An inquiry into the causes of liver damage in lambs.

The lamb slaughter records of a large private abattoir showed that a small minority of farms had a lamb liver rejection rate exceeding 40 per cent. Small sheep farms were most likely to have high rejection rates and farms producing both lambs and pigs had relatively high lamb liver rejection rates. In a farm survey statistical analysis showed that the spreading of pig slurry, access to the grazing land by hunts and the infrequent use of dog cestocides were factors significantly linked to high lamb liver rejection rates. A survey of 4000 lambs' livers confirmed the importance of Cysticercus tenuicollis as a cause of rejection. Fifty-two per cent of the livers had lesions which could not be identified but showed histological similarities to ascarid lesions.