Background: We investigated the variations of heamathologic and biochemical parameters with different parasitic burdens and the correlation between fecal egg counts and fluke number in livers of sheep naturally infected with .
Methods: In order to detect excretion of eggs, fecal samples from 120 sheep of different age groups were collected individually at slaughterhouse in Neyshabur County in Razavi Khorasan Province during December 2013 - October 2014. Hematologic and blood biochemical values in 120 sheep naturally infected with were compared with equivalent values in 120 parasite-free sheep from an organically farmed flock.