Diets For Nile Tilapia Research Articles

Top‐sprayed mixture of phytase, xylanase and β‐glucanase enhances energy and nutrient matrix in all‐vegetable diets for Nile tilapia

This study aimed to evaluate the effects of supplemental phytase with xylanase and β-glucanase blend on the apparent digestibility coefficient (ADC) of gross energy and nutrients, including amino acids, minerals, and nitrogen (N) and phosphorus (P) balance in Nile tilapia, Oreochromis niloticus. Diets were elaborated either without enzyme supplementation (control) or supplemented with phytase (PHY), xylanase and β-glucanase (XB) blend or a combination of phytase plus xylanase and β-glucanase (PHY+XB) blend. Fish (n = 192; 60 ± 3.4 g) were fed with the experimental diets replicated four times. Compared with the control group, fish-fed with the PHY+XB diet showed a higher ADC of gross energy and nutrients, including amino acids and minerals. Also, compared to control diet, digestible energy, digestible protein and available P contents were higher in fish-fed diet PHY+XB by 1.63 MJ kg−1, 7.21 and 4.70 g kg−1 diet respectively. Compared to the control group, fish-fed diet PHY+XB displayed lower total N and P loss of 17.51 and 10.09 g kg−1 of body weight gain (BWG) respectively. The study findings provided new insight into the nutritive value and ecofriendliness/sustainability of diets associated with exogenous enzymes for tilapia culture.

Evaluation of a Commercial High-Protein Distiller’s Dried Grain with Solubles (HP-DDGS) Product in the Diet of Juvenile Nile Tilapia (Oreochromis niloticus)

A comparative feeding trial and digestibility determination were conducted to evaluate the nutritional value of a commercial, high-protein distiller’s dried grains with solubles (HP-DDGS) ingredient in the diet of Nile tilapia (Oreochromis niloticus). For the feeding trial, six diets were formulated to contain 360 g total dietary protein kg-1 and were prepared with incremental levels of protein from the HP-DDGS (0, 75, 150, 225, 300, and 375 g of dietary protein kg-1) replacing protein from fishmeal and soybean meal. Juvenile tilapia ( 10.4 g ± 0.37 ; average initial weight ± SD ) were evenly distributed in 24, 38-L aquaria operated as a recirculating system and fed twice daily to apparent satiation throughout the 8-week trial. Nile tilapia exhibited no significant ( P > 0.05 ) differences in weight gain, feed efficiency, condition indices, whole-body proximate composition, or innate immunological responses when fed any DDGS-supplemented diets compared to the control diet. Percent apparent digestibility coefficients (ADCs) of the DDGS product for organic matter, crude protein, and gross energy were 74.8%, 83%, and 82.8%, respectively. Availability values for all amino acids were 89% or greater. Thus, this high-protein DDGS was established as a readily digestible protein feedstuff suitable for replacing soybean meal and fishmeal at up to 375 g of total dietary protein kg-1 in a practical diet for Nile tilapia.

Bioprocessing post‐consumer food waste for use as a fish feed ingredient

Post-consumer food waste (FW) is a sustainable source of nutrients that could be used as aquafeed ingredient to decrease aquaculture production expenses. However, FW has a relatively low protein content. Bioprocessing can help improve the nutritional composition of FW prior to using it in aquafeed. The present study assessed the potential benefits of substituting part of juvenile Nile tilapia (Oreochromis niloticus) diets with yeast-fermented oil-extracted FW (FWY). Seven isonitrogenous diets (34% crude protein) were prepared, replacing the standard formulation with 0, 15, 20, 25, 30, 35 and 40% FWY. Juvenile O. niloticus (11.07 ± 0.01 g) were size sorted and stocked into 21 tanks. Each diet was randomly assigned to three replicate tanks, and fish were offered their respective diets for 6 weeks. Results suggest that up to 30% of Nile tilapia feed can be substituted with FWY without significant effect on final body weights and lengths, feed conversion ratio, specific growth rate, hepatosomatic and viscerosomatic indices, body moisture, protein and lipid content of fish. Using an inexpensive ingredient such as FWY to replace 30% of traditional aquafeed ingredients is a promising approach towards decreasing aquaculture production cost without compromising fish growth and welfare.

