Abstract

An experiment was carried out at Tokanui (Te Awamutu) and Wallaceville (Upper Hutt) over 4 years to test for the presence of sire by location interactions for faecal nematode egg count (FEC), using Romney rams from the flocks at these locations selected for high (H) or low (L) FEC. A total of 14 Tokanui rams (8H and 6L) and 12 Wallaceville rams (7H and 5L) were used in their flock of origin in the mating years 1986-90 and then in the other location in 1988-91. There were 491 lambs recorded for FEC at Tokanui, and 875 at Wallaceville. A test of the sire by location interaction was obtained by treating records from the two locations as different 'traits', and estimating the genetic correlation between them. Estimates were made on log transformed FEC from lambs recorded in January and again in March. Fixed effects were included for sire source and contemporary group (genetic group of dam, year of birth of lamb, sex of lamb), and sire was fitted as a random effect. For FEC in January, heritabilities for the two locations averaged 0.39

JC, Pollard

Proceedings of the New Zealand Society of Animal Production, Volume 53, , 183-188, 1993