Search Results (194)

The use of eco-organic ingredients as a source of protein in aquaculture diets needs important attention due to the growing demand for organic seafood products. The present study evaluated the effects of fish meal substitution by different organic ingredients on the growth, body composition, retention efficiency, enzyme activity, and nutrient digestibility of white shrimp Penaeus vannamei. The four dietary formulations tested were formulated with organic ingredients and the fish meal was replaced by the following organic protein meals: Iberian pig viscera meal (PIG), trout by-product meal (TRO), insect meal (FLY), and organic vegetable meal (WHT), in addition to a control diet (CON) that included 15% fish meal. A growth trial was carried out for 83 days, raising 1 g shrimp to commercial size (20 g). Shrimp were stocked at 167 shrimp/m³ (15 individuals per 90 L tank). The results showed that the growth obtained by shrimp fed with TRO (19.27 g) and PIG (19.35 g) were similar in weight gain to the control diet (20.76 g), while FLY (16.04 g) and WHT (16.73 g) meals resulted in a significant lower final weight. The FLY diet showed significantly lower protein digestibility (68.89%) compared to the CON, PIG, TRO, and WHT diets, and significantly higher trypsin activity (0.17 mU/g) compared to shrimp fed with the PIG, TRO, and WHT diets. Shrimp fed with WHT have a significantly lower body weight percentage of protein (19.69%) than shrimp fed with the WHT and TRO diets, and some significant differences in dietary aminoacidic levels affecting amino acid body composition. These results indicate that Iberian pig viscera and trout by-product meal can successfully replace fish meal in Pacific white shrimp aquaculture. Full article

Restaurants and open markets generate considerable quantities of organic waste. Converting these residues into poultry feed ingredients offers a sustainable disposal route. This study aimed to evaluate the nutritional and sensory viability of a novel feed complement formulated from Bonito fish meal (Sarda chiliensis chiliensis) and Única potato peel flour (Solanum tuberosum L. cv. Única). This study was conducted in three phases: (i) production and nutritional characterization of the two by-product flours; (ii) formulation of a 48:52 (w/w) blend, incorporated into broiler diets at 15%, 30%, and 45% replacement levels over a 7-week trial divided into starter (3 weeks), grower (3 weeks), and finisher (1 week) phases; and (iii) assessment of growth performance (weight gain, final weight, and feed conversion ratio), followed by a sensory evaluation of the resulting meat using a Check-All-That-Apply (CATA) analysis. The Bonito fish meal exhibited 50.78% protein, while the Única potato peel flour was rich in carbohydrates (74.08%). The final body weights of broiler chickens ranged from 1872.1 to 1886.4 g across treatments, and the average feed conversion ratio across all groups was 0.65. Replacing up to 45% of commercial feed with the formulated complement did not significantly affect growth performance (p > 0.05). Sensory analysis revealed that meat from chickens receiving 15% and 45% substitution levels was preferred in terms of aroma and taste, whereas the control group was rated higher in appearance. These findings suggest that the formulated feed complement may represent a viable poultry-feed alternative with potential sensory and economic benefits, supporting future circular-economy strategies. Full article

