Genetic parameters for body weight and carcase traits in Australian based south African meat Merino sheep

Abstract

To breed for improved growth and carcase characteristics accurate genetic parameters are required. Heritabilities and genetic and phenotypic correlations for weaning weight (Wwt), post weaning weight (Pwt), yearling weight (Ywt), post weaning fat depth (Pfat), yearling fat depth (Yfat), post weaning eye muscle depth (Pemd) and yearling eye muscle depth (Yemd) were estimated for 4,614 South African Meat Merino lambs. These lambs descended from 124 sires and 1326 dams. Heritability estimates for Wwt, Pwt, Ywt, Pfat, Yfat, Pemd and Yemd 0.33 (0.04), 0.38 (0.04), 0.74 (0.06), 0.19 (0.05), 0.32 (0.06), 0.29 (0.05) and 0.35 (0.07), respectively indicate that these traits are moderate to highly heritable. Significant maternal effects were not found for these traits. There was no evidence to suggest that the genetic parameters for South African Meat Merino sheep differ significantly from those estimated in Merino sheep.