Dietary Fish Research Articles

Growth performance, antioxidant, and immune responses of Nile tilapia (Oreochromis niloticus) fed on low-fishmeal diets enriched with sodium chloride and its adaptability to different salinity levels

The current investigation assessed the beneficial impacts of dietary sodium chloride (NaCl) on the growth performance, oxidant/antioxidant, and immune responses of Nile tilapia (Oreochromis niloticus) and its adaptability to different salinity levels. After acclimating the fish to the laboratory conditions for 2 weeks, the acclimated fish (10.5 ± 0.16 g) were randomly distributed into 25 110-L rectangular glass tanks (15 fish/tank) to represent five groups in five replicates. The fish were fed with experimental feeds fortified with 0.0 (control), 5, 10, 15, and 20 g NaCl/kg feed for 60 days. Following the nutritional experiment, fish of all groups were adapted to different salinity levels from 0 to 32 g /L for a further 3 weeks, during which fish mortality was recorded. Blood samples were taken after the feeding trial and at a salinity level of 24 g/L. Growth performance and hematological parameters (WBCs, RBCs, hemoglobin, and hematocrit), total protein, albumin, globulin, digestive enzymes, antioxidant activity, and immunity status were markedly improved with increased NaCl rates in the fish diets up to 10 g/kg feed, after which all previous parameters were declined. On the other hand, feeding fish on a diet containing 10 g NaCl/kg feed showed substantially lower levels of cortisol, glucose, cholesterol, triglycerides, aspartate transaminase (AST), alanine transaminase (ALT), and malondialdehyde (MDA). Exposing the control fish group to salinity stress (32 g/L) for 3 weeks markedly decreased their digestive enzyme activity, immunity status, and antioxidant response, along with significant increases in cortisol, glucose, cholesterol, triglycerides, AST, ALT, and MDA levels. Conversely, feeding fish on a diet containing 10 g NaCl/kg feed alleviated the negative impacts of salinity stress and helped fish to tolerate salinity stress up to 24 g/L.

Gelatins derived from aronia-supplemented fish diets: Structural effect and molecular simulation.

Fish gelatin, a sustainable substitute for mammalian gelatin, frequently exhibits weaker gel strength and thermal stability, limiting its industrial uses. This study investigated an in vivo method to improve functional characteristics by supplementing Nile tilapia diets with Aronia extract. The control diet (A0) contained no Aronia extract, while the remaining four diets consisted of commercial pelleted feed enriched with 250mg/kg (A250), 500mg/kg (A500), 750mg/kg (A750), and 1000mg/kg (A1000) of Aronia extract. The gelatin samples revealed thermo-reversible behavior with increasing temperature. A250 exhibited the highest melting temperature of 29.65°C, compared to 27.43°C for A0. The gelation temperature for A250 was 17.56°C, indicating a relatively stable gelatin structure. The elastic modulus (G') was the highest in A250, suggesting an improved gel network compared to the other samples. The gelation rate constant (kgel) was highest in A250 (540.67Pa), followed by A750 (447.32Pa), A500 (393.85Pa), and A1000 (370.97Pa), compared to 391.15Pa for A0. The gel strength was improved, with A250 showing the highest value at 133.9g, followed by A750, A1000, and A500, while A0 was 102.1g. The glass transition temperatures (Tg) for A250, fish gelatin (FG), bovine gelatin (BG), and A0 were 76.72°C, 74.31°C, 70.71°C, and 73.52°C, respectively. Molecular docking studies revealed strong binding interactions between A250 and phenolic compounds, which contributed to the observed structural enhancements. These findings suggest that supplementing fish diets with Aronia extract can substantially enhance gelatin quality, offering a promising alternative to traditional gelatin sources.

