The viability of a formulation of the fungus Monacrosporium thaumasium (Drechsler, 1937) was evaluated for the biological control of bovine gastrointestinal nematode parasites. Two groups of seven female calves each, Holstein ´ Zebu crossbred, four to six months of age, were placed in Cynodon dactilon pastures. In group A, each animal received via oral 20g of pellets of M. thaumasium twice a week during a four-month period that began with the onset of the rainy season (October, 2001). In group B (control), the calves did not receive any treatment. The counts of eggs per gram of faeces (EPG) for animals of the group B were significantly greater (P<0.05) than those for animals from group A and the difference of the EPG between the animals from groups A and B at the end of the experimental period was 88.8%. Cooperia was the most prevalent genus. It is concluded that the use of this dose and the periodicity of application of M. thaumasium pellets were efficient in the control of bovine gastrointestinal nematode parasites.
bovine; biological control; Monacrosporium thaumasium; natural enemy; nematophagous fungi
