A naturally occurring outbreak of sheep scab in a flock of 202 ewes during mid-pregnancy resulted in exudation from the scab lesions and hypoalbuminaemia lasting for two to 10 weeks in the severely affected ewes. The serum albumin concentration at the time of diagnosis and two weeks after treatment with ivermectin was inversely correlated with the severity of the scab lesions (P < 0.001). The loss of body condition score over a period of 48 days after treatment was significantly correlated with the initial severity of the scab lesions (P < 0.001). Despite adequate energy nutrition of the ewes during late pregnancy, the birthweights of lambs born to ewes with severe sheep scab were 10 per cent less than those of lambs born to ewes with mild sheep scab.