Application of two crucial hemicellulolytic enzymes in fish diet: Xylanase and mannanase

Application of two crucial hemicellulolytic enzymes in fish diet: Xylanase and mannanase

Effects of yellow passion fruit (Passiflora edulis) residue in diets for Oreochromis niloticus in a recirculating aquaculture system with integrated lettuce cultivation

The inclusion of agro-industrial residues in fish diets represents a sustainable strategy for modern aquaculture. This study investigated the effects of incorporating yellow passion fruit (Passiflora edulis) residue into diets for Nile tilapia (Oreochromis niloticus) fingerlings reared in a recirculating aquaculture system (RAS) integrated with lettuce (Lactuca sativa) cultivation. Over a 60-day period, 12 tanks were used in a completely randomized design with four treatments: T1 (12% yellow passion fruit residue (PFR) with lettuce), T2 (12% PFR without lettuce), T3 (0% PFR with lettuce), and T4 (0% PFR without lettuce), each with three replicates and a stocking density of 25 fish per tank (3.75 ± 0.40 g; 5.84 ± 0.50 cm). The presence of lettuce significantly reduced ammonia levels, improving water quality. No significant differences in growth performance were observed among treatments. Antioxidant capacity was enhanced by the inclusion of 12% PFR, showing higher activities of catalase, superoxide dismutase and glutathione S-transferase. Despite a reduction in intestinal villi height in fish fed 12% PFR, no negative impacts on growth performance were identified. The study demonstrates that integrating lettuce into the RAS is effective for water treatment and that using up to 12% PFR in diets is a sustainable, functional, and promising approach for Nile tilapia, contributing to more efficient and environmentally responsible production systems.

Physiological and growth responses of tambaqui (Colossoma macropomum) fed Croton conduplicatus essential oil and challenged with Aeromonas hydrophila.

This study aimed to assess the effect of Croton conduplicatus essential oil (CCEO) in diets for tambaqui (Colossoma macropomum) (14.50 ± 0.07g), a native Amazonian fish. Five diets (29.25% digestible protein; 3063.14kcal digestible energy) were prepared: 0.00 (control), 0.25, 0.50, 1.00, and 1.50 mL CCEO kg diet-1 and evaluated for 60 days, followed by 14 additional days of bacterial infection with Aeromonas hydrophila. Fish were fed until apparent satiation four times daily and maintained in 1,000-L tanks (n = 15 fish per tank; 5 tanks per treatment; randomized design) in a recirculatory aquaculture system. The main chemical compounds of CCEO were the monoterpenes 1,8-Cineole (20.72%), p-Cymene (12.45%), and α-Phellandrene (11.46%). Animals had no mortality, even after the bacterial infection, and CCEO did not influence the number of lesions in infected fish. According to quadratic regression analysis, feeding fish diets containing 0.85 mL CCEO kg-1 increased their growth parameters and feed intake. The feed conversion ratio was reduced with 0.25 mL CCEO kg diet-1. Before infection, the regression showed that the 1.00 mL CCEO kg diet-1 reduced erythrocytes and increased hemoglobin, hematimetric indices, plasma glucose, total cholesterol, albumin levels, and plasma and liver alanine aminotransferase (ALT) activities. After bacterial infection, quadratic regression analysis showed that the control group had the highest plasma glucose and albumin values, and the treatment 0.50 mL CCEO kg diet-1 increased mean corpuscular volume values and decreased plasma ALT activity. In conclusion, 0.85 mL CCEO kg diet-1 is recommended for tambaqui because it can potentially improve growth performance and hemato-biochemical responses; however, CCEO did not influence responses against aeromoniasis.

Nutritional composition and processing methods of black soldier fly larvae for fish feeding

<p>This review explores the potential of black soldier fly (BSF) larvae as a sustainable alternative to fishmeal and soybean meal in aquaculture. BSF larvae offer a valuable protein, fat, and chitin source while contributing to waste reduction and nutrient recycling. Feed industries can effectively incorporate BSF larvae into fish diets without negatively impacting growth performance or health. However, the optimal inclusion levels and potential challenges associated with BSF-based diets vary among fish species. Future research should focus on further optimizing BSF production and processing methods and investigating the long-term effects of BSF-based diets on fish health and reproductive performance. BSF larvae can significantly promote sustainable and efficient aquaculture practices by addressing these areas.</p>

A preliminary study on the effect of the combination of Blaptica dubia (Order: Blattodea) and commercial fish feed on red hybrid tilapia, Oreochromis sp.

