frequency, fish fed with FM feed in FF3 group led to liver hypertrophy, fat accumulation, and the risk of fatty liver, while inducing liver inflammation. In addition, the TM and CAP group had the higher expression levels of inflammatory factors at FF3 group, which displayed that the interactions between FM, CAP, TM feeds and feeding frequency at FF3 might aggravate the occurrence of liver inflammation and oxidative damage of hepatocytes. Overall, FF2 had higher feed efficiency, protein efficiency, antioxidant enzyme and lysozyme activities, lower MDA content, and lower gene expression of inflammatory cytokines and could be considered as the optimum feeding frequency for largemouth bass fed with different protein feeds.

Carp growth, body composition, lipidomics, and flesh quality in response to replacing dietary fish meal with a complex protein source

Alternatives to fish meal (FM) in fish feed are urgently required in aquaculture. We therefore examined the effect of replacing FM with a complex protein source (CPS) comprising soybean meal, peanut meal, corn protein meal, feather meal, and yeast protein, on carp (Cyprinus carpio) growth, body composition, lipidomics, and flesh quality. Lipidomics analysis was conducted to reveal the impact of dietary changes on fish lipid composition and metabolism, which is closely related to flesh quality and nutritional value. Over an eight-week growth trial, fish meal was replaced with CPS at 0 % (FM only), 20 %, 40 %, 60 %, 80 %, or 100 %. Weight gain and other growth parameters did not differ significantly among the treatments. Lipid deposition (LD) was positively correlated, and protein deposition negatively correlated, with CPS levels. LD and fillet ether extract were significantly elevated at 100 % CPS, whereas superoxidase dismutase expression, claudin-1 expression, and lipase activity were significantly reduced. The n-3 PUFA level and n-3/n-6 PUFA ratio were significantly lower following CPS feeding, reducing flesh quality. These findings indicate that CPS successfully replaced 60–80 % of dietary FM in carp diets, while the 100 % replacement group provided insights into the comprehensive effects of total substitution. Future studies will further optimize formulations based on these results to resemble practical production more closely. CPS with nutrient supplementation may therefore present a viable and safe partial replacement for dietary FM.

Towards cleaner environment: recycling microalgal co-product to reduce emissions and impacts while eliminating fishmeal in rainbow trout feed for sustainable aquaculture

The rapid increase in aquaculture over the last several decades has led to concerns about the environmental impact of fish feeds relying on marine resources for fishmeal (FM). We aim to assess Nannochloropsis sp. QH25 co-product as a viable and sustainable replacement for FM in juvenile rainbow trout, Oncorhynchus mykiss, feeds. We formulated four experimental diets: a reference (FM based), 33N, 66N, and 100N diet (33%, 66%, and 100% co-product replacement). Rainbow trout were randomly assigned to one of 16 tanks and randomly assigned an experimental diet to consume throughout the experiment (64 days total), with four replicate tanks per diet. We compared the phosphorus (P) and nitrogen (N) digestibility, emissions, and growth between diets and, compared six environmental impacts (biotic resource use (BRU), global warming potential (GWP), water use, land use, marine eutrophication potential (MEP), and freshwater eutrophication potential (FEP)) of each diet. Our results indicate that replacing FM with co-product did not significantly alter growth. P digestibility of the experimental and reference diets was comparable. BRU conversion ratio was significantly lower in the experimental diets. However, there were significantly higher water and land use conversion ratios but insignificantly higher results in GWP, MEP, and FEP between the reference and 100N diet.

