Genetic and non-genetic factors affecting lamb growth and carcass quality.

Abstract

The work undertaken under this project concerned the effects of genetic and non-genetic factors on lamb growth, both pre and post-weaning, and carcass traits. The principal objective of the genetic studies was to estimate the performance effects of selecting terminal sires on the basis of the lean meat index (LMI) which is produced for pedigree lambs in flocks that participate in the national Breed Improvement Programme operated by the Department of Agriculture and Food. The merits of the Beltex breed, recently introduced to this country, were also evaluated on comparisons with Texel and Suffolk sires. Estimates of within-breed genetic variation for growth and carcass traits were obtained.