Role of neonatal and maternal risk factors in the faecal soiling of lambs

A total of 1300 lambs from eight spring-lambing flocks in the south west of England were studied from birth to approximately six months of age, Within the first week of life a number of variables were recorded including the lambs' birth weight, sex, faecal consistency, 48- to 72-hour immunoglobulin status acid the condition score and extent of faecal soiling (dag score) of the ewe. Between two and six months of age the lambs were inspected every two weeks and their dag score was recorded. The relationship between neonatal and maternal factors and the risk of becoming faecally soiled later in life (defined as a dag score of 3 or more) was estimated by survival analysis techniques and proportional hazards modelling. There was a significant increase in the rate of faecal soiling of lambs that had experienced a period of watery diarrhoea during the neonatal period (adjusted hazard ratio 1.78, P=0.01), and lambs that were born to ewes with a high dag score (adjusted hazard ratio 1.48, P=0.004). The lamb's birth weight was negatively correlated and its age was positively correlated with the rate at which they became faecally soiled, The results are discussed with reference to the determinants of susceptibility to blowfly strike.