The effect of calving season on milk production. A system
study.
S.C. Garcia, F.J. Cayzer, C.W. Holmes and A. MacDonald
Department of Animal Science, Agricultural Services, Massey
University, Palmerston North, New Zealand
Proceedings of the New Zealand Society of Animal Production. 1998,
58: 61-63
A 3-year trial is being conducted at No1 Dairy Farm, Massey
University, to compare the effect of calving season on the whole system
of production, and the results of the first year are presented here.
Three different systems were implemented by stocking each farmlet (40
ha) with Friesian cows which calved either in Autumn (A), in Spring (S)
or 50% in A and 50% in S (A/S). Average stocking rate (SR) was 2, 2.25
and 1.95 cows per ha, respectively. A larger area was conserved as
silage in A than in A/S and S, which also affected pasture growth rate
in Spring. More supplements (t DM/cow) were fed in A (1.2) than in A/S
(0.8) or in S (0.4). The higher yield of milk solids (MS) per cow for
cows which calved in Autumn compensated the lower stocking rates of
those herds and resulted in similar levels of production per ha (705-725
kg MS) for all three systems. These first year results suggest that
similar levels of production per ha can be achieved with different
calving systems and they emphasise the importance of farm systems
studies as a research tool.
Keywords: NZSAPAB;
calving date; milk production; farm comparison; dairy system.
Last Updated 12-09-1998
