Abstract

Herd owners comment that they are having increasing difficulty getting their higher producing, higher Breeding Index (BI) cows to conceive. The reports published on local and overseas data are inconclusive and do not substantiate their concern. A solution to this dilemma would be analyses of contemporary groups within herds with production records stored in the national data base. This would allow for the effects of different feeding practices. Any factor which increased the likelihood of a cow failing to conceive to a first insemination will reduce income by $110/return. If the delay in conception must be rectified by induction, the cost of $320 and increased to $700 if the cow fails to conceive. These changes in income mean that if a herd of 170 cows has its pregnancy rate per breeding reduced from 60% to 59%, the estimated loss would total $955. This emphasises the cost of delays in conception date.

TW, Knight, A Death, T Wyeth, and F Hill

Proceedings of the New Zealand Society of Animal Production, Volume 52, , 311-312, 1992