Advantages of duckweed as a partial substitute for fishmeal in aquaculture feed

Advantages of duckweed as a partial substitute for fishmeal in aquaculture feed

A study on the effects of replacing fishmeal with soybean meal in the feed of Procambarus clarkii: Assessing growth performance, immunity, and gut microbiota

The unstable supply and high cost of fishmeal have led to increased interest in low fish meal feed. As such, the present study aimed to investigate the effects of replacing fishmeal in feeds with soybean meal (SM) on the growth, immunity, and gut microbiota of crayfish. A total of 750 crayfish (4.00 g) were randomly divided into five groups (SS0, SS25, SS50, SS75, and SS100) with three replicates, and were fed diets with different levels of soybean meal substituted for fishmeal for six weeks. The results revealed that crayfish subjected to high SM diets experienced a significant decrease in the final body weight, weight gain rate, and specific growth rate (p<0.05), together with enzyme activities related to nutrient digestion and absorption. Of note, the groups with 25–50 % SM replacement exhibited decreased final body weight without significance compared to that in the SS0 group (p>0.05). Moreover, increasing SM inclusion exhibited the potential to impair the intestine, characterized by the increase in hemolymph LD content, decrease in the levels of TC content, T-AOC, and AKP, along with the observed edema of the lamina propria, and up-regulated mRNA expression levels of nfkb, alf, and tlr. Furthermore, high SM diets resulted in the emergence of new species and a shift in Firmicutes, Bacteroidota, Proteobacteria, and Fusobacteriota. Specifically, the abundance of lower Firmicutes and higher Proteobacteria was observed in the SS100 group, which was closely correlated with genus-level Candidatus Bacilloplasma, and RsaHf231 abundance alterations. MENAs demonstrated that the high SM diets led to a more complex, yet fragile and unstable microbial network. The global network further indicated that the microbes contributing more to crayfish were in module eigen 4, in which 9 OTUs were identified as major biomarkers and mainly classified into Proteobacteria. Taken above, SM could replace 25 % of fishmeal in crayfish diets without negatively affecting growth performance, nutrient utilization, immunity, and antioxidant capacity. Excessive SM levels contributed to gut dysfunction and weakened the immune system of crayfish.

Assessing the Socio-Economic Benefits and Costs of Insect Meal as a Fishmeal Substitute in Livestock and Aquaculture

Sustainability targets set by the United Nations, such as Zero Hunger by 2030, encourage the search for innovative solutions to enhance food production while preserving the environment. Alternative protein sources for feed, while conventional resources like soymeal and fishmeal become more expensive and scarcer, is one of the possibilities. Studies on substituting fishmeal with insect meal show promising results in terms of animal growth and feed efficiency. This paper aims to assess the socio-economic benefits and costs of insect meal substituting fishmeal in feed and to highlight the factors influencing performance most. The study evaluates the economic value of insect-based products, waste reduction, and reduced greenhouse gas emissions as socio-economic benefits. It combines empirical data derived from laboratory trials and two case studies covering black soldier fly (Hermetia illucens) and yellow mealworm (Tenebrio molitor). Current analyses reveal negative socio-economic balances, emphasizing that reduction of operating and investment costs through upscaling and technological advancements can give a positive move, as well as factors such as current market valuations for nutrients can change significantly. Thus, a negative balance at the moment does not mean that insect rearing, and larva processing are not desirable from a long-term socio-economic perspective.

Suitable Cottonseed Protein Concentrate Supplementation in Common Carp (Cyprinus carpio) Serves as an Effective Strategy for Fish Meal Sparing Based on Improvement in Intestinal Antioxidant Capacity, Barrier and Microbiota Composition.

The application of cottonseed protein concentrate (CPC) is an effective strategy to moderate the shortage of fish meal (FM) for the aquafeed industry. However, little attention has been paid to the effects of replacing fishmeal with CPC on cyprinid fish. This study used common carp (Cyprinus carpio) as the biological model and assessed the potential of applying CPC as a substitute for fishmeal in the diet of common carp. The proportion of fish meal substituted with CPC in the six diets was 0% (CPC0), 25% (CPC25), 50% (CPC50), 75% (CPC75), and 100% (CPC100). Each diet was fed to three replicate groups of common carp (4.17 ± 0.02 g) for 56 days. Results revealed that the CPC50 group significantly increased the growth indexes via up-regulating the genes of the GH/IGF axis and the TOR pathway. The intestinal digestive ability was also elevated in the CPC50 group via markedly increasing intestinal villus height, protease and lipase activities in the whole intestine, and the amylase activity of the foregut and midgut. The CPC50 group captured significantly higher activities and gene expressions of antioxidant enzymes and lower malonaldehyde contents via evoking the Nrf2/Keap1 signal pathway. The CPC50 group enhance the intestinal mechanical barrier via up-regulating the gene expressions of tight junction proteins and heighten the intestinal biological barrier by increasing the probiotics (Lactococcus) and decreasing the harmful bacteria (Enterococcus). But excessive substitution levels (75% and 100%) would compromise growth performance, intestinal antioxidant capacity, and immune function. The optimum substitution level was estimated to be 46.47%, 47.72%, and 46.43% using broken-line regression analyses based on mass gain rate, protein efficiency ratio, and feed conversion rate. Overall, the fishmeal in common carp feed could be substituted up to 50% by CPC without negative influence on growth, feed utilization, and or intestinal health.

