Interval from calving to first oestrus in autumn- and spring-
calving herds in the same locality
G.W. Montgomery, G.H Davis and G.A. Hurrell
Invermay Agricultural Research Centre, Mosgiel and Ministry of
Agriculture and Fisheries, Lincoln
Proceedings of the New Zealand Society of Animal Production.
1980, 40: 280-284
Mean post-partum intervals to first oestrus of 38, 31 and 51
days were recorded in three consecutive years in a small herd of autumn-
calving cows. Mean intervals of Angus, Friesian and Friesian x Angus
cows within this herd were 42, 32 and 42 days, respectively.
Considerably longer intervals to oestrus of 90, 88 and 65 days were
recorded in three years in spring-calving Angus cows in the same
locality. Although there was a significant negative relationship
between calving date and post-partum interval to oestrus in spring-
calving cows, no such relationship existed for autumn-calving animals.
As a result of the short intervals from calving to first oestrus in the
autumn herd, the pattern of calving was more concentrated.
Keywords: NZSAPAB;
Last Updated 12-09-1998
