Survey on the Distribution of Tick Species in and Around Assosa Town, Ethiopia

摘要

In this study, the distribution and abundance of bovine tick species in Assosa town was studied over a period of four month from December 2009-March 2010. Adult ticks were collected from seven main body sites of 384 local cattle which were under extensive management system. A total of 4163 adult ticks collected from half body part were identified, in which two species belong to Amblyomma and one species belong to each in genus of Boophilus and Rhipicephalus , of all the total tick collections, Boophilus, Amblyomma and Rhipicephalus constituted 45, 39.4 and 15.6%, respectively. The tick species encountered were Boophilus decoloratus (45%), Amblyomma coherence (24.4%). Rhipicephalus evertsi evertsi (15.6%) and Amblyomma variegatum (15%). The burden of ticks on cattle by their age group (3 year) had statistically significant difference (p<0.05), with mean = 1.7, 7.8 and 16.9 tick/head, respectively in the study area. The study result indicates that the favorable predilection sites of Boophilus species are dewlap, back and hoof, Amblyomma species are found most of the time on ventral body part and hoof, because of long mouth part. Adult Rhipicephalus evertsi evertsi had a strong predilection site under tail as well as anovulval areas. The sex ratio of all tick species identified during this study periods were skewed towards male except for Boophilus decoloratus . In conclusion the infestation of ticks during the dry season is less then that of rainy season during which the activity of adult ticks becomes high.