On the Incidence of Abomasal Parasites in Fat Lambs from the same flock

Abstract

1. To determine the upper limit of the abomasal worm infestation of healthy lambs was the main object of the investigation. The results show that a lamb slaughtered fat before or shortly after weaning and therefore presumably a healthy lamb, may contain up to 2,100 Haemonchus and up to 4,670 Ostertagia.2. Infestation with Haemonchus conlortus is negligible until August.3. Infestation with Ostertagia remains almost steady from early May until mid-September.4. Infestation with Trichostrongylus axei occurs from May until mid-September, but is never a heavy one.5. The evidence suggests, but does not prove, that in mid-summer there is a wide difference in the infestation of single and twin lambs.6. The results, so far as they affect the seasonality of infestation are, strictly speaking, applicable only to the flock of the Duthie Experimental Stock Farm, but are probably true for the North-East area of Scotland.