Advantages of duckweed as a partial substitute for fishmeal in aquaculture feed

Advantages of duckweed as a partial substitute for fishmeal in aquaculture feed

Effect of dietary phytase and protease supplementation on the growth performance and apparent nutrient digestibility in juvenile Pacific white shrimp (Litopenaeus vannamei) fed fish meal–free and phosphorus limiting diets

Effect of dietary phytase and protease supplementation on the growth performance and apparent nutrient digestibility in juvenile Pacific white shrimp (Litopenaeus vannamei) fed fish meal–free and phosphorus limiting diets

Toward sustainable food systems: can spirulina (Arthrospira platensis) become a sustainable source of protein to enhance the nutritional benefits of cultured Nile tilapia (Oreochromis niloticus)?

Hunger affected 278 million people in Africa in 2021, and in Kenya, the proportion of the population unable to afford a healthy diet is 81%. To combat hunger and increase resilience throughout the food system, spirulina (Arthrospira platensis) has been shown to have remarkable properties. The main aim of this study is to investigate whether protein from spirulina is a suitable alternative to protein sourced from fish meal in fish feed for juvenile Nile tilapia (Oreochromis niloticus). In a trial investigating the use of spirulina biomass for fish feed on juvenile Nile tilapia, it has been proven that tilapia fingerlings fed diets with spirulina, replacing up to 30% of fish meal protein, were not affected in terms of growth performance compared to the fish fed the commercial diet. This shows that, nutritionally, protein from spirulina can replace fish meal protein fed to juvenile Nile tilapia. This offers promising opportunities for enhanced food and nutrition security. If produced affordably, spirulina can have a significant impact on the income level of low-income fish farmers in Kenya, who often spend more than 50% of their income on commercial fish feed. Affordability can be made possible if small-scale farmers can produce spirulina using animal manure that is available on the farm instead of using highly priced commercial fertilizer. The additional environmental benefits of spirulina include carbon dioxide sequestration and the removal of nitrogenous and phosphorous waste from the wastewater. Spirulina can therefore increase the sustainability of a whole food system.

Immunobiotic potential of fermented snail meat hydrolysate in local chicken with low protein content.

Protein is needed for chicken growth, but high protein consumption causes a low protein efficiency ratio and causes feed prices to be expensive. Therefore, the immunological potential of fermented snail meat hydrolysate in local chickens was studied for feed supplements in low-protein rations to reduce costs. The research used snail meat hydrolysate resulting from submerged fermentation with starter culture from rice washing water. Using hydrolysates as a fishmeal substitute to reduce the protein content of male local chicken diets. Hydrolysate is mixed into the formulated ration: P0 = 12% fish meal in feed without hydrolysate added, P1 = 8% fish meal in feed plus 5 ml hydrolysate/kg feed; P2 = 4% fish meal in feed plus 10 ml hydrolysate/kg feed; and P3 = Feed without fish meal plus 15 ml hydrolysate/kg feed. The study used completely randomized study parameters, namely the production performance of 200 chickens and the immune system (including lymphoid organs and hematological status) of 60 chickens. Snail meat hydrolysate (10 ml/kg) can replace the reduction in the use of fish meal from 12% to 4% in ration formulation without reducing production performance and has no negative effect on the immune system. Snail meat hydrolysate has the potential to be used as an immune antibiotic to replace the use of fishmeal in the development of low-protein dietary formulations without affecting production performance or negatively affecting the chicken's immune system.

