Role of ruminants in the epidemiology of Echinococcus granulosus in Tabriz area, Northwest of Iran.

Hydatidosis is a widespread zoonotic disease with a worldwide distribution. This disease produces significant financial losses and it remains a serious health problem in a number of countries. Hydatidosis results from ingesting the eggs of Echinococcus granulosus, and the developing larvae envelop themselves in a cyst which forms in the organs of the intermediate hosts. The aim of this study was to investigate the prevalence of cystic echinococcosis in sheep, cattle, buffalo, and goats, slaughtered in the Tabriz Abattoir, Northwest of Iran. From April 2012 to April 2013, out of 14828 slaughtered animals examined for CE (hydatidosis) in liver and lungs (5000 sheep, 6125 cattle, 1103 buffaloes and 2600 goats), 25.57% were infected. The rates of CE in lungs and liver were 15.2% and 7.18% in sheep, respectively, 15.30% and 9.73% in goats, respectively, 18.71% and 9.61% in cattle, respectively and 15.68% and 11.24% in buffaloes, respectively. The infection rate was higher in lungs and was more pronounced in cattle (P<0.05). There were significant differences found in the prevalence rates of the various ruminants, and also between the sexes (P<0.05). The findings of the present study revealed that lungs were the main infected tissue, and male animals were less likely to be infected than female animals. The infection rates of the different ruminants increased significantly with age, (P<0.05).