Fish meal and soybean meal are the main sources of protein in most fish feeds. Changes in feed and fish production costs are a concern for aquaculturists. Because they are a natural component of fish diets and have a high protein, vitamin, and digestibility profile, insects may be able to contribute to meeting the growing demand for fishmeal. This study was a preliminary investigation on the effect of various dietary combinations (Blaptica dubia + commercial pellet) on the weight of red hybrid tilapia, Oreochromis sp. fry. The Oreochromis sp. fingerlings were acclimatized to the laboratory condition for seven days. Five different mixtures of feed were concocted [T1 (60% B. dubia + 40% commercial pellet), T2 (70% B. dubia + 30% commercial pellet), T3 (80% B. dubia + 20% commercial pellet), T4 (90% B. dubia + 10% commercial pellet) and T5 (100% B. dubia)]. The control group of Oreochromis sp. was fed with 100% commercial pellet. Throughout the experiment period, the growth of the fish was monitored weekly for 15 weeks. Then, the fish were euthanatized, and the liver was subjected to histology analysis. The results show that T3, T4, and T5 feed mixtures promote the best growth and survival rate for Oreochromis sp. while causing liver damage. T1 and T2 fish feed ratios are better alternatives as they promote healthy fish and increased weight (p < 0.05).

The study of high-protein plant components on the example of soybeans and corn for aquaculture feed

It is important to use nutritious compound feeds with high content of protein in order to obtain qualitative marketable fish products under an intensive cultivation. During the production of high-protein aquaculture feeds, protein-rich animal and plant ingredients should be added to the composition. To such components refer: fish flour, meat-and-bone meal, wheat, corn, various types of soybeans, etc. Animal ingredients can be partially replaced by vegetable ingredients, but should not be 100%. Popular plant-based feed additives are soybean and corn. They are rich sources of plant protein which make them an ideal supplement to form a complete fish diet, especially in conditions of the intensive cultivation. These ingredients are often cheaper in comparison to animal proteins, which is the reason why the use of these ingredients makes feed more affordable for fish producers. For producers, semi-finished products of two or more ingredients are produced now as pellets or dry mixes. It is made to simplify the production process. In the majority of cases, these additives include a combination of animal protein and plant protein. This paper considers plant components such as soybean and corn in combination with fish flour for the manufacture of compound feeds. It also presents amino acid compositions of these components. Studies on the determination of the amount of proteins, fats and carbohydrates in experimental feeds containing soybean and corn are conducted and described. In the course of the experiment it is revealed that the feed with soybean content has a higher percentage of crude protein content, but the feed with corn has a higher content of carbohydrates in its composition.

Evolution of fast-growing piscivorous herring in the young Baltic Sea

AbstractThe circumstances under which species diversify to genetically distinct lineages is a fundamental question in biology. Atlantic herring (Clupea harengus) is an extremely abundant zooplanktivorous species that is subdivided into multiple ecotypes that differ regarding spawning time and genetic adaption to local environmental conditions such as temperature, salinity, and light conditions. Here we show using whole genome analysis that multiple populations of piscivorous (fish-eating) herring have evolved sympatrically after the colonization of the brackish Baltic Sea within the last 8000 years postglaciation. The piscivorous ecotype grows faster, and is much larger and less abundant than the zooplanktivorous Baltic herring. Lesions of the gill rakers in the piscivorous ecotype indicated incomplete adaptation to a fish diet. This niche expansion of herring in the young Baltic Sea, with its paucity of piscivorous species, suggests that empty niche space is more important than geographic isolation for the evolution of biodiversity.

