Echinococcus granulosus is a tapeworm whose life cycle includes dogs and other canines as final hosts, while domestic and wild ungulates act as intermediate hosts for the tissue-invading larval stage (metacestode). E. granulosus has a worldwide geographical distribution. Protoscolices and rostellar hooks of E. granulosus are useful for diagnosis and rostellar hook morphometric features may be useful to discriminate E. granulosus and related species. The present study was aimed to determine a more suitable lytic solution and to obtain a clearest vision for performing morphometric studies on the rostellar hooks of E. granulosus protoscolices. Five fertile hydatid cyst samples were collected from sheep in Kirkuk slaughterhouse, Iraq, during June of 2015. According to the results of the present study, proteinase-K lytic solution is the best approach in morphometric analysis to get a clear vision of rostellar hooks and a safer usage in comparison with solutions containing lactophenol (lactophenol, lactophenol blue).
