Enhancement of Growth in Nile Tilapia, Oreochromis niloticus (Linnaeus, 1758) Through DNA Transfer

Background The Nile tilapia, Oreochromis niloticus is a widely cultivated fish throughout the world. The fish is particularly important for aquaculture in Nigeria due to its popularity. Most of the improved tilapia strains were developed through local selection and crossbreeding. The objectives of this study are to investigate the growth performance, proximate composition and DNA fingerprint and genetic variation of O. niloticus containing foreign fish DNA. Methods A study was conducted to enhance the growth performance of the fish by transferring purified DNA into the fish's somatic tissue. Different concentrations of DNA (0, 10, 20, 30, and 40 µg/µl) extracted from the Nile perch ( Lates niloticus ) were injected into the somatic tissue of the tilapia fingerlings. The injected fish were then raised for 120 days in a polyethylene mobile fish pond (2.5 x 1.5 x1.2 deep). Results Fingerlings injected with 40 µg/µl have significantly (P < 0.05) better final weight, weight gain, average daily weight gain, specific growth rate crude protein and ether extract, and metabolizable energy. Gel electrophoresis revealed distinct banding patterns, suggesting differential integration or expression of L . nioloticus DNA fragments among the treated fish. The number of effective alleles (Ne), Shannon's Information Index (I), Expected Heterozygosity (He) and Unbiased Expected Heterozygosity (uHe) were observed to be high in fish containing higher concentration of the L. niloticus DNA. RAPD analysis indicated that each fish exhibited unique banding patterns, indicating complete genetic variation among the treatments. Conclusion Fragmented DNA materials from Lates niloticus can potentially improve growth in Oreochromis niloticus and support the hypothesis that DNA transfer from Nile perch can significantly alter the proximate composition of Nile tilapia, especially by enhancing protein content and metabolizable energy. These changes could offer nutritional, economic, and production benefits in aquaculture, though further investigation into safety, long-term performance, and consumer acceptance is essential.