Evaluation of anthelmintic treatment in calves from dairy region of Muriaé, MG, Brazil

Abstract

In five dairy farms from the Muriaé region, MG, Brazil, the effect of anthelmintic treatment on the counts of eggs per gram of faeces (EPG) was studied in 188 Holstein x Zebu calves with four to ten months of age and naturally infected. Each two weeks, ten animals by farm were randomly choosed to perform EPG counts and coprocultures. The anthelmintic treatments were selected at the 600 EPG level and some of them at random by the farmers. The treatments consisted of febendazole by oral route. A 33,3 to 100,0% EPG reduction was observed. There were lower EPG counts in faeces of calves from two farms which had less territorial extension. The gastrointestinal nematodes were Cooperia, Haemonchus, Oesophagostomum, Bunostornum and Trichostrongylus. The fast reinfections of treated animals were probably related to the animals, management and to the climatic conditions of the region which limited the efficiency of the program used.