[Fluorescent microscopy in the diagnosis of Dictyocaulus infection in sheep]

Fluorescence microscopy was employed to study Dictyocaulus infection in 15 experimentally infected lambs each given 2000 D. filaria larvae. Studied were also the sera of 10 control lambs and of 20 sheep and goats infected with other helminths. Antibodies were established after the 14th day in 53 per cent of the lambs, the 20th day in 86.6 per cent, and the 27th day in all animals infected with the parasite. Antigens were found mainly in the wall of the digestive and reproductive organs, and in the cuticle of the larvae. As a method of early diagnosis fluorescence microscopy is simple, precise, and readily applicable in establishing Dictyocaulus infections.