helminth parasites of rhombomys opimus from golestan province, northeast iran.

background: the aim of the study was to determine the helminthic species occurring in great gerbil rhombomys opimus collected from maraveh tappeh, golestan province, northeast iran. methods : during 2010-2011, a total of 77 r. opimus were captured from rural areas of maraveh tap-peh, golestan province, using sherman live traps and examined for infectivity with any larva or adult stages of helminthic parasites. results: overall, 63 r. opimus (81.8%) were found infected with different helminthic species. the rate of infectivity with each species was as follows: trichuris rhombomidis 31.2%, trichuris muris 32.5%, trichuris spp. 10.4%, syphacia muris 2.6%, dipetalonema viteae (acanthocheilonema viteae ) 37.7%, skrjabinotaenia lobata 15.6%, hymenolepis (=rodentolepis) nana fraterna 5.2%, and taenia endothoracicus lar-va 1.3%. conclusion : r. opimus is host for several species of cestodes and nematodes in the study area. the high rate of infectivity with d. viteae indicates the susceptibility of these gerbils to this filarial nema-tode. synchronous infections occurred up to four species of helminthes in one host.