Abstract

The efficiency of winter feed use for weaner calf production was compared in a yearling heifer mating system compared to a 2 year old first mating system in traditional and dairy x beef cows. These computer modelling analyses illustrated, with yearling heifer mating compared to 2 year old first mating, that the total weight of calf weaned per unit of winter feed required is increased by only 2% (Angus dams) and 6% (Hereford x Friesian dams, HxF). With HxF dams compared to Angus dams, the total weight of calf weaned per unit of winter feed required was increased by 8% (2 year old first mating) and 13% (yearling heifer mating). Yearling heifer mating rather than 2 year old first mating within a traditional beef cow breed is questioned, when compared at the same winter feed requirement. The superiority of dairy x beef breeding cows on the basis of calf production from winter feed is confirmed by this analysis. Furthermore, this superiority is maximum when yearling heifer mating is also adopted.

CJ, Wilde, AJ Clark, M Kerr, CH Knight, M McClenaghan, and JP Simons

Proceedings of the New Zealand Society of Animal Production, Volume 51, , 225-226, 1991