Background: Aquaculture increasingly seeks sustainable alternatives to fishmeal, a key protein source in fish diets. Black Soldier Fly Larvae (BSFL) meal is a promising substitute, but its effects on fish growth, immunity, and gut health need further investigation. This study aimed to evaluate the impact of varying BSFL inclusion levels on juvenile hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂), a widely farmed species in tropical aquaculture. Methods: Juvenile hybrid grouper were fed diets with four levels of BSFL substitution (0%, 10%, 30%, and 50%) over 56 days. Key metrics such as growth performance, immune function, antioxidant capacity, and gut transcriptome were analyzed. Results: Replacing fish meal with BSFL meal had no significant effect on the survival rate of hybrid grouper (p > 0.05) but significantly affected growth performance, immune function, and antioxidant capacity (p < 0.05). BSFL10 and BSFL30 groups showed good growth and elevated immune enzyme activity, with significantly higher HIS levels (p < 0.05); the Wf of the BSFL10 group was comparable to the control. However, excessive replacement (BSFL50) led to reduced growth (Wf significantly lower, p < 0.05) and increased oxidative stress, as indicated by higher CAT activity (p < 0.05). Transcriptomic analysis revealed upregulation of immune- and metabolism-related genes with increasing BSFL levels, with immune pathways notably activated in the BSFL50 group. Conclusions: BSFL meal is a promising alternative to fishmeal in juvenile hybrid grouper diets, with moderate inclusion (10–30%) being most beneficial. Excessive BSFL substitution (50%) may impair fish health, highlighting the need for careful formulation in aquaculture diets. Full article

A two-factorial experiment was conducted to evaluate the potential for improving the palatability and utilization of tuna by-product meal (TBM) as a replacement for fish meal (FM) via supplementing the diet of juvenile greater amberjack (Seriola dumerili) with powdered salmon roe liquid (PSRL). FM protein in the control diet (C) was partially replaced with TBM at levels of 25% (T25R0) and 40% (T40R0). PSRL was then added at 5% and 10% to both the T25R0 and T40R0 diets, resulting in the formulations T25R5, T25R10, T40R5, and T40R10. After a 6-week rearing period, during which groups of 30 juveniles (mean initial weight of approximately 1.7 g) were stocked in 500 L tanks, there were no significant differences in the final mean weight, weight gain, or specific growth rate among fish fed diets C, T25R0, and T25R5. However, the other experimental diets showed significantly lower values compared to the C diet (p < 0.05). PSRL supplementation did not significantly enhance either palatability or feeding rate in TBM-based diets (p > 0.05). Two-way ANOVA indicated that only FM replacement with TBM had a significant effect on the growth parameters mentioned above (p < 0.05). A significantly lower whole-body crude lipid content was observed in all test diets compared to that in the C diet, resulting in significantly lower lipid retention efficiency in all test groups except T25R5 and T25R10 (p < 0.05). These results suggest that 25% of FM protein can be replaced with TBM protein in the diet of juvenile greater amberjack, but PSRL does not effectively address the palatability issues associated with TBM-based diets. Full article

This study explored the potential of insect proteins as an alternative to traditional meat and bone meals in nutritionally balanced dry expanded dog food. Four formulations containing black soldier fly larvae meal (BSFL), cricket flour (CF), poultry meal (PM), or fish meal (FM) at 30% inclusion were evaluated using powder rheology, extrusion trials, and analyses of kibble expansion and texture. BSFL and FM had lower specific basic flow energy (<13 mJ/kg) compared to PM and CF (>14 mJ/kg), leading to better flowability and improved extrusion stability and product consistency. High fat and chitin contents in CF and BSFL, respectively, resulted in higher bulk densities (328–382 g/L) than meat-and-bone-meal-based products (304–306 g/L). The insect-meal-based kibbles also had either a fragile (peak crushing force < 7 kg for BSFL) or very hard texture (force > 13 kg for CF). Results from a second experiment showed that including BSFL meal at lower levels (10%) alongside poultry meal mitigated the negative effects on kibble quality while improving process stability. Overall, the study suggests that defatting and partial, rather than complete, replacement of traditional proteins with insect meal could be more viable strategies for producing consistent, high-quality extruded pet food. Full article

