Screening for Indian Isolates of Predacious Fungi for Use in Biological Control against Nematode Parasites of Ruminants

Four isolates of predacious fungi, two each of Arthrobotrys oligospora isolated from a sheep and a male crossbred calf and of Duddingtonia flagrans isolated from a sheep and a female buffalo in western India, were studied for their suitability as biocontrol agents against parasitic nematodes of ruminants, using growth assay, predatory activity, germination potential and ability to survive passing through the ruminants gut as criteria. The study showed that isolates of D. flagrans grew well in artificial media, had encouraging predatory activity, produced profuse chlamydospores that germinated easily at 25°C and could survive passage through the ruminant gut. The ovine isolate of D. flagrans was superior in all respects to the isolate from buffalo and was the most promising candidate for biological control of nematode parasites of ruminants.