Immunity to Ostertagia ostertagi.

Control of ostertagiasis is a major economic problem in the temperate areas of the world. An immunological control scheme for cattle is an important aspect of integrated control and its achievement is dependent on our understanding of how immunity is acquired. Also, host mechanisms regulated by Ostertagia need to be understood in order to address immunological questions. Little is known about acquired immunity to Ostertagia infection in cattle. The degree of immunity is incomplete and its development slow. Evidence is accumulating for impairment of antibody and cellular immune responses by Ostertagia which is responsible for the survival of the parasite in the young host. Other experimental work suggests that local factors, such as eosinophil accumulation, mucosal mast cell kinetics and other cellular and humoral immune responses, may play a role in pathogenesis and immunity. At the present time these areas are also totally unexplored in the study of Ostertagia infection.