Aquaculture advancement depends on alternative raw materials to reduce reliance on fishmeal (FM) and fish oil (FO) from extractive fisheries. Strategies like restricted feeding reduce costs and improve sustainability by minimizing feed waste and enhancing water quality, while selective breeding boosts growth and adapts fish to innovative diets. However, these measures may affect quality and shelf life. Gilthead seabream selected for high growth or non-selected were fed in 500 L tanks for 300 days until apparent satiety (AS) or with food restrictions (85AS or 65AS) using a control diet with low FM and FO balanced with vegetable ingredients, and an alternative diet (ALT) where FM was substantially replaced with insect, poultry by-product, feather, and porcine blood meals, while FO was completely replaced by microalgae, poultry, and salmon by-product oils. The ALT diet improved EPA + DHA levels, n-3/n-6 ratio, and fillet hardness. The selected fish outperformed the non-selected ones in growth and were more resilient to ALT diet and feeding restrictions. The 85AS feeding strategy optimized fillet quality by preventing lipid accumulation and muscle adaptations, as observed with the other feeding strategies. Combining sustainable feed formulations, genetic selection, and moderate feed restriction enables a viable, long-term strategy for high-quality, environmentally responsible seabream farming. Full article

Macroalgae biomass produced in integrated biofloc systems can become a high-quality nutritional product to replace ingredients in the diet of tilapia. This study aimed to evaluate the effects of different concentrations of Ulva lactuca on the performance and antioxidant capacity of Nile tilapia. There were four isoprotein and isolipid diets with 5%, 10%, and 15% macroalgae meal, and a control treatment without macroalgae inclusion. The experiment lasted for 42 days in a recirculating system, with animal performance, blood sampling, and proximal composition being carried out. To assess the potential benefits of including algal biomass, a salinity stress test was carried out on the fish, and samples were collected for biochemical analysis. There were no significant differences in carcass performance and composition between the treatments. The results showed that the inclusion of 10% macroalgae resulted in a higher granulocyte count, while the antioxidant capacity obtained better results in the 5 and 10% macroalgae inclusions, followed by the modulation of the antioxidant system, as evidenced by an increase in glutathione-S-transferase activity and reduced glutathione levels. However, protein and lipid oxidation did not occur only in the 5% macroalgae inclusion compared with the treatments with higher algae inclusion. Therefore, the inclusion of 5% macroalgae in the tilapia diet is indicated to improve antioxidant capacity in the face of stress. Full article

A combination of meat meal (MM) and chicken byproduct meal (CBM) were evaluated as fish meal (FM) replacers in the diets of juvenile red seabream (Pagrus major). The control diet was formulated with 60% FM (CON). Four other diets were designed by reducing the FM levels to 45, 30, 15, and 0% by adding 14, 28, 42, and 56% MM and CBM in a 1:1 ratio to compensate for the reduced protein level (designated as MC14, MC28, MC42, and MC56, respectively). Red seabream (averaging 4.57 g) were distributed among 15 fiberglass tanks (40 fish/tank) and assigned to one of three replicates of the diet. After an eight-week long feeding trial, the growth performance of the fish fed the CON, MC14, and MC28 diets were comparable with the control group, and were significantly higher than the MC42 and MC56 groups. Feed utilization was significantly higher in the MC28 group compared to the other groups. The lowest growth and feed utilization were observed in the MC56 group. Serum lysozyme and SOD activities were significantly reduced when the dietary FM level decreased. Plasma total cholesterol levels were significantly reduced when the FM level was decreased in the diets, exhibiting a significant linear trend. The CON group exhibited a significantly higher cholesterol level compared to the MC42 and MC56 groups. The muscle amino acid profile was not significantly affected. The muscle myristic acid (14:0) was significantly decreased, while the palmitic acid (16:0) level increased with the increase of MM and CBM in the diets. Therefore, the results indicate that the combination of MM and CBM can be used to replace 50% of the FM from the red seabream diets without negative influences compared to a diet containing 60% FM. Full article

