Abstract

Data collection was integrated with LIC’s herd testing service using a sample of 102 herds involved in LIC’s SireProving Scheme (SPS) in 1995. In addition to milk volumefrom herd testing, the concentrations of fat, crude protein(total nitrogen), casein, whey and lactose were determined.The data was collected from over 3,000 cows born in 1996and first calving in the 1998 spring season, these beingpredominantly the daughters of approximately 220 SPSbulls. The milk characteristics were measured at three herdtests on each cow, with each herd having a herd test in eachof the Sept/Oct, Nov/Dec and Jan/Feb periods. Hereafter,we refer to these three periods as stages of lactation.

DL, Johnson, SF Petch, AM Winkelman, and M Bryant

Proceedings of the New Zealand Society of Animal Production, Volume 60, Hamilton, 318-319, 2000