Replacement Of Fish Meal Research Articles

Fishmeal substitution by zooplankton or Daphnia magna biomass meals in the diet of Nile tilapia: Effectson growth, gut histological changes, bacterial abundanceand stress tolerance.

Fishmeal substitution with sustainable feed sources is highly essential towards sustainable production. This study aimed to investigate the effects of substituting fishmeal (FM) with Daphnia magna biomass meal (DBM) or zooplankton biomass meal (ZBM) on growth performance, liverand intestinal histology, gut bacterial abundanceand stress tolerance of Nile tilapia, Oreochromis niloticus, fry. Nile tilapia fry (0.23 ± 0.04 g) were randomly assigned to five groups of three replicates. The control diet comprised 300 g/kg FM, and the FM was substituted with DBM or ZBM at levels of 25% and 50% (DBM-25, DBM-50, ZBM-25and ZBM-50respectively) in the other experimental diets. The experiment lasted 56 days in 1.5 m3 concrete tanks. The results revealed that weight gain andfeed conversion ratio(FCR) significantly (p ≤ 0.035 and 0.025respectively) improved with a polynomial response with a peak at 25% ZBM and a linear increase with DBM up to 50% of FM. Histometric indices of the distal intestine showed improvements (p ≤ 0.001) in villus height, villus width, crypt depthand muscle thickness of fish fed DBM or ZBM compared to the control. In the meantime, there were no histological abnormalities in the liver sections. The replacement of FM with DBM or ZBM could modulated gut bacterial abundance, including total bacterial count, Escherichia coli, Bacillus subtilis, and Lactobacillus sp. The fish-fed DBM or ZBM-containing diets had higher (p ≤ 0.05) tolerances to salinity stress than the control group. In conclusion, DBM or ZBM could replace FM up to 50% and 25%, respectivelywith improved fish growth performance, FCR, gut histologyand tolerance to salinity stress.

Partial Replacement of Fishmeal with Seafood Discards for Juvenile Penaeus japonicus: Effects on Growth, Flesh Quality, Chemical and Fatty Acid Composition

The present study was designed to assess the influence of fishmeal replacement with increasing percentages of fresh seafood discards (0, 25, 50 and 75%) in diets for Penaeus japonicus on growth performance, physical characteristics and the chemical and fatty acid composition of shrimp flesh. Each diet was administered for 108 days, and the trial was assayed in triplicate. The final body weight and the specific growth rate were significantly higher (p < 0.05) in shrimps fed with 75% fishmeal replacement as compared to 25%, while the abdomen weight and the total length were the highest (p < 0.01). Moreover, 75% replacement showed a significantly (p < 0.05) lower value of hardness and a greater crude protein and lipid content as compared to the 0% replacement. The shrimps fed with high levels of seafood discards (50 and 75%) showed a lower saturated fatty acid concentration and, in turn, a greater amount of polyunsaturated fatty acids in shrimp meat significantly (p < 0.05) affected the lower atherogenic and thrombogenic indices. In conclusion, replacing 75% of fishmeal with seafood discards provided satisfactory results. An economic analysis based on ESG indicators and PESTLE methodology is provided in order to show the socio-economic and governance impacts affecting the replacement of shrimps’ diet with fish discard.

Studying the efficiency of Gaprin application in sterlet farming

In the course of the experiment, the influence of new feed additives created on the basis of Gaprin and representing biomass of inactivated cell culture of non-pathogenic methane-oxidizing yeasts or bacteria on sturgeon fish productivity indicators was studied. The research was carried out in the Krasnodar Territory on sterlet fingerlings. The experiment lasted for 60 days. According to the scheme of the experiment, the 1st (control) group of fish received complete feeds without additives, i.e. containing 100.0% fish meal. In group 2 feeding, 50.0% fishmeal was replaced with 50.0% Gaprin. Group 3 diet contained 25.0% fishmeal and 75.0% Gaprin. In the feed for group 4, fish meal and Gaprin were in the ratio of 75/25%. In Group 5, fish meal was completely replaced by Gaprin, in this case the amount of additive was 10.5 kg. Sterlet fingerlings from Group 6 received feed with 10.0% Gaprin. The initial live weight in all groups was similar at 30 g. However, the inclusion of Gaprin in the diet by reducing the amount of fish meal contributed to an increase in the final live weight of sterlets in the experimental groups by 4.4–19.4% compared to the control. The exceptions were groups 5 and 6, which received 100.0 and 90.0% Gaprin instead of fishmeal. Final live weight in these groups was lower by 2.3 and 0.9%, respectively. Feed costs per 1 kg of live weight gain in the groups with partial or complete replacement of fish meal were lower relative to the 1st group (from 7.0 to 17.9%,).Inclusion of Gaprin in complete feeds contributed to the increase in profit from 553.00 to 1785.00 rubles.