Probiotics on Commercial Fish Growth: A Meta-Analysis

Probiotics are widely used in fish diets to improve health and growth, but a detailed analysis of their impact on fish growth performance has been lacking. This study conducted a meta-analysis of 86 relevant articles out of 627 identified, focusing on specific growth rate (SGR) and feed conversion ratio (FCR). The study examined the effects of different variables, including the number of probiotic strains used, the type of water (freshwater, saltwater, or brackish), and the concentration of probiotics. The results indicated that probiotics had a significant positive effect on both SGR and FCR in fish. There was no notable difference in growth performance between diets with single strains versus multiple strains of probiotics. However, freshwater fish showed a better response to probiotics compared to saltwater and brackish water fish. The analysis found that the minimum effective concentration of probiotics for improving SGR was 7 log CFU/g, while 8 log CFU/g was needed to enhance FCR. Overall, this meta-analysis offers valuable insights into optimizing the use of probiotics in aquaculture, demonstrating that specific factors such as water type and probiotic concentration play critical roles in achieving the best growth performance in fish.

The Use of an In Chemico Digestibility Assay to Reduce the In Vivo Fish Bioaccumulation Testing of Nanomaterials.

Currently for engineered nanomaterials (ENMs), there are no alternatives to bioaccumulation testing in fish as prescribed by OECD TG 305. New approaches are being sought, in order to reduce the numbers of animals used and address the ethical concerns associated with the use of vertebrates in such testing. This study aimed to demonstrate the value of an alternative method - the in chemico digestibility assay - as a tool to assess the bioaccumulation potential of ENMs. Titanium dioxide ENMs, or their equivalent bulk form, were incorporated onto a commercial fish diet and the fish digestion process was simulated in vitro at pH 2 (simulated stomach phase) and pH 7.8 (simulated intestinal phase). Only the 1000 mg/kg dry weight feed treatment showed measurable Ti release in the stomach phase, with the results being similar for the TiO2 ENM and the bulk form. More Ti from TiO2 was released from the feed during the intestinal phase of digestion compared to the stomach phase, but there were no statistically significant differences between either the ENM or bulk form. There was higher incidental Ti release from untreated control feed in the intestinal phase compared to the stomach phase. On a percentage basis, the stomach generally showed a statistically significant digestibility of around 3% of the total Ti in the feed, compared to around 7% in the intestine. The in chemico digestibility assay shows potential for use in the determination of the bioaccessible fraction of ENMs, and could be a useful screening tool to identify ENMs of concern for bioaccumulation.

GROWTH AND SURVIVAL OF SPINY LOBSTER, Panulirus homarus JUVENILES FED WITH DIFFERENT FORMULATED FEEDS

Article Highlights- Indonesia has remarkable natural resources of spiny lobster Panulirus homarus and an exceptional opportunity to establish the largest lobster aquaculture industry in the world.- However, culturing lobsters still relies on natural feeds (trash fish of fresh fishery by-catch) which are inefficient and environmentally unsustainable.- Developing formulated feed based on locally available ingredients is invaluable for replacing natural feeds to support sustainable lobster culture.- Formulated feed made of local fish meal provided the best growth of juvenile spiny lobster Panulirus homarus compared to imported fish meal. AbstractSeveral studies suggested that good growth performance and survival of lobster juveniles can be achieved by feeding the lobsters with formulated feeds. This study aimed to (1) evaluate the growth and survival of spiny lobster Panulirus homarus juveniles fed with different diets having profiles based on a basal diet formulation and (2) to compare the growth of lobsters fed with an identical formulated feed with variations only in sources of fish meal and dry matter content. The feeding experiment was designed following a completely randomized design (CRD) with five diet treatments and five replicates for each treatment. Five experimental diets were prepared in this experiment, i.e., Diet A (basal diet prepared as moist pellets); Diet B (moist pellets with the same formulation as Diet A, using local fish meal); Diet C (moist pellets with the same formulation as Diet A, using imported fish meal); Diet D (dry pellets with the same formulation as Diet A, using imported fish meal); and Diet E (fresh fish). Juveniles of spiny lobster with an average weight of 3.00±0.07 g were allocated in 25 net cages (60 x 60 x 60 cm) placed in a circular HDPE canvas tank (7.5 m in diameter) at a density of 15 lobsters/cage in a flow-through seawater system. The juveniles were fed with the experimental diets twice/day for 12 weeks. The experiment showed that the best growth was observed in juveniles fed with moist feed containing local fish meal (Diet B) with the final weight reaching 18.74±2.30 g. Moist feed containing imported fish meal (Diet C) resulted in a higher survival rate (46.66%), and the lowest survival rate (13.33%) was obtained from juveniles fed with fresh fish (Diet E).

