Abstract

Twin lambs that weighed a minimum of 16 kg (n=134 in 2014 and n=124 in 2015) were randomly allocated to one of three treat-ments: (i) Early weaning (54 and 46 days after the midpoint of lambing in 2014 and 2015, respectively) onto a herb-clover mixed sward (plantain, chicory, red clover and white clover) (HerbEW); (ii) Lambs + dams unweaned on a herb-clover mixed sward until conventional weaning at approximately 13 weeks of age (HerbCW); and (iii) Lambs + dams unweaned on a grass-clover mixed sward until conventional weaning (GrassCW). In 2014, overall greater (P<0.05) liveweight gains were found in HerbCW lambs followed by HerbEW and GrassCW lambs. In 2015, liveweight gains of HerbCW and GrassCW lambs did not differ (P>0.05), but were greater than gains of HerbEW lambs (P<0.05). In 2014, HerbEW lambs that were > 20 kg grew more quickly than HerbEW lambs that were <18 kg (P<0.05). In 2015, HerbEW lambs had similar rate of liveweight gain irrespective of their live weight at treatment allocation (P>0.05). Lambs can be weaned early onto herb-clover mixed swards and achieve greater liveweight gains after wean-ing compared to lambs unweaned on grass-clover mixed sward. Weaning lambs less than 20 kg onto herb-clover mixed sward, however, can result in lower lamb liveweight gain compared to heavier lambs.

WEMLJ, Ekanayake, RA Corner-Thomas, LM Cranston, PR Kenyon, and ST Morris

Proceedings of the New Zealand Society of Animal Production, Volume 77, Rotorua, 37-42, 2017