The effect of fishmeal replacement with organic acid fermented black soldier fly (Hermetia illucens) larvae meal on growth, nutrient utilization, metabolic enzyme activity, antioxidant status and immunity in Pangasius (Pangasianodon hypophthalmus)

Black soldier fly (Hermetia illucens) larvae meal is emerging as an alternative protein source and good substitute of fishmeal (FM). In an 8-week feeding trial, three hundred pangasius (Pangasianodon hypophthalmus,7.44 ± 0.01 g) fingerlings were randomly allocated over five treatments in triplicate tanks and fed five isoprotein (CP, 35%) and isolipidic (CL, 10%) diets formulated by replacing 0% (FBSFL0), 25% (FBSFL25), 50% (FBSFL50), 75% (FBSFL75) and 100% (FBSFL100) FM with organic acid (formic acid) fermented black soldier fly larvae meal (FBSFL). The inclusion of FBSFL did not affect growth, feed conversion ratio, nutrients utilization and survival rate of pangasius even when FM was completely replaced. The pangasius body protein content increased significantly (P < 0.05) with increasing FBSFL level in the diets while, body lipid content was unaffected (P > 0.05). The haematological indices were not (P > 0.05) affected with the FBSFL inclusion levels. Significantly (P < 0.05) higher and alike protease activity was recorded in FBSFL50, FBSFL75, and FBSFL100 groups. However, activity of amylase and lipase were similar among treatments. The liver antioxidant enzymes (SOD, catalase, and GST) did not show significant (P > 0.05) difference among the treatments. However, pangasius fed with FBSFL75 and FBSFL100 showed significantly higher and similar total antioxidant capacity (T-AOC). The FBSFL in the diet of pangasius did not affect the liver metabolic enzyme (MDH, G-6-PDH and GDH) activities. Relative gene expression of growth hormone (GH1) did not substantially differ among the groups (P < 0.05). No differences were observed in the immune gene expressions of complement (C3) and interleukin-1β (IL-1β) but the expression level of transferrin was up-regulated significantly (P < 0.05) in FBSFL25 group. No damage was observed in hepatic tissues in histomorphometry examination due to the inclusion of FBSFL. The study concludes that formic acid fermented BSFL can be employed as a complete substitute for FM in the pangasius diet, offering additional health benefits without any adverse effects.

Earthworm, Perionyx excavatus as an alternate protein source for Nile tilapia: Effects on growth performance, blood biochemistry, erythrocyte morphology and intestinal health

Recently, an increasing disparity has emerged in the need for raw fish meal (FM) and its supply, along with the environmental and financial obstacles associated with its use. Therefore, increasing and elevating the diversity of alternative protein sources for aquaculture nutrition is imperative. The study investigated the impact of substituting FM protein with EW meal on the growth, haemato-biochemical response and intestinal histomorphology of Nile tilapia. Up to 20% fishmeal replacement with EW meal had no adverse effects on fish growth performance. A quadratic analysis of the final body weight and EW meal level indicated the best growth performance at 17.5% replacement. Fish fed the 40% replacement level had significantly decreased height and width of intestinal folds and number of mucosal goblet cells compared to the control. Although red and white blood cell counts were found unchanged between the control, the 10% and 20% replacement groups, a significantly higher number of white blood cells and a lower number of red blood cells were found in the 40% group compared to the control. Blood glucose level was the highest, while haemoglobin level was the lowest in the 40% group. In the same group, significantly higher frequencies of erythrocyte cellular and nuclear abnormalities were noted. Lipid droplet accumulation in the liver was significantly higher in the 40% group, whilst the 10% and 20% groups showed no significant difference compared to the control.

