The anoestrous syndrome in New Zealand dairy cattle. 1. A preliminary investigation

Authors: Macmillan KL, Watson JD, Fielden ED
Publication: New Zealand Veterinary Journal, Volume 21, Issue 5, pp 77-81, May 1973
Publisher: Taylor and Francis

Animal type: Cattle, Livestock, Production animal, Ruminant
Subject Terms: Oestrus/oestrous, Reproduction - female, Reproduction, Diagnostic procedures
Article class: Scientific Article

---

Abstract: New Zealand dairy farming is based primarily on a seasonal system of management whereby the calving pattern of the herd is adjusted so that maximum milk production coincides with the greatest pasture production for grazing. Consequently both mating and calving periods must be restricted and the concept of maintaining a 365-day intercalving interval becomes a major consideration. Both submission rate (the rate at which the individual members of the herd are mated over a defined service period) and conception rate (the rate at which the individual members of the herd mated over a defined service period conceive) are most important in this respect since the average cow must conceive about 83 days after parturition if this intercalving interval is to be maintained. Delays in showing overt oestrus or failures in detection of individuals showing overt oestrus can have a marked effect on overall herd performance and it is these phenomena which are described as the “anoestrous syndrome”. The purpose of this series of papers is to define the problem as it occurs under New Zealand conditions and to demonstrate the relative value of several approaches used in attempts to deal with it. This paper describes some results of preliminary investigations undertaken during the 1971-2 dairying season.

---