¹Naxçıvan Devlet Üniversitesi, Tebietşünaslık Fakültesi, Zoologiya Bölümü, Naxçıvan MR - AZERBAYCAN
²Nahçıvan Devlet Üniversitesi, Tıp Fakültesi, Eczaçılık ve Stomatologiya Bölümü, Naxçıvan MR - AZERBAYCAN DOI : 10.9775/kvfd.2017.18033 This study was carried out in vitro and in vivo to determine the therapeutic effects of Thymus kotschyanus and Thymus collinus in the territory of Nakhchivan Autonomous Republic against the gastrointestinal parasites in sheep. Essential oils and extracts of these plants were used as antihelminthic preparation in the research. An antihelminthic effect was determined against helminth species (Trichostrongylus axei, Nematodirus abnormalis, Trichocephalus ovis, Haemonchus contortus) collected from the digestive system in in vitro conditions. Furthermore, in vivo conditions, the antihelminthic effect against gastrointestinal helminthes in naturally infected sheep was investigated. Comparing to the control group in the in vitro conditions, helminthes were killed in a shorter time in the experimental groups. In vivo conditions, the antihelminthic effect of Th. kotschyanus essential oil was 88.1% and 82.9% of Th. collinus essential oil. The antihelminthic effects of the extracts prepared from these plants were 69.1% and 63.5%, respectively. The result obtained from Th. kotschyanus volatile oil preparation was 21.6%, the result of Th. collinus volatile oil preparation was 23.2% which was more specific than the first one. The results of the study show that both herbal oils and extracts can be used in the treatment of gastrointestinal parasites of sheep by preparing antihelminthic preparations. Keywords : Thymus kotschyanus, Thymus collinus, Gastrointestinal parasite, Antihelminthics