Sheep abomasal phytobezoariasis: the effect of breed, season andage with histopathological observations

The prevalence of the latent form of sheep abomasal phytobezoariasis and the effect of husbandry management on this condition were determinedin a survey in and industrial abattoir in Urmia from June 2005 to July 2006. The effect of different age groups and seasons on the prevalence of sheepabomasal phytobezoariasis was also determined. Furthermore, the histological changes in the affected abomasal tissue were also verified. Thebreeds and ages of the sheep were identified prior to slaughter. In the postmortem, the abomasum was examined for foreign bodies, includingbezoars. Tissue specimens were taken from the abomasal body in the affected cases. The annual prevalence of sheep abomasal phytobezoariasiswas 1.95%. The prevalence was highest in the Makuei breed and the lowest in Ghezel sheep. The prevalence was higher in winter compared to otherseasons. The number of phytobezoars per abomasums ranged from one to four. The histopathological changes in the affected cases includedleukocytic infiltration in the mucosal layer, edema, glandular hyperplasia and cystic spaces