Abstract

In a CSIRO Sheep Heterosis Experiment, 387 F^ ewes were mated 
to either purebred, F1 or F2 rams for studying the effect of male 
heterosis on several lamb production traits and to investigate 
pro rata retention of male heterosis based on the dominance 
hypothesis. Evidence was found to demonstrate the occurrence of a 
moderate effect due to the F1 rams (versus the purebreds) and the 
dominance hypothesis appeared adequate to account for the pro rata 
retention i.e. at 50%, of heterosis in the F2 rams.

T. S Ch'ang, R. Evans

Proceedings of the World Congress on Genetics Applied to Livestock Production, Volume IX. Breeding programs for dairy and beef cattle, water buffalo, sheep, and goats., , 547–552, 1986