Physiological Response of European Sea Bass (Dicentrarchus labrax) Juveniles to an Acute Stress Challenge: The Impact of Partial and Total Dietary Fishmeal Replacement by an Insect Meal

This study aimed to explore the effect of FM substitution by defatted Tenebrio molitor larvae meal (dTM) on the response of European seabass to an acute stress challenge. An FM-based diet was used as a control and two other isoproteic/isoenergetic diets were formulated to replace 50 and 100% of FM by dTM. Each diet was tested in quadruplicate groups of 15 fish (69 ± 5 g) fed until visual satiety for 16 weeks. After the feeding trial, fish were subjected to 1 min air exposure followed by 1 h of recovery before sampling. The haematological profile, plasma metabolites, and humoral immunity biomarkers, as well as hepatic oxidative stress and antioxidant capacity, were analysed. A clear response to acute stress was observed by a significant increase in haemoglobin, haematocrit, red blood cells, and almost all evaluated plasma metabolites and humoral parameters, regardless of dietary treatment. The obtained results demonstrated that partial substitution of FM by IM did not affect the stress response of seabass. However, total FM replacement increased the hepatic activity of total peroxidase and superoxide dismutase in fish fed TM100.

A biofloc system avoids the adverse effects of diets with suboptimal protein levels on zootechnical performance, intestinal histomorphometry, and protein metabolism of Nile tilapia juvenile fed Spirulina biomass (Arthrospira platensis) as an alternative protein source.

This study aimed to evaluate the effect of the biofloc technology (BFT) system and the replacement of fish meal with Spirulina biomass on productive performance, intestinal histomorphometry, plasma biochemistry, and oxidative stress of Nile tilapia juveniles (Oreochromis niloticus) fed suboptimal levels of protein. Two factors were evaluated: production systems (clear water × BFT) and replacement of fish meal with Spirulina (0, 33, 66 e 100%). The design was in a 2 × 4 randomized factorial scheme with four replications, and the fish were evaluated for 48days. Four isoproteic (28% crude protein) diets were formulated with gross energy values close to 4300kcalkg-1. Nile tilapia juveniles (0.23 ± 0.01g) were distributed in 16 circular tanks (70 L) at seven fish/tank. The diets were formulated with protein levels approximately 20% below that required for the species and life stage. No interaction was observed between the factors evaluated (production systems × Spirulina inclusion). Rearing the fish in the BFT system avoided the adverse effects of diets with suboptimal protein levels on performance, intestinal histomorphometry, and protein metabolism. Lower values lower lipid peroxidation and higher antioxidant capacity were observed in fish reared in the BFT system, showing evidence of improvements in antioxidant responses and lower levels of physiological oxidative stress. Spirulina completely replaced fish meal in the diets of Nile tilapia juveniles without adverse effects on intestinal morphometry, protein metabolism, and antioxidant response. Replacing 66% of fish meal with Spirulina improved the productive performance, regardless of the rearing system.

Apparent and True Digestibility in Clarias gariepinus, Burchell, 1822 FED Soyabean Meal Based Diets Supplemented with Protease

Soyabean meal (SBM) could be a suitable replacement for the expensive fishmeal but for its low digestibility in fish. However, protease supplementation could improve digestibility of SBM based diets. Therefore, apparent and true digestibility in Clarias gariepinus fed SBM based diets supplemented with protease were investigated. Six diets containing varied inclusion levels of protease (ppm) in solvent extracted soybean-based diets (SESBD) were formulated; Control (without protease), SS100 (100), SS200 (200), SS300 (300), SS400 (400), SS500 (500). The Clarias gariepinus (n=720) weighing 12.00±0.10g were fed to satiation with the diets for 12 weeks. Each treatment was in triplicate. Protease supplementation significantly (P&lt;0.05) influenced the weight gain of C. gariepinus with the higher value in fish fed SS400 (44.63±3.13) and least value in control diet (32.03±0.65). FCR had a significantly (P&lt;0.05) least value in C. gariepinus fed SS400 (1.62±0.18) but similar (P&gt;0.05) to C. gariepinus diet SS300 (1.88±0.11). Supplemental protease in soyabean-based diet improved (P&lt;0.05) apparent protein digestibility of C. gariepinus on diet SS400 (87.38±1.10) but similar (P&gt;0.05) to C. gariepinus on diet SS200 (87.29±0.97). Also, true lysine digestibility was enhanced with protease supplementation in soybean-based diet with the higher value in diet SS200 (95.90±0.07). Optimal FCR occurred SESBD of 350ppm dietary inclusion (R2= 0.8147) of protease. The findings suggest that, protease supplementation in solvent extracted soyabean based diet could improve growth performance and amino acid digestibility in C. gariepinus at 350ppm inclusion level.

