Abstract
Investigations of the histochemistry of calves infected with Oesophagostomum radiatum at 8 and 10 days post-inoculation and with Ostertagia ostertagi at 8 days postinoculation revealed an increase in the reaction for glycoprotein and a decrease in collagen associated with the lesions produced by the larvae of Oes radiatum. Such changes in the chemistry of the tissues were not observed in ostertagiasis. In neither infection were alterations in the distribution and abundance of glycogen and acidic mucopolysaccharides detected at this stage.