Effect of palm kernel meal (Elaeis guineensis, Jacq, 1763) in the diet on digestive transit and some serum parameters in Nile tilapia (Oreochromis niloticus, Linnaeus, 1758)

As part of the continuation of the thesis work on the valuation of palm kernel cake in the diet of Nile tilapia, a study was carried out from March 7th to April 12th, 2018 at the Aquaculture Research and Development Unit of the University of Lome in Togo. It aims to evaluate the digestive use efficiency of palm kernel cake (PK) in Oreochromis niloticus. So, two lots of 180 male Oreochromis niloticus; juvenile of 57.14 ± 4.43 g and adults of 144.04 ± 7.65 g were each randomly distributed in 9 recirculate system concrete tanks of 600 L, at 20 fish per tank, filled to 250 liters of water. They were fed two weeks with three isoprotein diets (32% crude protein) in triplicate, distributed manually three times a day at 2% of the fish biomass; standard fish feed Raanan (RA) and two diets containing 30% PK untreated (R3) or cooked in water for one hour (R3C). After a 2 days fasting, some fish were fed once again to satiety (8am). Then a sample of 6 fish per lot was euthanized in a clove solution. After blood sampling, the fish were dissected at 0h, 1h, 4h, 8h, 12h and 24h after feeding to measure blood and intestinal parameters. The results obtained show that raw PK is an unpalatable fibrous ingredient but well valued once cooked with a digestive improvement allowing good absorption of food micronutrients in both juveniles and adults. This absorption led to changing in the serum protein level for growth of fish and nitrogenous excretion in the form of urea. The cooking slowed the transit of the food into the digestive tract of tilapia, this can improve zootechnical performance of fish.

A Comparison of the Beneficial Effects of Inorganic, Organic, and Elemental Nano-selenium on Nile Tilapia: Growth, Immunity, Oxidative Status, Gut Morphology, and Immune Gene Expression.

This study investigates the effects of different sources of selenium (inorganic (SSE), organic (OSE), and elemental nano-selenium (NSE)) on the performance of Nile tilapia (Oreochromis niloticus). In total, 204 Nile tilapia fingerlings were randomly divided into 4 equal groups fed 1 of 4 diets: a control (adding no selenium) and 3 diets as selenium sources (1mg/kg diet), After a 65-day feeding trial, the growth performance parameters of Nile tilapia were significantly enhanced by dietary selenium supplementation (P < 0.05), with the highest values recorded in the OSE- and NSE-supplemented groups. The selenium-supplemented groups had the highest packed-cell volume, hemoglobin, and red blood cell levels, with the highest values seen in the NSE-supplemented group (P < 0.05). Innate immune-related enzymes and immunoglobulin levels were significantly enhanced with selenium supplementation (P < 0.05); the NSE group demonstrated the highest significant levels of these enzyme activities (P < 0.05). In all selenium-supplemented groups, malondialdehyde levels were significantly and equally reduced (P < 0.05) compared with levels in the control. Bactericidal activity was only enhanced in the NSE group (P < 0.05) compared with other treatments. The expression of TNF-α and IL-Iβ genes was significantly upregulated in selenium-supplemented groups, with the highest expression in the OSE and NSE groups (P < 0.05). These findings support the importance of incorporating selenium in the diet of Nile tilapia. Furthermore, elementary nano-selenium is more effective than inorganic or organic selenium supplementation at improving Nile tilapia growth performance and overall health.