Dietary fishmeal replacement by Clostridium autoethanogenum protein meal influences the nutritional and sensory quality of turbot (Scophthalmus maximus) via the TOR/AAR/AMPK pathways

Clostridium autoethanogenum protein (CAP) is a promising protein source for aquaculture; however, how CAP influences fish quality is worth extensive research. We randomly allocated 630 turbot with initial body weights of about 180 g into 6 groups, with fishmeal-based control diet or diet with CAP replacing 15% (CAP15), 30% (CAP30), 45% (CAP45), 60% (CAP60), or 75% (CAP75) of fishmeal protein. After a 70-d feeding trial, the fillet yield (P = 0.015) and content of protein (P = 0.017), collagen (P < 0.001), hydroxyproline (P < 0.001), C20:5n-3 (P = 0.007), and ∑n-3/∑n-6 polyunsaturated fatty acids ratio (P < 0.001) in turbot muscle was found to decrease linearly with increasing CAP. However, turbot fed CAP15 diet maintained these parameters (P > 0.05). By contrast, the muscle hardness increased linearly with increasing CAP (P = 0.004), accompanied by linear reduction of muscle fiber area (P = 0.003) and expression of myogenesis-related genes, including cathepsin D (ctsdP < 0.001) and muscle ring finger protein 1 (murf 1, P < 0.001). Phosphorylation of protein kinase B (Akt, P < 0.001), target of rapamycin (TOR, P = 0.001), eukaryotic initiation factor 4E-binding protein 1 (4E-BP1, P < 0.001), and ribosomal protein S6 (S6, P < 0.001) decreased linearly; however, phosphorylation of AMP-activated protein kinase (AMPK, P < 0.001), eukaryotic initiation factor 2α (eIF2α, P < 0.001), and the abundance of activating transcription factor 4 (ATF4, P < 0.001) increased with increasing CAP, suggesting that the TOR signaling pathway was inhibited, and the amino acid response (AAR) and AMPK pathways were activated. Additionally, expression of genes related to protein degradation, including myogenic factor 5 (myf 5, P < 0.001), myogenic differentiation (myod, P < 0.001), paired box 7 (pax 7, P < 0.001), and ctsd (P < 0.001), decreased linearly with increasing CAP. In conclusion, CAP could be used to replace up to 15% of fishmeal without negatively impacting turbot quality. However, higher levels of CAP decreased fillet yield, muscle protein content, and muscle fiber diameter while increasing muscle hardness, which could be attributed to the inhibition of the TOR pathway and activation of the AAR and AMPK pathways.

Partial Replacement of Fishmeal with Black Soldier Fly Larvae Meal in Nile Tilapia Diets Improves Performance and Profitability in Earthen Pond

Insect meals have the potential to be used as a source of nutrients in aquafeeds due to their high nutritional profile and cost effectiveness. The objective of this study was to elucidate the impact of black soldier fly larvae meal (BSFLM) as a replacement for fish meal (FM) on Nile tilapia (Oreochromis niloticus, L) growth performance, survival rate, somatic indexes and economic benefits. Four experimental diets were prepared; three with BSFLM as a substitute for FM at 25 % (T25 %), 50 % (T50 %) and 75 % (T75 %) and a control diet without BSFLM (T0 %, 100 % FM). A total of 360 fingerlings weighing about 20 - 30 gs each were assigned to twelve cages built in a 720m2 earthen pond, with 30 fingerlings in each cage in a completely randomized design with three replications in each treatment group. The fingerlings were fed the experimental diets for 26 weeks. The results showed that the treatment diets did not significantly affect body weight gain and daily feed intake (p > 0.05). However, treatment T50 % (52.16 g) had the highest body weight gain while treatment T75 % (46.00 g) had the lowest body weight gain even though not statistically different (p > 0.05). The body length also followed the same trend being higher in T50 % (16.50 cm) and lowest in T75 % (15.91 cm). The survival rate was significantly influenced (p < 0.05) by the diet treatment groups, while blood parameters, visceral somatic and hepatosomatic indexes did not vary significantly (p > 0.05) across the treatment diets. Return on investment and the cost-benefit ratio were significantly (p < 0.05) affected by the partial replacement of FM with BSFLM. Diets T25 %, T50 % and T75 % had higher (p < 0.05) profit margins when compared with diet T0 % (control). The study found that BSFLM can replace FM in diets for Nile tilapia without compromising on the growth performance of the fish while also increasing the profitability.

