QTL for birth weight in Bos taurus cattle

Abstract

Records of birth weight (BW) from a beef cattle experiment in New Zealand and Australia were analysed to test for linkage to DNA markers on all chromosomes except the sex chromosome. This was part of a search for quantitative trait loci (QTL) for production, carcass and meat quality traits. Two extreme Bos taurus breeds, Jersey (J) and Limousin (L), were used to generate over 400 back-cross progeny in each country. There were 5 significant BW QTL, with one on each of 5 different chromosomes, and two other locations where QTL effects approached significance. The effects of sire-derived J and L alleles on progeny BW for significant QTL ranged from -0.84 to 0.73 phenotypic standard deviations, or from -3.13 to 2.73 kg, indicating that QTL from both breeds were associated with increased BW.