A cross sectional study was carried out from October 2013 to March 2014 in and around Bishoftu town with the objectives of determining the prevalence of major external parasite species of calves, preferred predilection sites and determine the associated risk factors. The calves were selected randomly from small holder farms in and around the town. According to this study; out of 384 calves observationally examined, and identified using stereomicroscope/hand lenses, 126(32.8%) were found infested with one or more ectoparasites species. The major ectoparasites identified were lice 26.8% followed by ticks 13.5% and mites 0.5%. Overall, three genera and one subgenus of tick comprising five species and one species of lice and one species of mite were identified in the study. Among the ticks, Rhipicephalus (Boophilus) decoloratus (7.6%), Amblyomma variegatum (5.2%) and Rhipicephalus evertsi evertsi (2.9%) were the most prevalent and the least identified tick species was Rhipicephalus pulchelus (0.5%). In this study, Linognathus vituli was the solitary species of lice identified and the prevalent (26.8%) among all ectoparasite identified. With regard to mites, Psoroptus ovis was the only mite species identified with a prevalence of 0.5%. The difference in the prevalence of ectoparasite species in male and female calves was not statistically significant (p>0.05). There was significant (p<0.05) association between L. vituli infestation and breed, management system, house cleanness and milk feeding practice. The association between tick prevalence and sex, breed, management system, housing condition, house cleanness, and milk feeding practice of calf was no statistically significant (p>0.05). This study demonstrates that ectoparasites are among the most important health constraints of calves in and around Bishoftu leading to important economic losses and attention should be given to control interventions, developing the knowledge of the farmers and further study on the burden of ectoparasites and their effects on calves was recommended.
Key words: Bishoftu, calf, ectoparasite, prevalence, small holder farms.