Indirect genetic effects for harvest weight in Nile tilapia (Oreochromis niloticus)

Abstract Text: An indirect genetic effect (IGE) is a heritable effect of an individual on the trait values of other individuals it interacts with. A bivariate analysis of harvest weight and survival was conducted by fitting an animal IGE model in ASReml to data from the GIFT strain. The estimated total heritable variation was 0.32±0.09. We observed substantial contribution by IGEs to the total heritable variation. The negative direct-indirect genetic correlation, -0.38±0.19, indicated low competitive phenomena in GIFT population. The results obtained in this study, coupled with the evidence from livestock, suggest that the inclusion of IGEs in selection decisions will help increase aquaculture production and at the same time promote fish welfare due to less competition in the population.

Keywords:

indirect genetic effect

harvest weight

competition

Nile tilapia