Effect of extrusion on energy and nutrient digestibility of lentil-based diets containing either supplemental plant or animal protein fed to growing pigs.

Non-food grade and excess lentil grain production may be included in swine feeds to provide starch and protein and reduce feed cost. Extrusion processing may increase energy and nutrient digestibility of lentil-based diets containing either supplemental plant or animal protein sources. Therefore, the apparent ileal digestibility (AID) of crude protein (CP) and amino acids (AA), apparent total tract digestibility (ATTD) of gross energy (GE), and digestible energy (DE) value of lentil-based diets were assessed in growing pigs. Two diets were formulated to provide 2.4 Mcal net energy (NE)/kg and 4.35g standardized ileal digestible lysine/Mcal NE: (1) soybean meal (SBM) diet, containing 50% lentil, 31% wheat, and 12.8% SBM; and (2) fish meal (FM) diet, containing 40% lentil, 45% wheat, and 10% FM. Following mixing, each diet batch was divided into two parts: one part remained as mash, whereas the other part was extruded using a single-screw extruder (400rpm, 250kg/h). Eight ileal-cannulated barrows (32.3 ± 1.5kg) were fed the four diets at 2.8 times maintenance DE requirement (110 kcal per kg of body weight0.75) for four 9-d periods in a double 4 × 4 Latin square to achieve 8 observations per diet. Data were analyzed as a 2 × 2 factorial arrangement including protein source, post-mixing processing, and their interaction as fixed effects. The lentil sample contained 32.3% starch, 24.4% CP, 9.3% total dietary fiber, and 1.7mg/g of trypsin inhibitor activity on as is-basis. Interactions between dietary protein source and post-mixing processing were not observed. Feeding FM diets resulted in greater (P < 0.05) AID of dry matter (DM), GE, and most AA, and ATTD of CP, but lower apparent hindgut fermentation of DM and GE than SBM diets. Extrusion increased (P < 0.05) the ATTD of GE and DE value of diets. The AID of CP and AA was 3.2 and 4.7%-units greater (P < 0.05), respectively, for the extruded than mash diets. In conclusion, feeding FM diets resulted in greater ileal digestibility of DM, GE, and AA than SBM diets. Extrusion increased the AID of CP and most AA, and DE value of lentil-based diets containing either supplemental plant protein or animal-protein, indicating that extrusion can increase the energy and protein value of plant-based diets fed to pigs.

Per- and poly-fluoroalkyl substances in commercial organic eggs via fishmeal in feed

Chicken eggs can be a significant source of human PFAS exposure. A survey of PFAS in commercial eggs from larger farms across Denmark showed the absence or low contents of PFAS in free-range and barn eggs. However, organic eggs from eight farms collected in September 2022 had a similar profile of nine PFASs with a predominance of odd over even carbon length PFCAs. Farm 11–13 e.g. had egg yolk ng/g concentrations of PFOA 0.07 ± 0.02; PFNA 0.37 ± 0.04; PFDA 0.13 ± 0.00; PFUnDA 0.22 ± 0.04; PFDoDA 0.06 ± 0.02; PFTrDA 0.15 ± 0.04; PFTeDA 0.02 ± 0.02; PFHxS 0.10 ± 0.04; PFOS 2.62 ± 0.11. Normalised to PFOS, the relative sum of other PFAS showed no difference between the eight organic egg samples, but significant differences between mean individual PFASs (p = 1.4E-25), reflecting a similar profile. The PFAS found in two fishmeal samples with the same origin as the fishmeal used for the organic feed production, could account for the contents in the eggs via estimated transfer from the feed. Furthermore, the estimated transfer from concentration in feed to concentration in egg increased with the carbon length of the PFCA. Exposure (95th percentile) of ∑4PFAS (PFOA, PFNA, PFHxS, PFOS) solely from consumption of 311 g ∼ 5–6 organic eggs/week was for children 4–9 years 10.4 ng/kg bw, i.e. a significant exceedance of the tolerable weekly intake of 4.4 ng/kg bw established by the European Food Safety Authority. Based on the PFAS exposures from organic egg consumption, the organic egg producers decided voluntarily to cease adding fishmeal to the feed. Since the feed-to-egg half-lives are ≤1 week for PFOA, PFOS, and PFHxS, the removal of fishmeal as a feed ingredient should eliminate PFAS after 1–2 months. This was demonstrated in analyses of ten organic egg samples collected by the authorities without PFAS in eight and with 0.1 and 0.4 ng/g ∑4PFAS in two samples.

