Genetic resources of Nile tilapia (Oreochromis niloticus Linnaeus, 1758) in its native range and aquaculture

Nile tilapia (Oreochromis niloticus) is the third-most important fish species in global aquaculture. Its farmed production has experienced a sharp rise in the last two decades, and it is among the top aquaculture species of choice for addressing the problem of food security in many developing countries. Africa holds the wealth of its natural genetic resources, however its aquaculture production is dominated by Asian countries. Native wild Nile tilapia populations in Africa have contributed to development of fast-growing aquaculture strains, and also hold strong potential for further development of new strains with desirable aquaculture traits. The genetic diversity of natural populations in Africa has not been fully characterized, and faces a serious threat of loss due to habitat degradation, pollution, unsustainable utilization of water resources and introgressive hybridization with non-native strains and congeneric species. In this review, topics pertinent to Nile tilapia native genetic resources in Africa, its aquaculture production, progress in genetic improvement of cultured strains and application, threats to native populations in the wild, and conservation strategies for sustainable utilization of natural genetic resources are addressed.