Pishchalenko, M. A.Yevstafieva, V. O.Gorb, O. O.Yasnolob, I. O.Піщаленко, Марина АнатоліївнаГорб, Олег ОлександровичЯснолоб, Ілона ОлександрівнаЄвстаф’єва, Валентина Олександрівна2019-02-252019-02-2520182519-8521https://dspace.pdau.edu.ua/handle/123456789/3393Size parameters of the embryonic development stages ofS. westeri have significant differences and depend on the substrate and the developmental stage. The process of embryogenesis of S. westeri in vitro has four stages: blastomere cleavage, larval formation, mobile larva formation, and release from egg; the stages have morphometric and significant size changes. Embryonic development of S. westeri occurs at 20 to 30 °С in 4–6 hours, and average survival rates is 87.7%.Strongyloides westeri (Ihle, 1917), a parasitic horse nematode, has an unusual lifecycle, which allows it to exist for a long time in the environment. Morphometric features of eggs, larvae and free-living S. westeri were studied in vitrounder different temperature regimes. The optimal temperature for their embryonic development is 25 °С, under which 90% of the first stage rhabditiform larvae are formed and released within 7 hours of cultivation. The temperatures of 20 and 30 °С are less favorable for their development.enStrongyloideshorseslarvaebiological propertiesmorphometryArticle