Abstract

The DairyNZ Whole Farm Model was used to predict the effect of temporary once-a-day (OAD) milking during the calving period on milksolids (MS) production, farm profitability and herd body condition score (BCS) at dry-off. Farms from three regions and three independent seasons were modelled for: wholeseason twice-a-day (TAD) milking of all cows (Control), OAD milking of all cows for eight days immediately post-calving and TAD milking thereafter (Col OAD), OAD milking of the herd for three weeks from the planned start of calving (PSC) and TAD milking thereafter (3 wk OAD), and OAD milking of the herd for six weeks from the PSC and TAD thereafter (6 wk OAD). Model outputs indicated MS production (kg/ha) losses of 2, 1.2 and 3.7% and profit ($/ha) losses of 6.5, 4.5 and 11.6% for the Col OAD, 3 wk OAD and 6 wk OAD regimes, respectively. Slight improvements in dry-off BCS were predicted for the OAD milking regimes, comparedwith the control. Milking the herd OAD for three weeks from the PSC may be the prefered strategy to offer labour, lifestyle and animal health benefits with the smallest losses of MS production and farm profit.

EN, Khaembah, AG Rius, PC Beukes, G Levy, P Gregorini, JR Roche, JK Kay, and CVC Phyn

Proceedings of the New Zealand Society of Animal Production, Volume 73, Hamilton, 21-25, 2013