The effect of dietary fish oil replacement by microalgae on the gilthead sea bream midgut bacterial microbiota

The effect of dietary fish oil replacement by microalgae on the gilthead sea bream midgut bacterial microbiota

Variation in basal sources contribution to the diet of a predator fish in an altered flood pulse area in the Amazon

Variation in basal sources contribution to the diet of a predator fish in an altered flood pulse area in the Amazon

Supplementation of sea buckthorn (Hippophae rhamnoides L.) oil in the diets of freshwater rainbow trout (Oncorhynchus mykiss W.) led to enhanced growth and better meat quality.

In this study, sea buckthorn oil (SBO) was added to rainbow trout fish diets at 0.25%, 0.5%, and 1% rates in order to determine the effects on growth, feed conversion rate, survival rate, fillet quality, and physiological, biochemical and histopathological parameters. The experiment was designed in four groups with three replicates each including 20 fish with 18 ± 3g and lasted for 45days. Fish were fed three times a day and weighed biweekly. At the end of the experiment, significant differences were determined with respect to specific growth rates (SGR), weight gains (WG), and feed conversion ratios (FCR) (P < 0.05), except for survival ratios (SR) (P > 0.05). Sea buckthorn oil improved fish fillet quality and weight gain rates by up to 27% compared to control. The pepsin, amylase, lipase, and trypsin enzyme activities differed significantly (P < 0.05) from those of the control group. Serum lysozyme myeloperoxidase (MPO) and plasma nitro blue tetrazolium (NBT) levels differed significantly (P < 0.05) in the 0.5% and 1% groups compared to the control group, except for the 0.25% group. Liver catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) levels significantly differed in all groups, especially in the 0.5% and 1% groups compared to the control group (P < 0.05). SBO supplementation to feed caused significant changes in the FA profiles, especially 18:00 in ∑SFA; 16:1 in ∑MUFA; 20:5n-3 and 20:2n-6 in ΣPUFA; 20:5n-3 in ∑n-3; and 20:2n-6 in ∑n-6 in rainbow trout (P < 0.05). There were no histopathological changes between the control and the experimental groups. The determined data suggested that 1% SBO may be successfully used as a feed additive in rainbow trout.

004 Dietary fish oil eliminates skin inflammation via decreasing Serpinb3b and Slc25a5 and increasing Cacna2d1

004 Dietary fish oil eliminates skin inflammation via decreasing Serpinb3b and Slc25a5 and increasing Cacna2d1

Influence of caffeic acid and Bacillus coagulans supplementation on growth, digestive enzymes, immune response, and antioxidant gene expression in common carp (Cyprinus carpio) and its resistance to Aeromonas hydrophila infection