Effects of Eucalyptus globulus leaf extract on growth performance, feed utilization and blood biochemistry of Nile tilapia, Oreochromis niloticus

The effects of Eucalyptus globulus Labill. extract in diets of Nile tilapia (Oreochromis niloticus Linnaeus, 1758) were studied. Five diets (500 g each) supplemented with 0 ml (T 0), 5ml (T 5), 10 ml (T 10), 15 ml (T 15) and 20 ml (T 20) of E. globulus extract were fed to O. niloticus for 12 weeks. Group fed diet T 10 recorded the highest final weight (42.27 g), weight gain (36.97 g) and specific growth rate (3.72). The highest protein efficiency ratio (2.36), feed efficiency (0.70) and condition factor (1.31) were observed in group fed diet T 10. Compared to fish fed diet T 0, all groups fed E. globulus extract recorded significantly higher levels of crude protein content in the whole body. Hemoglobin concentration increased with increasing levels of E. globulus extract up to T 10 but decreased after further increase in E. globulus extract in diets. Increasing E. globulus extract levels in diets resulted in a significant decrease in aspartate aminotransferase. Group fed diet T 5 recorded the least (17.50) alkaline phosphate and was significantly lower than all other groups. Globulin concentration decreased with increasing E. globulus extract in diets. This study concludes that dietary administration of E. globulus promotes growth performance, feed utilization and increases the main hematological and biochemical parameters of O. niloticus fish. For optimum growth, 10 ml per 500 g (T 10) feed is recommended. This study provides new information on applications of eucalyptus and, at the same time, promotes rational development and utilization of eucalyptus resources.

Clove (Eugenia caryophyllus) essential oil in diets for Nile tilapia (Oreochromis niloticus) improves fillet quality

This study evaluated the effect of including clove essential oil (EOcl) in Nile tilapia diets on animal performance and antioxidant power, lipid oxidation, gene expression, texture, pH, color and sensory analysis in fillets. Three levels of EOcl in the diets were evaluated (0.70, 1.05 and 1.40 g/kg), provided over three periods before slaughtering the animals (15, 45 and 60 days). The antioxidant power in the diets increased after including EOcl. There was an interaction effect between the level and period of inclusion of EOcl on the antioxidant power and lipid oxidation of fillets stored up to 14 days after slaughter. Lipid oxidation was reduced by 43.3% compared with the control group. EOcl inclusion in the diet, regardless of level and period, improved texture and promote less gene expression of catalase and glutathione synthetase. This demonstrates that the antioxidant in the tilapia diet acts against the oxidative stress process. Considering the results for the interactions and parameters evaluated, including 1.05 g/kg of clove essential oil in the rations for 15 days before slaughter is indicated because it contributes to a higher fillet quality.

Utilization and benefits of palm oil in fisheries

Utilization of crude palm oil as a fish feed ingredient has been carried out in recent years. Crude palm oil can replace fish oil on dietary fish. The use of CPO has been applied to barramundi (Lates calcarifer), Rainbow Trout (Oncorhynchus mykiss), Japanese sea bass (Lateolabrax japonicas), salmonid species, and Nile tilapia (Oreochromis niloticus) diets. palm oil appears to boost protein efficiency when being added to oxidized fish feed. The various advantages of palm oil include superior energy sources (saturated and monounsaturated fatty acids), high content of natural antioxidants (carotenes and E vitamin), lessening fatty acid deposition, and low cost and producing high oil yield. Moreover, palm oil-based diets for fish indicated no effect on the fillets either in their texture or color Fish growth is not disturbed if you change fish oil to crude palm oil in fish feed. The level of use of palm oil is different for each fish species.

Digestibilidade de hidrolisado proteico de fígado e carne suínos pela tilápia-do-nilo

Abstract The objective of this work was to evaluate the digestibility of the protein, amino acids, and gross energy of swine liver and meat hydrolysates by Nile tilapia (Oreochromis niloticus). The fish were distributed into 12 tanks with conical bottoms, in a completely randomized design, and fed with the three following diets, with four replicates each: a reference diet with soybean and fish meal; and two test diets, one with swine liver hydrolysate and the other with swine meat hydrolysate. The coefficients of apparent digestibility were high for both hydrolysates, being above 83% for dry matter, 95% for crude protein, and 92% for gross energy. Regarding amino acids, the coefficients remained at 98–100% for the two hydrolysates. The digestibility percentages of the hydrolysates were higher than those of the protein ingredients, both of plant and animal origin, commonly used in the formulation of diets for this fish species. The tested hydrolysates have potential to be used in the formulation of diets for Nile tilapia.

