REGULATION OF EGG PRODUCTION, WORM BURDEN, WORM LENGTH AND WORM FECUNDITY BY HOST RESPONSES IN SHEEP INFECTED WITH OSTERTAGIA CIRCUMCINCTA

摘要: Following infection with Ostertagia circumcincta there was considerable variation in worm burdens, size and number of inhibited larvae even among sheep matched for age, sex, breed, farm origin history parasite exposure. There also substantial the concentration mast cells, globule leucocytes, eosinophils, IgA-positive plasma cells parasite-specific IgA abomasal mucosa. With exception faecal egg counts over time, parasitological immunological traits were all continually distributed animals did not fall into discrete high low-responder categories. The responses correlated. Sheep more had greater amounts Female length strongly positively correlated eggs utero. Faecal associated burden negatively leucocytes mucosa, suggesting that numbers are regulated by immediate hypersensitivity reactions. Decreased female an increased local response to fourth stage larvae. burden. results suggest mature is due, at least part, which regulate fecundity reactions burdens.