Present study aimed to investigate the efficacy of dietary supplementation with caffeic acid and Bacillus coagulans on growth performance, digestive enzymes, and immunity of common carp (Cyprinus carpio), and also fish resistance against Aeromonas hydrophila. Fish (21.0 ± 0.5 g) divided into four groups: control group (CD, commercial basal diet), caffeic acid (CA, 5 g/kg feed), B. coagulans (BC, 2×107 CFU/g feed), and CA+BC (5 g/kg + 2×107 CFU/g feed) for 8 weeks, followed by a 14-day challenge with A. hydrophila. A significant enhancement was obtained in growth performance of all treated groups compared to CD (P < 0.05). Also, feed conversion ratio was significantly reduced in treated fish compared to CD group (P < 0.05). Fish of BC and CA+BC groups revealed an increase in activity of amylase, lipase, protease, trypsin, and chymotrypsin in the intestinal tissue. In addition, amylase, lipase, protease, and trypsin in CA group exhibited a higher activity than CD (P < 0.05). A lower decrease in aspartate aminotransferase and a higher increase in alkaline phosphatas were observed in BC and CA+BC groups than CD group (P < 0.05). Values of total protein, total immunoglobulin, lysozyme activity, and alternative complement pathway (ACH50) were higher in sera of BC and CA+BC groups than CD (P < 0.05). Additionally, expression of genes related to lysozyme, IL-1β, IL-8, TNF-α, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in liver tissues of treatment groups were upregulated better than CD (P < 0.05). Furthermore, a significant reduction in mortality was observed in treatment groups compared to CD under the A. hydrophila challenge. These results exhibited that including a combination of caffeic acid and B. coagulans as functional dietary supplements in diet favors common carp health status and growth and, thus, can be recommended in the fish diet.

Forage ecology of Neotropical fish in Brazilian biomes using stable isotopes

Neotropical regions are responsible for harboring most of the global diversity of freshwater fish, providing essential ecosystem services for society. Human activities (e.g., land use changes) jeopardize aquatic ecosystems as well as species, communities, etc., impairing ecosystem services. We investigate the impact of human disturbance on the foraging ecology of Neotropical freshwater fishes across five Brazilian biomes by stable isotope analysis. We analyzed carbon (δ13C) and nitrogen (δ15N) isotopic compositions of Neotropical fishes, sourced from the SIA-BRA dataset. Fishes were categorized into herbivores, omnivores, and carnivores. We tested the correlation between human disturbances, indicated by the human disturbance index (hdi), and changes in fish diets. We expected that the assimilation of C4‑carbon from exotic forage would increase with higher disturbance levels, while δ15N levels would similarly rise due to nitrogen input from anthropogenic sources. We found increases in fish δ13C with human disturbance increases, suggesting greater assimilation of C4 carbon in places where native vegetation was replaced by C4 sources, confirmed by isotopic mixing models. In contrast, δ15N values did not show a significant relationship with human disturbance, probably due to the complex interactions and multiple sources of nitrogen in disturbed environments. Our finds suggest that stable isotope analysis provides a powerful tool for monitoring the effects of landscape changes on aquatic food webs. Particularly, the δ13C values of detritivorous fish that feed on C4 plant detritus could serve as bioindicators of environmental degradation. However, a specific isotopic characterization of each site would be valuable for more accurate niche information.

Vitamin D3 supplementation alleviates lipid accumulation, lipid metabolism disorder, and oxidative stress caused by a high-fat diet in juvenile black seabream (Acanthopagrus schlegelii)

This study investigates the potential of dietary vitamin D3 (VD3) to counteract the adverse physiological effects of a high-fat diet (HFD) in marine fish. Five isonitrogenous diets were formulated: a control diet (∼ 12 % lipid, Control), a HFD (∼ 18 % lipid, HFD), and HFDs supplemented with increasing levels of VD3 (6000, 12,000, and 18,000 IU/kg), referred to as HFD+6000VD3, HFD+12000VD3 and HFD+18000VD3, respectively. The actual VD3 contents in each diet were 10,400, 10,500, 18,100, 26,300 and 33,700 IU/kg, respectively. A total of 450 juvenile black seabreams (Acanthopagrus schlegelii) with an initial body weight of 5.39 ± 0.01 g were used in an 8-week feeding trial. Results showed that VD3 supplementation significantly up-regulated the expression level of cyp2r1, down-regulated the expression level of cyp24a1, and dramatically increased the expression level of vdrb, leading to higher 1,25(OH)2D3 levels in serum and liver (P < 0.05). Compared to the HFD, fish fed diets supplemented with VD3 exhibited reduced TG and TC levels in serum and liver, decreased expression levels of lipogenesis-related genes (aco3, fas, scd1, srebp-1c) and significantly enhanced the expression levels of lipolysis-related genes (hsl, pparα, lpl, atgl) (P < 0.05). Additionally, dietary VD3 supplementation significantly reduced serum AST and ALT activities (P < 0.05), and decreased the size and number of hepatic lipid droplets and vacuoles (P < 0.05). Furthermore, dietary VD3 inclusion decreased oxidative stress biomarkers, enhanced antioxidant enzyme transcription via the Nrf2 pathway, up-regulated antioxidant genes (cat, nrf2β, Cu-Zn sod), and reduced serum and liver MDA content, alleviating oxidative stress. In conclusion, dietary VD3 supplementation effectively mitigated HFD-induced hepatic fat deposition and lipid metabolism disorders in black seabream.

