Five years use of Syncro-Mate B in a dairy herd : effect on fertility and milk production

Abstract

Fecundity has important and economical consequences in dairy herds. This can now be improved effectively using techniques that control sexual cycles. One of these, Syncro-Mate B, was tested for five years in a large dairy herd, to study the long term effects of treatment on reproduction and milk production. In this herd, the mating period was from the 15^th of December to the 1^st of March and cows which were not pregnant after this period were systematically removed from the herd and replaced with heifers. The fertility after induced oestrus was more than 50 % and only 14% of the cows did not calve. Average prolificacy was 113 % and fecundity 96 %. Most of the cows (95 %) calved during a three month period. It is therefore possible for the farmer to produce calves and milk to coincide with high market prices. Milk production before treatment was approximately the same as that of the control group (> 6 000 kg/cow). After five years this increased by 100 kg/year. This treatment, at low cost per animal, could effectively improve production and working conditions for the farmer without adversely affecting long term fertility and genetic consequences.