1. Ameliorative role of camel protein hydrolysates diet against alkaline stress in Oreochrmis niloticus: Hematology, immune responses and their regulating genes expression, and histopathological assays.
- Author
-
Alsubaie N, Ibrahim RE, Bawahab AA, Mohamed AA, Abd-Elhakim YM, Khamis T, Osman A, Metwally MMM, Alotaibi BS, and Ghannam HE
- Subjects
- Animals, Protein Hydrolysates pharmacology, Gene Expression Regulation drug effects, Stress, Physiological drug effects, Fish Diseases immunology, Fish Diseases prevention & control, Hydrogen-Ion Concentration, Spleen drug effects, Spleen pathology, Animal Feed analysis, Camelus, Diet veterinary, Cichlids immunology
- Abstract
This investigation looked at the ameliorative role of camel whey protein hydrolysates-diet (PH) in Oreochromis niloticus stocked under alkaline conditions. One hundred sixty fish (16.02 ± 0.14 g) were allocated equally into four groups with four replications for 30 days. The first (control) and second (alkaline) groups were fed basal diets and maintained in fresh and alkaline water, respectively. The third and fourth groups were fed on a PH diet (basal diet containing 75 g PH/kg) and maintained in fresh water and alkaline water, respectively. The hematology, immune-antioxidant indices, immune-regulatory genes, histopathological investigation of the spleen, and resistance to Aeromonas sobria were investigated. The results showed that the alkaline condition induced hematological disorders (lowered red blood cells, hemoglobin, packed cell volume, and white blood cell count) and immunosuppression (lowered phagocytic activity and index, lysozyme, nitric oxide, and complement 3) in the exposed fish. Alkaline exposure induced oxidative stress through elevation of the malondialdehyde and reduction in the antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, glutathione S-reductase, and reduced glutathione). The immune modulatory genes (tolls like receptor-5, interleukin-1beta, interleukin-6, interleukin-8, interleukin-10, interleukin-17, nuclear factor kappa beta, and tumor necrosis factor-alpha) were down-regulated by exposure to alkaline conditions. The microscopic section of the spleen of the fish subjected to alkaline conditions showed notable hyperplasia of the melanomacrophage centers, besides vascular congestion, endothelial cell hypertrophy, and mild hypercellularity in the erythroid and lymphoid elements. In addition, few sections manifested more pronounced erythroid hyperplasia than the lymphoid one. The survival of the fish subjected to alkaline conditions was reduced during the A. sobria challenge. Feeding on a PH diet, the hematology was restored and the immune-antioxidant functions were modulated. Modulation of the immune-regulatory genes and increased survivability of the alkaline-exposed fish were noticed when fed on the PH diet. Consequently, we can recommend enriching the Nile tilapia diet with a 75 g PH/kg diet especially when reared under alkaline conditions to support the immune functions of the fish., Competing Interests: Declarations. Ethics approval: This study has been authorized by the Zagazig University Authority for Animal Use in Research (ZU-IACUC/2/F/393/2023), and all applicable institutional standards were followed when caring for and using animals in this study. Consent to participate: All authors have participated in this work. Consent for publication: All authors review and approve the manuscript for publication. Conflict of interest: The authors declare that they have no conflict. Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer Nature B.V.)
- Published
- 2025
- Full Text
- View/download PDF