Preliminary Study on Hard Ticks ( Acari: Ixodidae) of Sheep in Some Areas of Thamar Governorate, Yemen

Abstract

The objective of this study was to identify and determine the prevalence of tick species infesting sheep in some areas of Thamar governorate, Yemen. A total of 392 indigenous sheep breeds of either sex and different age were randomly selected and examined for presence of ticks using standard parasitological techniques from December, 2010 to May, 2011. The results revealed that the overall prevalence of tick infestations on sheep was 43.37 %. Of total 875 ticks collected, Seven species of ixodid ticks were identified. The species on hierarchy of overall prevalence abundance were Rhipicephalus sanguineus (13.01%), Rhipicephalus (Boophilus) decoloratus (9.69%), Rhipicephalus evertsi evertsi (5.87 %), Hyalomma marginatum (4.59 %), Amblyomma variegatum (4.34%), Rhipicephalus (Boophilus) annulatus (3.06%), Haemaphysalis sulcata (2.04%). Rhipicephalus (Boophilus) decoloratus species is recorded for first time in Thamar governorate and Yemen as well as. Statistically, there was significance difference (P<0.05) in the prevalence among different species identified. The highest prevalence rate of ticks infestations was recorded in month of May (62.90%); whereas the lower rate in the month of December (26.67 %). Prevalence of tick infestations was influenced significantly (P<0.05%) by Month variation (season). The effect of associated risk factors (determinants) i.e. age, sex, breed of host and area in distribution of ticks was non-significant. Attention should be given to the control and prevention of tick infestations on sheep reared under traditional management in study areas.