Effects of replacing fish meal with biofloc meal on growth performance, nutrients metabolism, immune response and intestinal microbiota of common carp (Cyprinus carpio)

This study investigated the effects of replacing fish meal (FM) with biofloc meal (BM) on the growth, digestion function, protein metabolism, lipid metabolism, immunity, antioxidant capacity and intestinal microbiota of common carp (Cyprinus carpio). The experiment includes two trials (a growth trial and a digestibility trial). In the growth trial, the control diet contained 20% FM. And five isonitrogenous and isolipidic diets were formulated to replace 0% (CK), 20% (BM20), 40% (BM40), 60% (BM60) and 80% (BM80) of the FM protein with BM. The five diets were fed to common carp (3.73 ± 0.01 g) for 56 days. The results indicated that the growth performance [final weight (FW), specific growth rate (SGR) and feed efficiency ratio (FER)] and digestive enzymes activities displayed a noteworthy quadratic trend with the increasing replacement level of FM with BM (P < 0.05), reaching a maximum at the BM40 group and a minimum at the BM80 group. Regression analysis of weight gain rate (WGR) against the substitution level found that the optimal level of BM replacing FM was 34.12%. The appropriate levels of BM could improve protein metabolism and lipid metabolism by regulating the expressions of related genes. Regarding the expression levels of PI3K, mTOR and HSL mRNA, they were the highest in the BM40 group and the lowest in the BM80 group, while the levels of ACC and FAS mRNA were reversed (P < 0.05). Simultaneously, the number of lipid vacuoles in the BM80 group were significantly increased than the CK group. Replacing 40% FM with BM augmented the fish immunity and antioxidant capacity, as showed by elevated the C3, C4 and IgM levels as well as CAT and SOD activities, and reduced the expression levels of NF-κB, TNF-α and Keap1 (P < 0.05). Regarding intestinal microbiota, replacing 40% FM with BM could improve the intestinal microbiota structure. The digestibility trial results showed that the apparent digestibility of protein and lipid in BM of common carp was slightly lower than FM. Conclusively, replacing 40% FM with BM could promote growth, immunity and protein metabolism of common carp, but excessive substitution level (80%) could compromise growth and hepatopancreas health.

Comparative impact of replacing fish meal with azolla on growth, water quality, and physiology of red tilapia fingerlings at varying salinities.

A 210-day experiment to assess the efficacy of substituting azolla plant powder at levels of 0, 20, 40, and 60% for fish meal on red tilapia fingerlings (RTF, initial weight of 18.23 ± 0.12 g) performance under salinity levels of 5, 18, and 28ppt. Among the various conditions, RTF-fed 20% azolla at 28 and 5ppt salinity showcased the highest specific growth rate (SGR), whereas the lowest SGR was observed in fish-fed 60% azolla at 5ppt salinity. Upon azolla incorporation, noteworthy elevations in phytoplankton, zooplankton, dissolved oxygen (DO), pH, NH3, and NO3 were noted and conversely, azolla introduction led to decreased NH4 and NO2 concentrations in all salinity levels. Further, a significant (p < 0.05) interaction between azolla levels and water salinity (S×A) significantly impacted the hematological parameters of RTF. The highest levels of superoxide dismutase (SOD), catalase (CAT), and total protein (TP) were found in RTF-fed 20% azolla at 28ppt salinity, while the lowest CAT and TP levels occurred in RTF-fed 60% azolla at 5ppt salinity. The highest aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were recorded in the RTF group fed 60% azolla at 5ppt salinity, with the lowest values seen in the group given 20% azolla at 28ppt salinity. RTF fed a 20% azolla diet at 18ppt salinity exhibited the highest lysozyme value, in contrast to the lowest value observed in the RTF group fed the control diet at 18ppt salinity. In conclusion, this study recommends the utilization of azolla at inclusion levels ranging from 20 to 40%, as it has the potential to notably enhance the immune system and elevate the survival rate of RTF.