This study was conducted to investigate the effects of replacing fish meal with either whole-fat or defatted krill powder on the growth, body color, immunity, and related gene expression of red–white koi carp. A total of 630 red–white koi carp with an initial body mass of 13.5 ± 0.05 g were randomly divided into seven groups with three replicates per group and 30 fish per replicate. The control group was fed a basic diet (C0). The other six diets were supplemented with different levels of whole krill meal or defatted krill meal as replacements (10% whole fat, 20% whole fat, 30% whole fat, 10% defatted, 20% defatted, and 30% defatted) in the experimental groups, named W10, W20, W30, D10, D20, and D30, respectively, for a total duration of 60 days. The growth, body color, immunity and gene expression indexes were measured in the koi after completion. The results indicate the following. (1) Compared with C0, the experimental groups of koi showed a significant increase in the specific growth rate (SGR) (p < 0.05), while the hepatosomatic index (HSI) and viscerosomatic ratio (VSI) decreased. Additionally, there was a significant increase in the relative expression level of insulin-like growth factor (IGF-1) in both the liver and muscle (p < 0.05). (2) The experimental groups of koi carp exhibited a significant increase in the carotenoid content in the scales and skin, as well as an elevated relative expression level of the tyrosinase (TYR) gene in the muscle (p < 0.05). (3) The lysozyme (LZM) and superoxide dismutase (SOD) activities were significantly increased in the experimental groups compared to C0 (p < 0.05). Additionally, the SOD activity was significantly higher in the defatted groups than in the whole-fat groups (p < 0.05). Furthermore, the liver alkaline phosphatase (AKP) activity was significantly lower in the D20 and D30 groups compared to the other five groups. (4) The expression level of LPL was significantly lower in the liver and muscle of the whole-fat group compared to the defatted group (p < 0.05). Tissue section observation revealed that the hepatocytes in the W20 and W30 groups exhibited a reduced size and an increased lipid droplet count, while the vacuolar degeneration of the hepatocytes increased in the D30 group. In conclusion, replacing fish meal with whole-fat or defatted krill powder or defatted Antarctic krill meal significantly improves the growth performance, body color, and immunity of red–white koi carp. However, excessive addition of krill meal can easily cause liver damage. The recommended replacement level for whole krill powder is 20% to 30%, while defatted krill powder should be replaced at a level of 10% to 20%. Full article

Replacing fishmeal (FM) with plant-based protein sources remains a significant challenge, particularly for carnivorous fish. This study investigates the effect of dietary Lentinus edodes fermentation (LEF) supplementation on Japanese eel (Anguilla japonica) fed with fermented soybean meal (FSM) as a partial FM replacement. The positive control consisted of 64% FM (Con), and the negative control (FSM group) included 52% FM plus 12% FSM. Two experimental diets were formulated by adding 2% LEF (LEF2 group) and 3% LEF (LEF3 group) to the negative control diet. The experimental diet was administered to Japanese eels weighing 62.50 ± 2.14 g for 12 weeks. The experimental fish were randomly assigned to four groups, with three replicates of 100 fish per group. The results indicated that growth performance and feed efficiency were significantly reduced in the FSM group, but were significantly improved by LEF supplementation (p < 0.05). LEF supplementation did not significantly affect muscle crude fat and protein content compared to the FSM group (p > 0.05), but significantly increased muscle amino acid content and levels of certain fatty acids (linoleic acid, γ-linolenic acid, eicosatrienoic acid, DHA) (p < 0.05). LEF supplementation reduced serum TC and LDL-C levels, increased HDL-C levels, significantly increased CAT and T-SOD activities, and reduced MDA levels in both serum and liver (p < 0.05). ALT and AST activities were significantly elevated in the FSM group, accompanied by liver histological abnormalities, which were improved by LEF supplementation. LEF supplementation increased the thickness of the muscularis, villus height, and goblet cell count in the intestine (p < 0.05). Compared to the control, the FSM group significantly upregulated spleen tnf-α gene expression and downregulated the expression of anti-inflammatory factors (ifn-α, ifn-γ, socs1, mavs). LEF supplementation ameliorated the reduced immunocompetence induced by FM replacement with FSM by enhancing the expression of immune-related genes (irak4, ifn-α, ifn-γ, irf3, irf11, socs1, mavs, traf3) in the spleen. These results suggest that the beneficial effects of LEF supplementation on growth performance and feed efficiency may be attributed to its improvement of liver damage and intestinal histology, as well as its enhancement of antioxidant capacity and immunity. Full article

