| dry areas: an example of seasonal evolution of helminth infection of sheep and goats in southern mauritania. | a total of 647 faecal egg counts and 53 necropsies were performed on sheep and goats originating from three sites of a sahelian region of mauritania (gorgol) over a period of 2 years (1990-1992). haemonchus contortus, oesophagostomum columbianum and stilesia globipunctata were the most prevalent species. the seasonal pattern was characterized by long survival of adults and high percentages of arrested fourth-stage larvae in the dry season, suggesting that two different strategies were used to su ... | 1995 | 7732638 |