POTENTIAL APPLICATIONS OF DIETARY Moringa oleifera LEAVES AS GROWTH MODULATOR AND IMMUNOSTIMULANT AGAINST Aeromonas hydrophila FOR FARMED Oreochromis niloticus

Herbal medicine, including moringa (Moringa oleifera), is widely used as dietary supplementation to enhance growth performance and increase disease resistance in aquaculture. This study aimed to investigate the effects of supplementing moringa leaves on growth performance, hematology and disease resistance of nile tilapia (Oreochromis niloticus) against Aeromonas hydrophila. Fish (38.05 ± 0.83 g) were fed with a commercial feed supplemented by moringa leaves at 0%, 15%, 20%, and 25%, ad libitum, twice a day for eight weeks. Results revealed that 15% moringa leaves supplemented diet gave the highest weight gain, while the specific growth rate was statistically significantly different (p&lt;0.05) among the treatments. Fish fed with 25% supplementation had the highest total red blood cell count and total white blood cell count. All experimental groups had higher values of red blood cells and white blood cells than the control group. The challenge test with A. hydrophila showed that the fish fed with the 25% moringa leaves supplementation diet had the highest relative percentage survival rate. There were no significant differences among the treatment groups. However, the treatment groups had a statistically significant difference with the control group (p&lt;0.05). Results of the present study indicated that supplementation of 15% moringa leaves in diet gave optimal growth performance, while supplementation of 25% moringa leaves in the diet showed the best results in terms of the health of nile tilapia. Moringa leaves supplemented in nile tilapia diet enhanced growth performance and increased disease resistance against A. hydrophila.

Hematological parameters, liver integrity and growth of Nile tilapia fingerlings fed diets supplemented with propolis extract

Aim of study: To assess the effects of propolis extract supplementation in diets for Nile tilapia (Oreochromis niloticus) fingerlings on growth performance, hematological and histological parameters. Area of study: The study was carried out in Paraná (Brazil). Material and methods: The experimental design was based on six treatments including the control diet and propolis supplementation (2%, 4%, 6%, 8% and 10% in the diet). Three hundred Nile tilapia fingerlings, with an initial weight of 0.61± 0.02 g, were distributed in 30 plastic mesh hapas (0.15 m3 each) arranged in a concrete tank of 25 m3 of water volume. The duration of the experimental period was 90 days. Main results: The increasing levels of propolis did not influence the growth performance and proximate composition of fishes. Red blood cells and hematological indices were not affected by propolis supplementation. However, total leukocytes and thrombocytes were higher in fish fed on propolis diets, being significant in fish fed 2% and 8%, and 6% and 8% supplemented diets groups, respectively. Research highlights: The supplementation of propolis alcoholic extract in the range of 2, 4, 6 and 8% in the diet for Nile tilapia fingerlings promote healthier fish with increased immunity in the evaluated culture conditions.

Impacts of Aegle marmelos fruit extract as a medicinal herb on growth performance, antioxidant and immune responses, digestive enzymes, and disease resistance against Streptococcus agalactiae in Nile tilapia (Oreochromis niloticus)

An experiment was conducted to investigate the effects of Aegle marmelos fruit (AMF) extract on the growth performance, biochemical parameters, immune response, antioxidative capacity, and digestive enzyme activity of Nile tilapia (Oreochromis niloticus). Fish were fed a diet supplemented with AMF at concentrations of 0 (AMF0; control), 5 (AMF5), 10 (AMF10), 15 (AMF15), or 20 (AMF20) g/kg for 8 weeks. The results show that the final body weight, weight gain, specific growth rate, average daily gain, and feed conversion ratio were significantly higher in fish fed AMF15 and AMF20 compared to those fed the control diet (P < 0.05). Moreover, significant increases in antioxidant enzyme activities and non-specific immune responses were observed in groups fed AMF15 and AMF20. Interestingly, the level of cholesterol decreased with increasing AMF concentrations in the diet. As dietary AMF levels increased, digestive enzyme activities significantly improved. After the feeding trial, fish were injected intraperitoneally with Streptococcus agalactiae, and the 14-day cumulative mortality was calculated. A high survival rate after challenge with S. agalactiae was observed in all groups that received AMF-supplemented feed. Therefore, the present study suggests that supplementing the diet of Nile tilapia with AMF at a concentration of 20 g/kg could encourage their growth, improve their immunity and antioxidant status, and provide strong protection against S. agalactiae.

