Ewe maternal behaviour score and lamb survival

Abstract

The relationship between maternal behaviour and ewe productivity was determined by least squares analyses of records for 1 year on 1050 ewes of 6 genotypes and 3 age groups. A 1 to 5 score was assigned to each ewe based on observations during tagging of lambs within 24 h of birth. Maternal behaviour was better (by 0.26 score) in 6-tooth (6th) than 4th ewes which had a score 0.27 units higher than 2th ewes. Maternal behaviour score increased by 0.18 for each unit increase in litter size (range 1 to 4). When the effect of litter size on maternal behaviour was removed, ewe genotype differences in maternal behaviour score were small. Lambs weaned/lambs born, corrected for litter size, age and genotype of ewe, increased by 0.06 for each unit increase in ewe behaviour score. The rate of increase was greater within higher litter sizes. Weight of lamb weaned/ewe lambing was higher for ewes with higher scores for maternal behaviour.