An epizootic of besnoitiosis in goats in Fars province of Iran.

Over 100,000 goats were grazing freely in isolated herds of 100 to 600 goats in a mountainous area of more than 2000 km2 to the north-east of Darab City in Fars Province in southern Iran. Twenty to fifty percent of the goats in this area were infected with besnoitiosis. Sheep, cattle and donkeys grazing in the same area showed no clinical manifestations of the infection. The diagnosis of the infection in the clinically suspected animals was confirmed by histological studies on skin biopsies from the ear tips and carpal and tarsal regions, and the distribution of this protozoon in the tissues and organs of this intermediate host was studied by post-mortem and histological examinations. Skin biopsies from the carpal and tarsal areas of 12% of clinically normal goats from the infected area were also lightly infected with besnoitia cysts.