(Oreochromis niloticus)على أداء النمو، وأنشطة الإنزيمات الهاضمة والمضادة للأكسدة، والاستجابات المناعية في أسماك البلطي النيلي Pistacia atlantica تأثير زيت

الملخص

The aquaculture industry faces significant challenges in maintaining fish health and productivity while reducing reliance on synthetic chemicals and antibiotics. Plant-derived bioactive compounds have emerged as promising natural feed additives that can enhance growth performance, digestive efficiency, antioxidant defense systems, and immune responses in cultured fish species. This study investigated the effects of dietary supplementation with Pistacia atlantica oil on growth performance, digestive enzyme activities (protease, amylase, and lipase), antioxidant enzyme activities (superoxide dismutase, catalase, and glutathione peroxidase), and immune responses (lysozyme activity, respiratory burst activity, and total immunoglobulin levels) in Nile tilapia (Oreochromis niloticus). A total of 240 healthy Nile tilapia fingerlings with an initial average weight of 25.0 ± 1.2 g were randomly distributed into four experimental groups in triplicate tanks. The fish were fed isonitrogenous and isoenergetic diets supplemented with 0% (control), 0.5%, 1.0%, and 1.5% P. atlantica oil for 60 days. Growth performance parameters including weight gain, specific growth rate, feed conversion ratio, and protein efficiency ratio were evaluated at the end of the feeding trial. The results demonstrated that dietary supplementation with P. atlantica oil significantly improved growth performance parameters in all treatment groups compared to the control group, with the 1.0% supplementation level showing the most pronounced enhancement. Digestive enzyme activities were significantly elevated in fish fed diets containing P. atlantica oil, indicating improved nutrient utilization and digestive efficiency. Antioxidant enzyme activities were substantially enhanced in the treatment groups, suggesting that the bioactive compounds present in P. atlantica oil effectively mitigated oxidative stress and strengthened the cellular antioxidant defense mechanisms. Furthermore, immune parameters including lysozyme activity, respiratory burst activity, and total immunoglobulin levels were significantly increased in fish supplemented with P. atlantica oil, demonstrating potent immunostimulatory properties. The findings of this study indicate that P. atlantica oil possesses significant potential as a functional feed additive in Nile tilapia aquaculture, promoting growth, enhancing digestive efficiency, strengthening antioxidant defense systems, and boosting immune responses. The optimal supplementation level was determined to be 1.0% of the diet, which provided the most balanced improvements across all evaluated parameters. This research contributes to the growing body of evidence supporting the use of phytochemicals as sustainable alternatives to synthetic additives in aquaculture, with potential applications for improving fish health, productivity, and disease resistance in commercial tilapia farming operations.