A Seasonal Survey on the Helminths Infections of the Ruminants Slaughtered in the Abattoirs of MazandaranProvince, Northern Iran

Background: gastrointestinal infections in ruminants are a major cause of economic losses. the present study aimed to evaluate the prevalence and seasonal variations of gastrointestinal helminth parasitic infections in the slaughtered animals in mazandaran province, northern iran. methods: this descriptive study was conducted on 300 cattle ruminants (sheep and goats) in mazandaran province during september 2015-march 2017. the animals were assessed using parasitological methods. the contents of abomasa, small intestine, muscles, and liver were evaluated macroscopically and microscopically. results: among 300 ruminants, 178 (59.33%) were positive for various species of gastrointestinal helminthes, including t. colubriformis, o. circumcincta, m. marshalli, h. contortus, habronema spp., p. skrjabini, t. saginata, echinococcus spp., fasciola spp., and dicrocoelium spp. babol was the most infected city (p = 0.001), and spring and summer had higher infection rates. females were significantly more infected than males, and the animals aged more than nine months were infected more commonly than younger animals (p < 0.05). conclusion: according to the results, the rate of gastrointestinal helminth infection was relatively high among the slaughtered ruminants in northern iran in terms of economic and zoonotic importance, which threatens animal production and public health.