Reproductive Performance of the Three-Spotted Tilapia, Oreochromis andersonii, Founder Populations

Sustainable aquaculture in sub-Saharan Africa depends on the reliable supply of native Tilapia fingerlings, as reliance on exotic strains threatens biodiversity through hybridization and ecological competition. This study aimed to assess the reproductive performance of three founder populations of Oreochromis andersonii maintained in captivity for varying durations, to inform selective breeding and fingerling production strategies. A total of 513 fish from the NARDC population (over 10 years in captivity), Super Upper Zambezi (SUZ; 5 years), and Luangwa (LUA; 8 months) were reared in sex-segregated hapas under standardised conditions and later bred in intra-population pairs in smaller breeding hapas at a 2:1 female-to-male ratio. LUA fish had the lowest final body mass and condition factor, while NARDC and SUZ were similar and significantly higher. Although the gonadosomatic index varied across groups, pairwise differences between LUA and the other populations were not statistically significant. LUA exhibited the lowest relative fecundity and hatchability but had the highest percentage of females that spawned. These findings suggest that longer domestication periods improved body mass and hatchability, supporting NARDC and SUZ as suitable sources for immediate fingerling production. However, LUA’s higher spawning participation highlights its potential role in maintaining reproductive traits and genetic diversity within selective breeding programs.