Soy protein concentrate (SPC) is a cost-effective alternative to fish meal (FM) in aquaculture, but its deficiency in essential amino acids, particularly methionine, limits its application. This study evaluated the effects of methionine supplementation on growth, liver and intestinal health, and muscle quality in hybrid sturgeon (Acipenser baerii ♀ × A. schrenckii ♂) fed SPC-based diets. Four diets were formulated: an FM control diet, and SPC diets supplemented with 0% (M0), 0.25% (M2.5), and 0.50% (M5) methionine. Replacing FM with SPC without methionine (M0) significantly reduced weight gain and the protein efficiency ratio (PER) while increasing the feed conversion ratio (FCR) and hepatic lipid accumulation. Methionine supplementation (M5) restored growth performance, the PER, and muscle texture to levels comparable to the FM group. Intestinal enzyme activities (lipase and trypsin), villus height, and goblet cell counts significantly improved in the M5 group. Gene expression analysis showed that M5 upregulated tight junction genes (claudin1, occludin) and anti-inflammatory genes (tgfβ, lysozyme) while reducing pro-inflammatory cytokines (il1β, il8). In the liver, M5 reduced oxidative stress markers such as malondialdehyde (MDA) and improved antioxidant enzyme activities (SOD, CAT) while optimizing lipid metabolism, as evidenced by lower triglyceride (TG) and total cholesterol (TC) levels. Muscle quality analysis showed that M5 significantly increased muscle hardness, chewiness, and fiber density compared to M0. In conclusion, methionine supplementation at 0.50% effectively mitigates the negative effects of SPC, improving growth, liver and intestinal health, and muscle quality in hybrid sturgeon. Full article

Serum proteins are essential for maintaining osmotic pressure, regulating pH, transporting metabolites, and supporting immune responses. Studying the effects of plant-based diets on these proteins is crucial to understanding their impact on fish health and immune function. Methods: This study was conducted in a recirculation system, with rainbow trout distributed across nine tanks and fed three diets: fishmeal (control), medium plant meal (MPM; 40% of fishmeal replacement), and high plant meal (HPM; 80% of fishmeal replacement). Plasma protein and plasma glucose levels were measured at the initial and final stages, under both fasting (24 h after fast) and postprandial (6 h after fed) conditions, to assess dietary impacts. Additionally, the hepatosomatic index (HSI) was calculated at the end of the experiment to evaluate potential liver adaptations to the diets. Results: The initial protein and glucose levels were similar across all groups. However, by the end of the treatment, the fishmeal-fed group showed significantly higher total protein and globulin levels, while the albumin levels remained consistent across diet types. A significant interaction between sampling time and dietary treatment in fish reduced the clarity of dietary effects on postprandial plasma glucose levels. Furthermore, the HSI was significantly lower in fish fed the high plant meal (HPM) diet compared to the fishmeal and medium plant meal (MPM) groups, suggesting potential metabolic adaptation in response to plant-based diets. Conclusions: Replacing fishmeal with plant-based proteins in rainbow trout diets reduces total globulin and protein concentrations but leaves albumin unaffected, alongside reductions in fasting and postprandial glucose levels. The low growth and different HSI in fish fed plant-based diets highlights potential liver stress, emphasizing the need for further research to optimize sustainable aquaculture feeds while maintaining fish health and performance. Full article

