Abstract

Supplementation of a ryegrass/white clover pasture diet with pasture silage is a common management practice in New Zealand dairy herds. The effect of this supplementation during early lactation on reproductive performance has not been investigated. Five herds of 20 cows were formed before calving commenced on June 1 1992. From August 5 to September 4, two of these herds were fed 5 kg dry matter/cow/day of pasture silage in addition to the ryegrass/white clover pasture offered to all herds. Pasture silage supplementation did not alter the intervals from calving to first ovulation, first oestrus, or to conception. However, it reduced the first service conception rate(37.5% vs 53.3%; (sed = ± 10.0%), for pasture and silage and pasture only cows; respectively). A positive effect on reproductive performance of pasture silage supplementation was not demonstrated in this trial

S, McDougall, DA Clark, KL Macmillan, and NB Williamson

Proceedings of the New Zealand Society of Animal Production, Volume 54, , 95-98, 1994