Reproductive Performance and Short-Term Growth Pattern of The Progenies of the Reciprocal Hybrids of Clarias gariepinus and Heterobranchus bidorsalis

Global food-fish production based on capture from the wild, natural resource is now known to be limited in its capacity in meeting the demands for fish protein. This is evidentially due to degradation of the aquatic environment, increasing global population and resultant pressure on aquatic resources and increased dietary advices recommending the consumption of more fish visa-vis livestock flesh (Thustean and Roberts, 2014) and aquaculture is the viable alternative. Aquaculture production in Nigeria has witnessed increased production in the last two decades, growing 14.24 times from 1998 to 291,233 tons in 2018 (FAO, 2018; Adeleke et al., 2021). This growth is driven by the declining capacity of the nations’ natural fishery resource to meet the demand for fish and destruction of critical habitats, discovery of candidate aquaculture species, population growth, changing dietary patterns, removal of regional barriers to movement of goods and services, development of new technologies and innovations resulting in intensification among others. From year 2000, Nigeria’scontribution to global aquaculture production increased marginally from 0.07% to 0.44% in 2015. Currently, Nigeria is the leading producer of farmed fish in sub-saharan Africa and second to Egypt in Africa (Adeleke et al., 2021).

To improve growth and sustain the successes recorded in the industry, production of fast growing strains are needed. Hybridization is a breeding technique used to generate genetic diversity from different individuals of different species, genus or populations of the same species. The aims of hybridzation include improving growth performance, flesh quality and tolerance to adverse rearing environmental conditions; increasing disease resistance, producing sterile animals, and manipulating sex ratios as well as various other traits. The technique is also a viable alternative to selective breeding when there is little additive genetic variation in the desired traits of pure stocks to be exploited. Intergeneric hybridization is the crossing of different species belonging to different genus with the aim of producing offspring that will exploit heterosis and combine useful characteristics of both species. However, hybrids must be properly characterized, identified and classified (Akinwande et al., 2013). Part of the phases in intergenerc hybridization is the morphological description of the resulting hybrids. The detailed characteristics of the morphometric features of the hybrids between C. gariepinus and Heterobranchus species may be needed to distinguish it from the different species within the clariidae. The aim of this study is to compare the short-term growth, survival, and morphological characteristics of the progenies of the early stage of reciprocal hybrids of Clarias gariepinusx Heterobranchus bidorsalis. It is expected that the present study will generate information that will contribute to the development of Nigerian aquaculture.