Efficacy of an Insect-Based Diet with Addition of Probiotics on Growth, Proximate Composition, Enzymatic Efficiency, and Immune Response of Nile Tilapia

Insects are potential alternative protein sources to replace fish meal (FM) in aqua feed. The role of insect species as replacements in the aqua industry has been a hot debate in the current era. The present study evaluated the influence of FM replacement with insect-based meals (black soldier fly (BSF) and maggot fly) in the feed of Nile tilapia. Eight diets with graded replacement levels of FM were formulated along with basal diet as T0 (control group having basal diet), T1 (25% maggot meal (MM) with 2% probiotics), T2 (50% MM + 2% probiotics), T3 (75% MM + 2% probiotics), T4 (100% MM + 2% probiotics), T5 (25% BSF meal (BSFM) + 2% probiotics), T6 (50% BSFM + 2% probiotics), T7 (75% BSFM + 2% probiotics), and T8 (100% BSFM + 2% probiotics). Fish having an initial body weight of 7 g were fed on formulated feed for 16 weeks. Growth parameters, including weight, length, feed conversion ratio, specific growth rate, and survival rate, were observed weekly, and significant ( p &lt; 0.05 ) results were attained up to 75% replacement level with no adverse effect on growth. However, at 100% replacement of FM, fish growth was retarded. Maximum survival rate was observed in T1 and T5 and minimal in T4 and T8. Body composition, including crude protein, fat, moisture, and ash, showed significant ( p &lt; 0.05 ) results. Similarly, digestive enzyme (protease, lipase, and amylase) activity was measured at the end of the trial. Fish in T1 and T5 groups had the highest digestive enzyme activity, which slightly decreased with the inclusion of insect-based meals and probiotics. Statistically significant ( p &lt; 0.05 ) results were observed for antioxidant enzyme activity in catalase, glutathione peroxidase, and superoxide dismutase. The most vigorous immune response was shown in T1 and T5, with higher white blood cells and high levels of IgM. The present research showed that FM could be replaced with BSF meal and MM with probiotics up to 50% for better fish health performance; however, 75% replaced FM without compromising growth and health status.

Effect of Replacing Fish Meal by Soybean Meal on the Performance, Nutrient Utilization and Egg Quality of Khaki Campbell Ducks in Late Laying Phase

Background: Feed quality in terms of protein source plays an important role in achieving targeted production. The quality of fish meal available in market is of highly variable in nature. Hence, an attempt was made to see the response of laying ducks to diets where fish was replaced by soybean meal with supplementation of critical aminoacids i.e. lysine and methionine over and above the normal requirement. Methods: A 16 week biological trial consisting of 72 Khaki Campbell laying ducks (83 weeks) subjected to three treatments (T1-Control diet with fish meal, T2- fish meal totally replaced by soybean meal, T3-T2 + Supplementation of Lysine and Methionine distributed equally to 9 replications of 8 laying ducks each was conducted following completely randomised design to see the effect of treatments on the performance, nutrient digestibility/retention and egg quality in Khaki Campbell laying ducks. Standard analytical and statistical procedures were followed for proper interpretation of the data. Result: The egg production (nos and dozen) and DDEP percent were significantly (P less than 0.05) higher and FCR was significantly (P less than 0.05) better for ducks reared on T1 compared to other groups. The dry matter, organic matter and crude fibre digestibility was significantly (P less than 0.05) higher for ducks fed fish meal. However, the EE digestibility was significantly (P less than 0.05) higher for T3 group. The egg quality parameters were significantly higher for T3 group. It is concluded that the performance of Khaki Campbell laying ducks fed diet without fish meal was deteriorated but the egg quality was improved.

