Thesis:

Investigating the infection with liver parasites in slaughter animals in Sabzevar city in the first half of ۲۰۲۵.

Effective disease control primarily requires adequate information on disease transmission patterns in endemic areas, and this issue is further complicated by intraspecific variation in parasites. The present study was designed to investigate the level of liver parasite infection in slaughtered livestock in Sabzevar County in the first half of 1404. In this study, the level of infection with some parasites in livestock slaughtered in the Sabzevar County slaughterhouse was examined over a 5-month period. Based on the results, out of 16,377 slaughtered livestock, the percentage of slaughtered livestock was 14.82%, 15.16%, 19.25%, 18.75%, and 32.01% of them were slaughtered in the months of Farvardin, Ordibehesht, Khordad, Tir, and Mordad, respectively. The highest frequency of livestock slaughter took place in the month of Khordad (1,553 female livestock and 3,684 male livestock). According to the results, about 6.15% of slaughtered female sheep and 0.96% of slaughtered male sheep were infected with hepatic hydatid cyst. Also, the rate of parasitic infection with hepatic hydatid cyst in female and male goats was 1.90% and 2.14%, respectively, and in female and male cattle was 7.28% and 0.98%, respectively. The prevalence of Fasciola in male sheep was 8.90% and the prevalence of Dicrocelium in male sheep was 1.96%, which was the highest infection among the slaughtered livestock. The rate of infection with hepatic hydatid cyst in female and male sheep in June was 11.40% and 1.09%, respectively, and the infection with hydatid cyst in female and male sheep in May was 4.94% and 0.95%, respectively. Fasciola infection was 2.63% and 8.39% in female and male sheep in June, respectively. The results also showed that there was a significant relationship between the incidence of parasitic infection and the gender of the slaughtered animals.

Keywords: Livestock infection, parasitic infection, slaughterhouse, fasciola, sarcocyst, hydatid.