Enteric parasitosis in northern Thailand dairy heifers and heifer calves

A cross-sectional study was designed to: (1) determine the prevalences of e nteric parasitic infections in dairy heifers and heifer calves (Bos taurus) in northern Thailand, and (2) determine the risk factors associated with t he observed prevalences of infection. A stratified random sample of 87 farm s was selected for study, and fecal and blood samples were collected from 4 39 out of 450 heifers and heifer calves from these farms. Fecal samples wer e processed by floatation and modified Benedek sedimentation methods, and t hen examined microscopically for the presence of enteric parasitic ova. Com plete blood counts typically were within the reference range (done using st andard methods). The overall prevalence for enteric parasites in heifers an d heifer calves was 54%: most were of trematodes (41%) and nematodes (26%). Risk-factors analysis at the farm level yielded no significant results. In creased age significantly increased the odds of enteric parasite infection (OR = 1.02, 95% CI 1.01-1.04). (C) 2001 Elsevier Science B.V. All rights re served.