Abstract

The differential allocation of pasture between ewes of different bearing/rearing ranks requires a knowledge of the relationship between herbage allowance, intake and production. Few experiments have been conducted in which responses to different pasture allowances have been examined for triplet-bearing/rearing ewes, particularly under continuous stocking management. Published feed requirements for ewes rearing triplets have often been extrapolated from those defined for twin-rearing ewes (Geenty & Rattray 1987). The sward surface guidelines for feeding single- and twin-bearing ewes have been published and researched under New Zealand conditions (Parker & McCutcheon 1992; Morris et al., 1993a, 1993b; Morris et al., 1994). There is anecdotal evidence for varying lambing performance and lamb growth rates for triplet-bearing/rearing ewes under pastoral grazing conditions. The national average lambing percentage is increasing to beyond 120% (MWIES 2002). The proportion of triplets in flocks lambing above 150% increases at the expense of single-born lambs (Amer et al., 1999). The aim of the research communicated in this paper was to compare ewe and lamb performance in twin- and triplet-bearing/rearing ewes offered various sward height allowances.

ST, Morris, PR Kenyon, DL Burnham, and JM Everett-Hincks

Proceedings of the New Zealand Society of Animal Production, Volume 63, Queenstown, 152-154, 2003