Palm oil in diets for Nile tilapia (Oreochromis niloticus) post-larvae

The objectives of this research were to evaluate the effects of the substitution of soybean oil by palm oil in the diet of Nile tilapia (Oreochromis niloticus) post-larvae, to observe the performance and attractiveness of the feed, and to evaluate the fatty acid methyl esters profile of palm oil. Four hundred Nile tilapias were used after hatching (seven days old), distributed in 20 fiberglass tanks of 20 L each. The experiment was carried out in a completely randomized design with five treatments and four replicates. The treatments consisted of different levels of inclusion of palm oil, which were: 0.0, 1.5, 3.0, 4.5 and 6.0 %. The concentration of monounsaturated and saturated fatty acids in palm oil was measured, resulting in high amounts of palmitic, oleic and linoleic fatty acids. Significant differences were observed for the variables final weight, total length, weight gain, specific growth rate and condition factor. No significant differences were observed for palatability of the diets. It is concluded that the inclusion of 3% or more palm oil in substitution of soybean oil during the masculinization stage of tilapia larvae contributes to the improvement of productive parameters.

Dietary Zinc in Association with Vitamin E Promotes Growth Performance of Nile Tilapia.

Zinc (Zn) and vitamin E (VE) are essential micro-nutrients that contribute a pivotal role in the physiology and nutrition of fish. An experiment was designed to know the effects of Zn and VE addition in the diet on growth and feed utilization in Nile tilapia (Oreochromis niloticus). Four diets containing Zn (80mg/kg), VE (50mg/kg), Zn (80mg/kg) + VE (50mg/kg), and without Zn and VE (control) were fed to Nile tilapia in aquaria with triplicate groups for 6weeks. Survival, growth parameters (weight gain, WG; %WG; specific growth rate, SGR), and feed utilization (protein efficiency ratio, PER; feed conversion ratio, FCR) were calculated at the end of the feeding trial. Several hemato-biochemical parameters (hemoglobin, Hb; red blood cell, RBC; white blood cell, WBC, and glucose) and morphology of muscle were analyzed. The growth parameters (WG, %WG, and SGR) and feed utilization (FCR and PER) improved significantly in the fish fed with Zn, VE, and Zn + VE supplemented diets. There was no significant change in the values of Hb, RBC, WBC, and glucose level among different groups. Significantly improved diameter of muscle fiber, reduced distance between muscle fiber, and increased number of the nucleus and hyperplastic muscle fiber were observed in the fish fed with Zn, VE, and Zn + VE supplemented diets. These results suggested that Zn and VE can be effectively incorporated into the diets of Nile tilapia for better growth with maximum feed utilization.

Use of rice protein concentrates inOreochromis niloticusdiets and its effect on growth, intestinal morphology, biochemical indices and ghrelin gene expression

Fish meal (FM) is a significant source of protein, but the high cost has limited its use in feeds. Hence, alternative, economic and available FM substitutes should be found. In this study, the consequences of replacing FM with rice protein concentrate (RPC) on the growth parameters, proximate body composition, digestive and absorptive capabilities, biochemical parameters and the expression of appetite-related gene (ghrelin) in Nile tilapia, Oreochromis niloticus, were investigated. Fish (27.8 ± 0.1 g) were randomly organized into four groups and fed on experimental diets having four replacement percentages of FM with RPC: 0%, 25%, 50% and 75% (RPC0, RPC25, RPC50 and RPC75) for 5 months. The results cleared that RPC25 group exhibited linearly and quadratically the highest values for growth parameters, growth hormone level, and activities of protease, amylase as well as proximal intestinal villus length, width, the goblet cells count and ghrelin gene expression among all groups. From overall results, RPC could be used as an economically and beneficial ingredient to replace up to 25% of dietary FM in Nile tilapia diet with enhancing the growth performance, digestive and absorptive capability, and health status, but with the supplementation of synthetic amino acids.

