Prevalence of trichostrongylus in sheep in the district Zhob, Balochistan, Pakistan

Sheep population is estimated to be 27.4 million heads in Pakistan (Economic..., 2010), and 12.8 million (48%) of these sheep are raised in Balochistan (Economic, 2011). Heavy economic losses have been reported due to parasitic diseases in livestock in Balochistan. Factors like exposure to parasites and climate trigger the infestation (Durrani, 1991). Khan et al. (1988c) reported 100% sheep internal parasitic infection in upland Balochistan. The prevalence of gastrointestinal nematodes of sheep has been 25.1 to 92% by different studies in Pakistan (Durrani et al, 1981; Khan, 1985).