Assessment of the nutritional impact of substituting fishmeal with enzymatically hydrolyzed jojoba meal (Simmondsia chinensis) in the diets of Nile tilapia, Oreochromis niloticus

Enzymatic hydrolysis is a technology that is widely used to enhance the biological and functional characteristics of plant proteins and deactivate anti-nutritious components. In order to tackle this pressing issue, considerable research has been conducted on plant-based proteins as a potential substitute. This study sought to comprehensively examine the impacts of replacing fish meal with enzymatically hydrolyzed jojoba meal (EHJM) in the Nile tilapia, Oreochromis niloticus diets. After the enzymatic hydrolysis process for jojoba meal, hydrolyzed amino acid content increased in enzymatically hydrolyzed jojoba meal (EHJM), while fiber content, phytic acid, saponins, and trypsin inhibitors dramatically decreased. A thorough evaluation of key parameters included growth, gene expression, digestive enzyme activity, digestibility, intestinal histomorphometry, biochemical indicators, and antioxidant enzyme activity. Fish (n = 360, 6.41 ± 0.05 g fish−1) were allocated at random to four groups consisting of four replacement levels of fishmeal protein content with EHJM: 0 % (control diet), 25 % (EHJM25), 50 % (EHJM50) and 75 % (EHJM75) for 74 days. The results showed both the control diet and the EHJM25 groups showed remarkable improvements in performance metrics such as final body weight, specific growth rate, weight gain, feed conversion ratio, and protein efficiency ratio, with no discernible variations between them. The inclusion of EHJM up to 50 % produced a noteworthy (P < 0.05) rise in the intestinal lipase and amylase activities. Furthermore, a high apparent digestibility coefficient for crude lipid and protein values was observed in EHJM25% and EHJM50%. The presence of EHJM up to 25 % in tilapia diets, as a substitute for FM, had a significant impact (P < 0.05) on various parameters in the intestine, including goblet cells, muscularis mucosa, villi height, villi width, absorption area, and height muscularis. Moreover, the inclusion of EHJM with different levels in tilapia diets resulted in a noticeable reduction (P < 0.05) in alkaline phosphatase (ALP) and serum alanine aminotransferase (ALT) levels, with fish given the EHJM75% diet showing the lowest amounts in their plasma. In addition, the amount of plasma total protein, albumin, and globulin were found to rise sharply with the escalating replacement of EHJM in fish diet, reaching the highest values in the EHJM25% and EHJM50% diets. Interestingly, the catalase (CAT) and superoxide dismutase (SOD) levels in fish that were given the control diet and EHJM25% showed a remarkable increase compared to the other treatments (P < 0.05). Fish fed EHJM50% diet had the highest glutathione peroxidase and the lowest malondialdehyde levels. In addition, the fish that were fed the control diet exhibited the highest expression of insulin-like growth factor and growth hormone genes, compared to those fed the EHJM25% diet. Based on the results, the EHJM25% and EHJM50% diets were more effective than the EHJM75% diet in improving the efficiency of Nile tilapia. The inclusion of EHJM in Nile tilapia diets had a neutral effect on growth indices compared to a fishmeal diet (control diet). The optimal replacement level is 55.3 %.