@ARTICLE{Imani Baran, author = {Imani Baran, A. and }, title = {Survey of Population Changes and Cercarial Infection of Lymnaea spp Freshwater Snails. in Miyandoab Region, West Azarbaijan Province in 2010}, volume = {13}, number = {7}, abstract ={Background and Objective: Some freshwater snails are intermediate hosts of human and animal parasitic flukes. These snails are considered as the first and often the second intermediate hosts of parasitic trematode larvae. Therefore, survey of the important epidemiologic indexes related to snails fauna makes it possible to gain information about the sources of infection. The aim of current study was to survey of population changes and cercarial infection of Lymnaea spp. and determine involved factors in Miyandoab region. Materials and Methods: Generally, 5 various and perennial habitats of snails were monitored from May to November in 2010. Snails sampling was undertaken by searching each site using a standard method. After transferring and identifying the collected snails, all of them were individually placed into petridishes in order to investigate their cercarial infection by traditional cercarial shedding method. Snails which did not shed cercariae for the first time, were re-examined som other time and cercariae were finally characterized.   Results: Totally, 514 dextral Lymnaea spp. were collected and identified. The highest percentage belonged to the L. stagnalis (63.62%), followed by L. gedrosiana (26.26%) and L. auricularia (10.12%). The overall infection rate was 2.12%. The infections were only observed in L. auricularia with furcocercariae (19.23%) and L. gedrosiana with echinostom cercariae (0.74%). Conclusion: In comparison whit previous study, the major habitats of snails had been dried so as a result, diversity, abundance, distribution and consequently the fauna of lymnaea spp. have been undergone a lot of substantial changes. So, it should be paid essential attention to this adverse occurrence at least with a view to prevent the likely extinction of these aquatic animals. Key words: Population Changes, Cercarial Infection, Lymnaea spp., Miyandoab, West Azarbaijan, Iran   Funding: This research was funded by Research Committee of Tabriz University of Medical Sciences. Conflict of interest: None declared. Ethical approval: The Ethics Committee of Tabriz University of Medical Sciences approved the study.     How to cite this article: Imani Baran A. Survey of Population Changes and Cercarial Infection of Lymnaea spp Freshwater Snails. in Miyandoab Region, West Azarbaijan Province in 2010. J Rafsanjan Univ Med Sci 2014 13(7): 581-96 [Farsi] }, URL = {http://journal.rums.ac.ir/article-1-2300-en.html}, eprint = {http://journal.rums.ac.ir/article-1-2300-en.pdf}, journal = {Journal of Rafsanjan University of Medical Sciences}, doi = {}, year = {2014} }