Effects of substituting fish meal with Chlorella meal on growth performance, whole-body composition, pigmentation, and physiological health of marbled eel (Anguilla marmorata)

Chlorella meal is considered a promising alternative to fish meal in aquafeeds, but the effects of incorporating Chlorella meal as a feed ingredient on the growth and quality of eel have not been explored. The effects of partially substituting fish meal (0 %, 5 %, 10 %, 15 %, and 20 %) with Chlorella meal on the growth performance, whole-body composition, pigmentation, and physiological health of marbled eel (Anguilla marmorata) were evaluated in this study. The results revealed that dietary inclusion of Chlorella meal significantly increased the final body weight (FBW), weight gain rate (WGR), and specific growth rate (SGR), but it significantly decreased the feed conversion rate (FCR), with these parameters exhibiting linear trends (P < 0.05). The whole-body protein and fat contents were significantly higher in all groups fed with diets containing Chlorella meal compared to the control group (P < 0.05). In addition, the dorsal and abdominal skin of marbled eel exhibited an orange-yellow color, and the color intensity increased with increasing levels of dietary Chlorella meal. The color change corresponded to increased values of a* (redness), b* (yellowness), and lutein content in the fish skin (P < 0.05). The physiological health of marbled eel also improved in the groups where Chlorella meal was included. The optimal replacement rate was approximately 10 % (9 % Chlorella meal supplementation), because the whole-body protein content and most physiological health parameters were highest under this condition, and the growth performance did not show a significant increase when the fish meal replacement rate exceeded 10 % (P > 0.05). These findings indicate the potential of Chlorella meal as a promising alternative to fish meal in feed formulations, offering benefits in enhancing growth performance and quality of marbled eel.

Evaluation of earthworm meal (Eudrilus eugeniae) as fish meal replacement in juvenile Mangrove Crab (Scylla serrata) diet

Two feeding trials were conducted to evaluate the performance of the earthworm (Eudrilus eugeniae) meal (vermimeal) as a replacement for fish meal in the diet of juvenile mangrove crab (Scylla serrata) in terms of growth, feed efficiency, intermolt duration, carapace width increment, molting success, survival, and incidence of cannibalism. Four experimental diets were formulated with 0, 25, 50, and 75% fish meal protein replaced with earthworm meal protein, designated as D0, D25, D50, and D75, respectively. In the first feeding trial, the experimental diets were fed to crablets with an initial average weight of 0.09±0.007g. Each replicate comprised ten (10) crablets individually stocked in 750ml-capacity plastic containers randomly distributed in a static water bath. Final weight gain, feed efficiency and survival were measured after the 5th molt. In the second feeding trial, 150 crablets with an average weight of 0.07±0.002g were stocked at 30 crablets each in five (5) replicate tanks. Survival and incidence of cannibalism were monitored daily until the end of the culture period of 30 days. The first study showed that the growth of mangrove crab juveniles fed the diet with up to 50% of the fish meal protein replaced by the earthworm meal protein was statistically comparable to the control group. The survival of crablets in the second feeding trial was highest in D25 (33%), followed by D50 (29%), D0 (18%), and lowest in the group fed with D75 (13%). Overall, earthworm meal (Eudrilus eugeniae) can replace as much as 50% of the fish meal protein in juvenile mangrove crab (Scylla serrata) diet without negative effects on growth, carapace width increment, feed efficiency, intermolt duration, molting success, survival, and cannibalism.

The use of fishery and aquaculture by-products with Nannochloropsis sp. allows total dietary replacement of wild-caught fishmeal, fish oil and soy protein in European sea bass juveniles

Five experimental diets (CTRL, 50FMFO, 50FMFO-50MIC, 0FMFO-50MIC, 0FMFO-100MIC) were formulated to replace wild-caught fishmeal (FM), wild-caught fish oil (FO) and soy protein using fisheries, aquaculture by-products (BP) and microalgae (MIC). Fifty European sea bass juveniles were distributed in 15 tanks (initial body weight 46.66 ± 0.04 g) and reared in a recirculating aquaculture system for 88 days. Temperature, salinity, oxygen and photoperiod were kept constant throughout the experiment (22 ± 0.5 °C, 25 g L−1 and 8.0 ± 1.0 mg L−1, 12:12 light/dark, respectively). Growth, feed intake (FI), proximal composition, nutritional index, apparent digestibility, somatometric indexes, blood plasma biochemistry and digestive enzyme activity were evaluated. Also, gut microbiota composition was assessed through next-generation sequencing. Results showed that growth performance and feed digestibility were not affected by FM, FO and soy replacement using BP and MIC. Dietary replacement of 100% FM and FO with circular substitutes and 50% replacement of soymeal with microalgae increased the activity of alkaline phosphatase and chymotrypsin. Moreover, the inclusion of BP and MIC had positive effects on the gut microbiota richness and abundance. In conclusion, the utilization of BP and MIC represents a valuable alternative to FM and FO as well as soy protein in feed for European sea bass juveniles.

