Abstract

Three hundred and fifty farmers involved in the Livestock Improvement Corporation Sire Proving scheme (SPS) were surveyed, in May 1999, on the incidence of Facial Eczema (FE) in their herds. The SPS farmers were asked to score their 2- and 3-year-old SPS daughters on a five point scale; 1=not affected, 2=slightly affected, 3=severely affected (still alive), 4=culled due to FE and 5=died due to FE, and to comment on any calves or yearlings that were in categories 3 to 5. In the herds with at least one case of FE (50% of respondees), 89% of the animals were not affected, 5% were slighty affected, 5% severely affected and 1% were either culled or died primarily from FE. Heritabilities of 3-17% verified that FE in this dataset was controlled in part genetically and with the DNA bank for all SPS daughters, enables a QTL study to be undertaken. The proposed experimental design is an association study with the pooling of DNA for the 516 daughters that were scored 3 or higher. The control for the experiment would be paternal half sibs for each of the ‘affected’ daughters from the same herd, if possible. To detect linkage disequilibrium (LD) a panel of some 1000 microsatellites would be genotyped.

RJ, Spelman, MD Sellars, and K Sanders

Proceedings of the New Zealand Society of Animal Production, Volume 60, Hamilton, 281-283, 2000