Abstract

Artificial insemination (AI) is widely used throughout New Zealand dairy herds because it is convenient and allows herd owners to utilise semen from intensively selected genetically superior sires. The future focus of AI use will be to synchronise oestrus in maiden heifers and cows to further concentrate seasonal calving patterns. There will also be continued use of progesterone-based treatments to stimulate ovarian activity in anoestrous cows and to increase pregnancy rates in inseminated cows. Aspects of behaviour and marked seasonality in red deer and fallow deer currently present challenges to increasing the use of AI and controlled breeding in these species. It would be preferable to have fawning/calving in spring instead of summer, with or without the use of AI. However, the semen production of stags is best from 4 weeks after the onset of the induced or normal rut. This potentially increases the dependence on deep frozen semen and increases the need for the uterine deposition of sperm to increase sire coverage and achieve satisfactory pregnancy rates. Controlled use of hormones will produce altered calving/fawning dates and developing semen collection/processing techniques will increase the use of AI in deer.

PM, Harris, GC Waghorn, and J Lee

Proceedings of the New Zealand Society of Animal Production, Volume 50, , 81-90, 1990