Abstract

During the serious outbreak of facial eczema (FE) in 1989, blood samples were obtained from first-lactation heifers born in 1986, in order to study any genetic influence on the incidence of FE. Heifers were located in 60 herds in Northland (14 herds), Auckland (25) and Taranaki (21). The herds were members of the New Zealand Dairy Board's 1985 Sire Proving Scheme for young Jersey bulls. Samples were collected from 1523 heifers, the daughters of 57 young Jersey sires and 19 other Jerseys including reference sires from previous years. Blood samples were analysed for gamma-glutamyltransferase (GGT), an indicator of liver damage such as due to FE. Overall, 28% of animals had elevated GGT values (>=30IU/1), and 72% (43) of herds had 2 or more animals with elevated GGT. After setting aside data from the 17 herds where no elevations of GGT concentration were recorded, the heritability of log e GGT was 0.31

RL, Baker, P Shannon, DJ Garrick, HT Blair, and BW Wickham

Proceedings of the New Zealand Society of Animal Production, Volume 50, , 197-210, 1990