Clean and green bioconversion – a comprehensive review on black soldier fly (Hermetia illucens) larvae for converting organic wastes to quality products

Abstract Food security remains a pressing global concern, exacerbated by population growth, diminishing agricultural lands, and climate uncertainties. As the demand for high-quality protein sources like eggs, meat, and milk escalates, conventional feed ingredients face challenges in meeting the burgeoning needs of livestock production. The projected increase in poultry and pig consumption further strains the availability of protein-rich feed sources, necessitating sustainable alternatives. Insects, notably black soldier fly larvae (BSFL), offer numerous advantages, including efficiently converting organic substrates into high-quality protein, fat, minerals, and vitamins. Their rapid reproduction, minimal environmental footprint, and ability to thrive on various organic materials make them an attractive protein source. However, consumer acceptance remains a hurdle, hindering their direct consumption despite their nutritional value. Incorporating BSFL into animal diets, especially poultry and swine, demonstrates promising results regarding growth and production. This review comprehensively overviews BSFL production systems, processing techniques, and nutritional profiles. Various factors influencing BSFL growth and feed quality are discussed, highlighting the importance of optimizing breeding systems and feed formulations. Processing methods are elucidated to ensure the safety and quality of BSFL-based products. Nutritional analysis reveals BSFL as a rich source of essential amino acids, fatty acids, and minerals, making them suitable replacements for soybean meal and fish meal. Despite the economic and environmental benefits of BSFL utilization, challenges persist, including regulatory issues, consumer perceptions, and production scalability. Standardized production protocols and legislative frameworks are needed to facilitate the widespread adoption of BSFL in animal feed industries. In conclusion, integrating BSFL into animal diets presents a promising solution to address protein shortages in livestock production while promoting sustainable resource utilization.

Nano-selenium (nano-Se) removes the detrimental impacts of plant-based diets on the production performance and well-being of common carp (Cyprinus carpio)

Fishmeal (FM) is not a sustainable source of nutrients due to the over-exploitation of fisheries resources and increasing aquafeed costs. Plant protein (PP) sources have been utilized as FM alternatives in diets. A 60-day nutritional experiment was conducted to study the effects of the complete replacement of FM with PP ingredients in diets supplemented with nano-Se on growth performance, plasma physiological and immunological parameters, and liver antioxidant capacity of common carp (Cyprinus carpio). Five experimental diets were prepared, where FM-Control contained 35 % FM, PP-Control contained complete PP ingredients, and NSe1, NSe2, and Nse3 contained complete PP ingredients supplemented with 1, 2, and 3 mg/kg nano-Se, respectively. The growth performance of fish fed the FM-Control and NSe3 diets was higher than in the PP-Control group (P < 0.05). The best feed conversion and protein efficiency ratios were detected in the NSe3 group but were not significantly different from the FM-Control group (P > 0.05). While the highest levels of antioxidant parameters, including reduced glutathione, superoxide dismutase, catalase, and glutathione peroxidase, were detected in the liver of fish fed with the FM-Control diet, the lowest malondialdehyde concentration was measured in the NSe3 group (P < 0.05). Plasma levels of lysozyme activity, alternative complement activity, and total immunoglobulin of the FM-Control and NSe3 groups were significantly higher than in other groups (P < 0.05). The best plasma physiological parameters including the lowest levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, cholesterol, triglycerides, and low-density lipoprotein, and the highest levels of total protein, triiodothyronine (T3), and high-density lipoprotein were observed in fish fed with the FM-Control and NSe3 diets (P < 0.05). These results suggest that FM can be entirely substituted by PP in diets containing nano-Se at 3 mg/kg without harmful impacts on the performance and immunity of common carp.

Impact on Growth and Feed Availability from Including Jack Mackerel (Trachurus japonicas) Meal in Rockfish (Sebastes schlegeli) Feeds Which Otherwise Replace Fish Meal with Chicken By-Product Meal.