Crickets (Gryllus Bimaculatus) using food waste usefulness of self-selection feed design method through each growth stage

Abstract In this study, a self-selected feed design was conducted for Japanese food wastes, considering the macronutrients (protein, lipid, carbohydrate) and six feed options and three options for vegetable wastes, and performance was compared with commercial diet to determine the usefulness of the feed design method and the possibility of using food waste in Japan were examined by comparing the performance of the feed design method with commercial diet. Data on self-selection diet design for crickets at different growth stages were obtained to determine the differences in feed consumption rates and nutrient requirements among stages. The results showed that it is possible to achieve cricket weight and feed conversion efficiencies (0.5-0.8) comparable to those of commercial diets using food residues when macro-nutrients are considered, and abundant options are provided. On the other hand, the use of only vegetable wastes resulted in lower cricket weight and higher feed conversion efficiency (0.8-1.4). Based on feed consumption rates, bread bran, rice bran, and fish meal were found to be suitable feeds among Japanese food waste for production in all growth stages, while bean curd and sake less were found to be suitable for production in some growth stages. Data obtained from self-selections separated by growth stage revealed that the percentage of feed consumption varied greatly among growth stages, being about 50-68% in the late growth stage. Percentages of macronutrients and micronutrients were also found to vary by growth stage. Protein percentages were found to be higher in the second week after hatching. Lipids were highest in the first week and decreased thereafter. Crude fiber was lowest in the fourth week. Ash content did not change significantly at all stages. This research is the first attempt at self-selection of crickets in different growth stages, and the data obtained can contribute to feed design.

Influence of genetic adaption of rainbow trout (Oncorhynchus mykiss) fed with alternative protein sources based on Arthrospira platensis and Hermetia illucens on intestinal health and animal welfare

Genetic adaptation to new environmental conditions, such as changing diets, has always played a key role in the evolution of animals. Fish, in particular, have a great genetic potential for adaptability to regional environmental demands. Feeding diets devoid of marine resources to carnivorous fish species is paramount to enable fully sustainable aquaculture and independence of capture fisheries. Therefore, novel sources of protein substituting fishmeal in fish feed are of increasing interest in aquaculture. However, the use of plant-based protein sources in the diet of carnivorous fish is in controversial discussion because of their association with several issues related to food conversion, growth rate, fish health and welfare effects. The current study aims at making use of the genetic variability of rainbow trout (Oncorhynchus mykiss) in order to gain new insights into their adaptability to innovative raw materials with a particular focus on the question of how the replacement of fishmeal by Arthospira platensis and Hermetia illucens in fish feed affects the intestinal health. Therefore, 20% fishmeal of the total composition was completely replaced in each case with Arthrospira platensis or Hermetia illucens. The results showed that the stress response, investigated by analysing the concentration of heat shock protein 70 in liver samples, proved to be at very low values for all investigated groups. A chronic stress exposure due to the supplementation could thus be excluded. Regarding growth, the genetic background played a decisive role. Despite morphological and histological changes in the anterior intestine of experimental feeding groups, no negative influence on growth could be detected. A significantly higher expression of occludin in the posterior intestine of the Arthrospira groups with respect to the epithelial barrier was noted. Altogether, no signs of cell infiltration were detected in the intestines of the animals despite the Arthrospira fed groups and one Hermetia fed group showing partially significantly higher gene expressions according to IL1β, TNFα and singular antimicrobial peptides than fish from other feedings. Therefore, the current study reveals that supplementing the fishmeal portion of rainbow trout diets with Arthrospira platensis or Hermetia illucens does not negatively affect fish health and animal welfare.