Climate Resilience, Nutrition, Breeding and Chemical Inputs in Farmed Nile and Blue Tilapia (Oreochromis niloticus and Oreochromis aureus): A Critical Narrative Synthesis

Abstract

Nile tilapia (Oreochromis niloticus) and blue tilapia (Oreochromis aureus) underpin one of the fastest-growing segments of global finfish aquaculture, yet the literature describing their environmental physiology, nutrition, genetic improvement and chemical management has developed along largely separate disciplinary tracks. This review integrates evidence across these four domains to evaluate how far current knowledge supports resilient, efficient and safe tilapia production under intensifying climatic and market pressures. Peer-reviewed studies and selected institutional sources addressing thermal, hypoxia and salinity physiology, alternative feed ingredients, selective breeding and genomic tools, and the use of hormonal, antimicrobial and other chemical agents were identified through structured searching of open scholarly indexes and synthesised thematically rather than catalogued study by study. The evidence indicates that both species possess substantial but asymmetrically distributed physiological plasticity, with O. aureus offering superior cold tolerance and O. niloticus dominating global production because of faster growth and better-established breeding infrastructure, most notably the Genetically Improved Farmed Tilapia lineage. Nutritional research demonstrates that fishmeal can be partially replaced by plant and insect-derived proteins without proportionate loss of growth performance, although outcomes vary with inclusion level, processing and life stage in ways that limit generalisation. Genetic and genomic approaches have clarified sex-determination architecture and enabled marker-assisted and genome-wide selection, but climate-resilience traits remain comparatively underexploited as selection targets. Chemical inputs, particularly 17α-methyltestosterone for masculinisation and antimicrobials for disease control, remain operationally important yet are associated with environmental persistence, resistance selection and residue concerns that are unevenly monitored across producing regions. The synthesis identifies interactions among these domains, including trade-offs between thermal tolerance and growth rate, and between reduced chemical reliance and disease vulnerability, that are rarely addressed jointly in primary research. Confidence in specific numerical outcomes is tempered by geographical concentration of evidence, heterogeneous experimental conditions and limited long-term or multi-generational data. The review concludes that advancing climate-resilient, low-chemical-input tilapia farming will require research designs that treat physiology, nutrition, genetics and chemical management as interdependent rather than isolated variables.