Abstract:

Lamb survival is a key issue for sheep farming operations. The majority of lamb deaths from birth to weaning occur in the first 3 days after birth and range from 5% to 30% for individual sheep flocks. A simplified lamb post-mortem examination (PM) protocol has been developed for use on farm to determine the primary cause of lamb death between birth and 3 days of age. Firstly lamb viability at birth (LDVB) is determined and secondly the lamb death risk being dystocia (LDD), starvation and exposure (LDSE) or other (LDOTHER) is diagnosed. A trained lamb post-mortem practitioner is expected to take between 5 and 10 minutes to complete a post-mortem examination for one lamb using the protocol and decision tool described. The PM protocol is required for large scale use for AgResearch’s gene marker discovery programme. Breeders involved in the Ovita Lamb Survival study are trained to use the post-mortem protocol and can access breeding values for the lamb mortality traits derived from PM: that is lamb viability at birth (LDVB), lamb death risk due to dystocia (LDD) and lamb death risk due to starvation/exposure (LDSE).