Immunomodulatory effects of Yarrowia lipolytica as a food additive in the diet of Nile tilapia

The use of yeasts as a dietary additive for fish can act as a source of nutrients and as an immunostimulant. This work aimed to evaluate the effects of the fermented biomass of the yeast Yarrowia lipolytica as a food additive on zootechnical and hematological parameters, and on immune response in the plasma and kidney of Nile Tilapia (Oreochromis niloticus). After supplementation with 3, 5, and 7% of the yeast biomass for 35 days, the blood and tissues of the animals of each experimental group were collected for analysis. The addition of this biomass in the feed promoted an improvement of zootechnical parameters in tilapia. There was also a rise in the number of neutrophils (groups with 3, 5, and 7%) and monocytes (group 3, 5, and 7%) compared with the control group. Moreover, there was an increase in the levels of lysozyme, myeloperoxidase, and nitrite/nitrate content in the blood of animals fed with yeast biomass. On the other hand, there were no observed alterations in survival and hematological parameters of animals fed with yeast biomass. In the analysis of the kidney, the addition of biomass in feed promoted an increase in levels of myeloperoxidase (group with 3%) but did not alter the levels of lysozyme and nitrite/nitrate content. In conclusion, this study demonstrated that Y. lipolytica had growth and immunostimulatory effects on Nile tilapia. These findings strongly suggest the potential application of a Y. lipolytica-based immunostimulant for tilapia aquaculture.

Aurantiochytrium sp. Meal Improved Body Fatty Acid Profile and Morphophysiology in Nile Tilapia Reared at Low Temperature

Aurantiochytrium sp. is a heterotrophic microorganism that produces docosahexaenoic acid (DHA), thus being considered as a possible replacement for fish oil in aquafeeds. We investigated the effect of Aurantiochytrium sp. meal (AM) dietary levels (0, 5, 10, 20, and 40 g kg−1) on Nile tilapia body and hepatopancreas fatty acid (FA) profile, body FA retention, somatic indices, and morphophysiological changes in the intestine and hepatopancreas, after feeding Nile tilapia juveniles (average initial weight 8.47 g) for 87 days at 22 °C. The 10AM diet was compared to a control diet containing cod liver oil (CLO), since their DHA concentration was similar. Within fish fed diets containing increasing levels of AM, there was a linear increase in n-3 FA content, especially DHA, which varied in the body (0.02 to 0.41 g 100 g−1) and hepatopancreas (0.15 to 1.05 g 100 g−1). The morphology of the intestines and hepatopancreas was positively affected in AM-fed fish. Fish fed 10AM showed less accumulation of n-3 FAs in the body and hepatopancreas when compared to fish fed CLO. Therefore, AM is an adequate substitute for fish oil in winter diets for Nile tilapia, with the supplementation of 40AM promoting the best results regarding intestine and hepatopancreas morphophysiology.

In vitro characterization of Acrocomia totai defatted kernel meal as a novel raw material in Nile tilapia Oreochromis niloticus feed and the effect of exogenous phytase inclusion over nitrogen and phosphorus bioavailability

