Abstract

A (CA)n microsatellite (MS) in the 5’ flank of the IGF-I gene and an RFLP in the growth hormone (GH) gene were tested for effects on production traits in Australian Holstein-Friesian cattle. Three alleles (127, 129 and 131 bp) at frequencies of 3.7%, 78.9% and 17.4% were found for the IGF-I MS and two alleles, Val12" and Leu127, with frequencies of 18% and 82% were observed for the GH RFLP. The quantitative effect of the markers on milk production traits was estimated from 3,811 lactation records using an animal model. The IGF-I MS had no effect on milk production traits. The Leu127 allele of GH favoured higher production of milk, fat and protein and was dominant to Val1

M. R Shariflou, C. Moran, F. W Nicholas

Proceedings of the World Congress on Genetics Applied to Livestock Production, Volume 25: Lactation; growth and efficiency; meat quality; role of exotic breeds in the tropics; design of village breeding programs; n, , 43–46, 1998