Abstract

Production data were collected over 3 years from a flock of 600 mixed-age ewes (approximately equal numbers of Romney, Coopworth and Perendale) shorn either once-yearly in October or twice-yearly in February and October. They were grazed as a single mob throughout the year, except over mating when they were divided into breed groups and joined with rams of their own breed. Twice-yearly shearing depressed total annual greasy wool production but did not affect total annual clean wool production. Twice-shorn ewes weaned 7% more lambs because of a reduction in barrenness. Shearing treatment did not affect live weight either pre-shearing in February or post-shearing in October, nor did it affect ewe and lamb survival. Incidence of casting was less than 1%. Overall economic returns for the 2 groups of ewes were similar with the greater net wool returns of the once-shorn ewes offsetting the greater net returns from the extra lambs weaned by the twice-shorn ewes. Extrapolation of the observed production trends suggested the net returns from once-yearly shearing pre-joining would be greater than the returns from either once-yearly shearing in spring or twice-yearly shearing pre-joining and again in spring.

ML, Tate, and PA Dratch

Proceedings of the New Zealand Society of Animal Production, Volume 48, , 181-186, 1988