This work aimed to explore the potential value of the Acrocomia totai defatted kernel meal as an alternative feed ingredient for Nile tilapia (Oreochromis niloticus) diet. In vitro assays were conducted simulating tilapia digestion. Soybean meal was included as a reference and two phytase doses were assayed. After running the gastrointestinal simulations, amino acids bioavailability from soybean meal with phytase addition was higher than in the other treatments. However, when expressed on a crude protein content basis, the relative performance of the treatments with A. totai improved. The protein composition of the raw materials affected their performance because of globulins and specific amino acids such as arginine, lysine and histidine. A higher relative contribution of these last in Acrocomia kernel protein determined their lower compared performance. Phosphorus bioavailability from Acrocomia, expressed on a dry matter basis, was the highest, but increments resulting from phytase addition, expressed on a phytic acid basis, were not significantly different between raw materials. Therefore, no specific affinity between phytase and the raw materials’ phytic acid was evidenced. This study demonstrated that A. totai kernel meal has potential as a protein source in aquafeed but also it has limitations: it is a big phytic phosphorus source that is only available with phytase addition.

Replacing fishmeal with a single cell protein feedstuff in Nile tilapia Oreochromis niloticus diets

There is a growing concern about the use of fisheries-derived proteins in aquaculture. This study was conducted to investigate the effect of either partially or totally replacing fishmeal (up to 15% of the diet) by the inactivated dry yeast product DY-Pro in Nile tilapia Oreochromis niloticus diets. The DY-Pro replaced 0% (DY-PRO0), 2% (DY-PRO2), 5% (DY-PRO5), 25% (DY-PRO25), 50% (DY-PRO50), 75% (DY-PRO75) or 100% (DY-PRO100) of the protein provided by fishmeal in seven isonitrogenous and isocaloric experimental diets, which were fed to the experimental fish (initial average body weight 11.33 ± 1.65 g) for 12 weeks. At the end of the experiment, the graded replacement of 2–100% of fishmeal protein by the DY-Pro did not significantly (P < 0.05) affect fish weight gain or gut length and weight, but linearly (P < 0.05) improved feed and nutrient utilization. Moreover, the DY-Pro did not have any negative impacts on the gastrointestinal tract as shown by histopathology. There were no pathogens or signs of significant metabolic or toxicant-related disease in the epithelium. Results showed that tilapia given diets containing DY-Pro consumed less feed to achieve the same weight gain as tilapia given fishmeal-based diets. Overall, the DY-Pro is a good feed ingredient, which could totally replace fishmeal in Nile tilapia diets and possibly lead to reduced feed costs.

Isatis phytogenic relieved atrazine induced growth retardation, hepato-renal dysfunction, and oxidative stress in Nile tilapia.

The influence of herbicides causes health and economic loss, which requires innovative solutions to sustain the aquaculture industry. In this regard, dietary isatis is included in Nile tilapia diets to relieve atrazine (ATZ)-induced growth retardation, hepato-renal dysfunction, and oxidative stress. The first and second groups offered the control diet (control), while the third and fourth groups offered the isatis supplemented diet (1%). Meantime, half of the water was replaced and mixed with ATZ (1.39 mg/L) in the second and fourth groups for 30 days. The group of fish delivered isatis had significantly enhanced FBW, WG, and SGR, while fish intoxicated with ATZ had meaningfully impaired growth behavior (p < 0.05). Further, the FCR was improved by isatis, and ATZ resulted in the worst FCR among the groups. Interestingly fish fed isatis and exposed with ATZ (88.89%) had a higher survival rate than fish exposed with ATZ without isatis feeding, and both are lower than the control (97.78%) (p < 0.05). The histological structure in the isatis-treated groups showed distinguished enhancement and branching of the intestinal villi. The intestine of ATZ–treated fish revealed damage and inflammatory cell infiltration in the intestinal mucosa with separation of lining epithelium. Generally, fish fed isatis and intoxicated with ATZ had lower uric acid, urea, creatinine, ALT, and AST and higher total protein, globulin, and albumin than fish exposed with ATZ without feeding with isatis (p < 0.05). Markedly, fish-fed isatis had the highest SOD, CAT, GPx, and the lowest MDA level compared to the other groups (p < 0.05). Meanwhile, fish exposed with ATZ had the worst SOD, CAT, GPx, and the highest MDA level compared to the other groups (p < 0.05). In summary, dietary isatis relieved ATZ induced growth retardation, hepato-renal dysfunction, and oxidative stress in Nile tilapia.