Anu, S. JayaramSoundararajan, CRavi Latha, BhaskaranSenthilkumar, TMATANUVAS2019-11-192019-11-192019http://krishikosh.egranth.ac.in/handle/1/5810135720TNV_IJSR_2019_25(2)242-246Theileriosis is an important haemoprotozoan disease of sheep and goats in tropical and subtropical regions caused by the different species of Theileria (Altay et al., 2007). It is mainly transmitted trans-staidly by various tick vectors of family Ixodidae and cause heavy economic losses (US$ 62 million) to livestock (Li et al., 2014). T. lestoquardi is the most important and highly pathogenic species causing malignant theileriosis in sheep (Friedhoff, 1997). In addition, two newly reported species (T. luwenshuni and T. uilenbergi) from China are also pathogenic to small ruminants (Ahmed et al., 2006; Yin et al., 2007). The other species like T. ovis, T. separata and T. recondita are non-pathogenic in small ruminants (Altay et al., 2007; Alessandra and Santo, 2012). General ly, the diagnosis of smal l ruminant piroplasmosis is based on microscopic examination of blood and lymph node smears and clinical symptoms.enVeterinary ScienceArticle