This study was conducted to elucidate the impact on the growth and feed availability of rockfish (Sebastes schlegeli) from including jack mackerel meal (JMM) in feeds which otherwise substitute 20% fish meal (FM) with chicken by-product meal (CBM). Six formulated feeds were designed to be isonitrogenous and isolipidic. Specifically, 55% FM was included in the control (Con) diet. In the Con diet, 20% FM was substituted by CBM, and then the graded levels (0, 20, 40, 60, and 80%) of JMM were included instead of FM, named as the C20J0, C20J20, C20J40, C20J60, and C20J80 diets, respectively. Five hundred and forty juvenile rockfish (initial weight of 11.2 g) were assigned to 18 tanks. All experimental feeds were fed to triplicate groups of rockfish twice daily for 8 weeks. Superior weight gain, specific growth rate (SGR), and feed intake of rockfish fed the C20J60 and C20J80 diets compared to rockfish fed the Con and C20J0 diets were observed. However, the feed utilization, biological indices, proximate composition, amino acid profiles, and blood chemistry of the rockfish were not affected by the dietary treatments. The slightly but not significantly higher economic profit index and growth performance were obtained in the C20J60 diet compared to the C20J80 diet. In conclusion, the C20J60 diet was the most recommendable treatment based on the improvement in growth performance (weight gain and SGR) and feed intake of rockfish, and the highest economic return to farmers.

Replacement of fishmeal by fermented spent coffee ground: Effects on growth performance, feed stability, blood biochemistry, liver, and intestinal morphology of African catfish (Clarias gariepinus)

There has been a consistent interest in the aquaculture industry in the use of plant elements as a substitute for fish meal (FM). The present study aimed to examine the impact of substituting FM with varying proportions of fermented spent coffee grounds (FCG) on the growth performance, feed stability, blood biochemistry, liver, and intestinal histology of African catfish, Clarias gariepinus. Five isonitrogenous diets were formulated with a crude protein content of 32 %. These diets were created with different percentages of FM replacement, specifically 0 % (T1), 10 % (T2), 20 % (T3), 40 % (T4), and 80 % (T5). The fish were then fed these diets for a duration of 70 days. The results showed that fish provided with 10 % FCG (T2) gave the highest improvement (p < 0.05) in growth conditions compared with other treatments. The feed’s physical properties were varying, but floatability and water stability were highest in T2 diets. Total bacteria (TB) in feed and intestine were more elevated in fish fed with 10 % FCG compared to other treatments. The histopathological damage in the intestine and liver morphology was observed when the level of inclusion of FCG was increased in all treatments. In addition, T2 gave the highest value (p < 0.05) in villus length, width, and crypt depth. Some parameters were improved in both blood haematology and blood biochemical parameters, and T2 gave the highest value (p < 0.05) in white blood cells, lymphocytosis, monocytes, red blood cells, haemoglobin, albumin, globulin, total protein, and creatine. In summary, the substitution of 10 % FCG with FM holds potential for application within the aquafeed sector, as it has been observed to contribute to enhanced growth and improved health conditions in African catfish and other freshwater species.

A Sustainable Diet for Tambaqui Farming in the Amazon: Growth Performance, Hematological Parameters, Whole-Body Composition and Fillet Color.

The aim of this study was to produce feed based on locally sourced ingredients for tambaqui farming in Amazon. Diets were formulated with increasing levels (0, 25, 50, 75 and 100%) of defatted black soldier fly larvae meal (BSFL) as a replacement for fish meal (FM), and cassava by-products in the same proportion (tuber residues, peel and leaves). A conventional diet (CO) was used as the control. Juvenile tambaqui (24.61 ± 1.14 g) were housed in 24 tanks in a recirculation aquaculture system. Neither diet rejection nor mortality were observed. Fish fed cassava by-products showed similar feed conversion rates (FCR 1.76); however, these values were worse than those observed in fish fed the CO (FCR 1.33). No differences were observed in the whole-body composition of the fish. The fillets of fish fed cassava by-products had a yellow color due the carotenoids present in the leaves. Dietary BSFL and cassava by-products can contribute to the sustainability of Amazonian aquaculture. Further studies with a lower proportion of cassava leaves in the diet formulation are recommended so as to ensure enhanced diet digestibility and less impact on the color of the fillets.