Tick-borne diseases of sheep and goats caused by Babesia, Theileria or Anaplasma spp

Abstract

A review is given on the Babesia, Theileria, and Anaplasma species infecting sheep and goats. B. ovis is the most important disease agent. It is transmitted by Rhipicephalus bursa, R. turanicus, Hyalomma anatolicum excavatum, and probably by R. evertsi evertsi B. ovis is widely spread in southern Europe, the Middle East, and central Asia. Its geographical distribution in South and East Asia and in Africa is widely unknown. B. motasi obviously represents several nosodemes in separate regions. It is not pathogenic for intact sheep in northern Europe, whereas it is probably more pathogenic than B. ovis in India and northern Africa. The known vectors of B. motasi are Haemaphysalis punctata and R. bursa. Theileria hirci is transmitted by H. a. anatolicum but occurs outside the distribution area of this tick. Malignant theileriosis of sheep and goats is an important disease in Iraq, Iran, and India. An attenuated macroschizont vaccine is successfully being used in Iran. Anaplasma ovis is transmitted by R. bursa and probably other ticks in the Old World and by Dermacentor andersoni in the New World. A. ovis is widely spread in the Old World. Outbreaks occur only under extreme conditions. The identity of the tick-borne disease agents of sheep and goats and of their vector ticks is uncertain in many regions of the Old and the New World.