This research aimed to optimise the breeding program of Nile tilapia for smallholder production systems . Yield gap is a major problem in smallholder production systems. This research contributes to closing the yield gap.
In this research the PhD student Samuel Bekele identified the most important yield gap factors in Nile tilapia farming. The amount of oxygen that can be dissolved in water is a major environmental factor determining growth in fish. With low oxygen, there is a reduced feed conversion ratio, a ratio which measures the efficiency with which the fish convert animal feed into meat. The majority of Nile tilapia production takes place under smallholder production system where dissolved oxygen is often low.
Genetic correlation between the environment in which the fish are selected and the environment of the smallholder farms in which fish are raised is important to optimizing breeding programs. Breeding programs should select fish that perform well in smallholder production systems.
In his study, Samuel reports genetic correlations for harvest weight, growth and survival in an aerated pond (high oxygen concentrations) and non-aerated pond (experiencing frequent low oxygen levels). The genetic correlations between aerated and non-aerated ponds are less than unity and can be used to improve the breeding program. The study also revealed new traits for selection that can be used in selection for increased resilience of Nile tilapia, grown in non-aerated ponds. This is the most common production system in tropical countries.
This work is an important step towards optimizing Nile tilapia breeding programs and contributes to closing the yield gap in smallholder Nile tilapia farms.
You can access the scientific thesis through this link samuel_bekele_mengistu (globalacademicpress.com)
Samuel’s project is the result of collaboration between the Animal Breeding and Genomics group of Wageningen University and Research and WorldFish. Samuel’s research was supported by a grant of the KOEPON foundation, and the CGIAR Research Program on Fish Agri-Food Systems (FISH) led by WorldFish.
