Genetic correlations between production traits and components of reproduction in merino sheep

Abstract

Data from the Sheep Genetics database was used in investigation of the genetic relationships between components of reproduction and traits which may be useful indirect selection criteria for reproduction rate in Merino sheep. Pre-joining weight as well as fat and eye muscle depth were favourably genetically correlated with all reproduction traits except ewe rearing ability, as were more favourable scores for maternal behaviour, wrinkle and face cover. Correlations with prejoining condition score were only significant when unadjusted for live weight. Maternal behaviour score was favourably correlated with all reproduction traits except ewe rearing ability but the standard errors were large, and more data are required to improve the precision of estimates. These results suggest that these traits could be recorded by breeders and included in the genetic evaluation system to improve the accuracy of selection for reproduction rate in Merino sheep.