Aquaculture, one of the world’s most rapidly growing food sectors, faces several concerns about its sustainability. A major concern is using fishmeal and fish oil from ocean-derived small pelagic fish (sardine, anchovy, etc.) in aquaculture feed. The aquafeed industry is seeking new sustainable ingredients to replace fish meal. This study focused on microalgal co-product, Nannochloropsis sp. QH25 co-product (leftover after oil extraction for nutraceuticals) is a novel aquafeed ingredient that can replace fishmeal in rainbow trout diets. A nutritional feeding experiment was conducted and compared fishmeal-containing rainbow trout diets with microalgal co-products that replaced fishmeal as follows: 0% replacement in reference diet (fishmeal, no microalgal co-product) and test diets with 33%, 66%, and 100% replacement of fishmeal using microalgal-product. Results showed the complete replacement diet yielded fish growth, feed conversion, and survival similar to the reference diet. Depositions of macronutrients, amino acids, fatty acids, macro minerals, and several trace elements in the filet were not significantly different across diets. Economic conversion ratio (ECR) analysis showed that the rainbow trout fed the 100% replacement diet had the lowest feed cost per kg of fish produced. Microalgal co-products can fully replace fishmeal in trout feed while maintaining fish performance, flesh composition, and cost-effectiveness. Full article

Fish meal (FM) replacement is essential for sustainable aquaculture development. This study investigated the effects of FM replacement with poultry by-product meal (PBM) on growth performance, hepatic and intestinal health and ammonia nitrogen stress resistance in mandarin fish (Siniperca chuatsi). A 52-day feeding trial was conducted using PBM to replace fish meal at levels of 0%, 17.5%, 35.0%, 52.5% and 70.0%. The results showed that FM replacement with PBM did not influence growth performance in mandarin fish. Moderate PBM replacement (≤35.0%) did not harm liver health and enhanced the intestinal structure. However, excessive replacement (≥52.5%) caused hepatocyte damage, reduced antioxidant capacity and decreased survival under ammonia nitrogen stress. Notably, 70% PBM replacement led to severe hepatic lipid accumulation, inhibiting fatty acid β-oxidation and triglyceride hydrolysis pathways. Furthermore, high PBM levels (≥52.5%) also reduced intestinal muscularis thickness, downregulated tight junction proteins and induced inflammation. In conclusion, while PBM replacement does not hinder growth, maintaining levels below 35.0% (PBM ≤ 28.5%) is essential for preserving hepatic lipid metabolism, intestinal health and antioxidant defense in mandarin fish. Full article

The current experiment is conducted to determine the effects of chicken by-product meal (CBM) as a fish meal (FM) replacer in diets, with or without the inclusion of jack mackerel (Trachurus japonicus) meal (JMM), on the growth and feed availability of rockfish (Sebastes schlegeli). A two-way ANOVA experimental design [FM replacement level (FMRL, 25% and 50%) × JMM inclusion (without and with)] was adopted. The control (Con) diet contained 55% FM. In the Con diet, 25% and 50% of FM were substituted with CBM, either without or with the inclusion of 22% JMM, referred to as the CBM25, CBM50, CBM25J, and CBM50J diets, respectively. A total of 375 juvenile fish were distributed into 15 tanks with triplicates. The 25% FM replacement diets led to significantly (p < 0.003 and p < 0.004, respectively) greater weight gain and specific growth rate (SGR) of rockfish than the 50% FM replacement diets. Furthermore, the CBM-replaced diets with JMM inclusion led to significantly (p < 0.003 and p < 0.002, respectively) greater weight gain and SGR of fish compared with those without JMM inclusion. Weight gain and SGR of rockfish fed the Con and CBM25J diets were significantly (p < 0.001 for both) greater than those of fish fed the CBM25, CBM50, and CBM50J diets. However, neither dietary FMRL nor JMM inclusion had significant (p > 0.05) effects on feed consumption, blood chemistry, or the biochemical composition of rockfish. In conclusion, 25% of FM could be replaced with CBM in the 55% FM-based diet, including JMM, without adverse effects on the growth, feed availability, blood chemistry, or biochemical composition (proximate composition and amino and fatty acid profiles) of rockfish. Full article