Abstract

Normal calvings among 527 cows in a Ruakura Research Station herd (No.1) were not evenly distributed throughout the 24 hours. They were most frequent in the early morning (0100 h to 0600 h, 39%) and afternoon (1300 h to 1900 h, 29%). This diurnal pattern was consistent between years. Altering feeding time from 0700 h to either 1600 h or 1900 h did not increase the frequency of daylight calvings. Feeding at 1900 h did produce 2 periods of intensive grazing each 24 h instead of only one. If a beneficial change in calving pattern is to be produced, it may be necessary to disrupt the period when most cows rest (0100 h to 0600 h) by feeding at around 0300 h.

JT, McIntosh, RD McLaren, DH Carr, GW Howe, and FRM Cockrem

Proceedings of the New Zealand Society of Animal Production, Volume 45, , 27-30, 1985