en Parasitologiy Parasitologiy پژوهشي Research <div><strong>Introduction:</strong> Dicrocoeliasis is a common disease of bile ducts and gallbladder of domestic and wild ruminants. This disease is caused by different species of <em>dicrocoelium</em> including <em>Dicrocoelium dendriticum. </em>The aim of this study was to identify pathological damages and molecular features associated with this parasite in ruminants.<br> <strong>Materials and Methods:</strong> In this cross-sectional study, 180 fresh adult <em>D. dendriticum</em> worms were collected from 45 infected livers of slaughtered cattle, sheep, and goats in three western provinces of Iran. After histopathological examination, a 963 bp fragment (28S <a>rRNA </a><a href="#_msocom_1" id="_anchor_1" name="_msoanchor_1" uage="JavaScript">[MRT1]</a>&nbsp;gene) was amplified using Polymerase Chain Reaction (PCR). The amplified fragment was digested by Trul1 restriction enzyme to evaluate through Restriction Fragment Length Polymorphism (RFLP) method.<br> &nbsp;<strong>Results:</strong> Based on histological examination, hyperplasia of mucosal glands and swelling of bile ducts of infected livers were observed. In all studied samples, a 963-bp fragment was produced by PCR. Based on PCR-RFLP, the PCR products were digested by Trul1 restriction enzyme producing four fragments (116 bp, 145 bp, 293 bp, and 409 bp) all of which were related to <em>D. dendriticum</em>. Sequencing of the obtained 28S rDNA fragments showed that all of them were completely similar, and comparing them with the Gene Bank sequences showed 97% to 100% similarity between homogeneous fragments. The obtained sequences were registered in the Gene Bank with the accession numbers of MT539114, MT539115, and MT539116.<br> <strong>Conclusion: </strong>According to the present study, <em>D. dendriticum</em> is the predominant parasite infecting ruminants in west of Iran.</div> <div> <hr align="left" size="1" width="33%" > <div> <div id="_com_1" uage="JavaScript"><a name="_msocom_1"></a><span dir="LTR">&nbsp;<a href="#_msoanchor_1">[MRT1]</a></span><span dir="LTR">DNA or RNA?</span></div> </div> </div> Dicrocoelium dendriticum, Pathology, 28s rDNA, PCR-RLFP, Sequencing 43 52 http://jbrms.medilam.ac.ir/browse.php?a_code=A-10-139-2&slc_lang=en&sid=1 Mohammad Hossein Ebrahim Pour hossein.ilam2011@gmail.com 10031947532846004124 10031947532846004124 No Department of Pathobiology, Science and Research Branch, Islamic Azad University, Tehran, Iran Bahar Shemshadi bshemshadi@yahoo.com 10031947532846004125 10031947532846004125 Yes Department of Pathobiology, Science and Research Branch, Islamic Azad University, Tehran, Iran Alimohammad Bahrami am.bahrami@ilam.ac.ir 10031947532846004126 10031947532846004126 No Department of Pathobiology, Para Veterinary Faculty, Ilam University, Ilam, Iran Salome Shirali s.shirali2017@gmail.com 10031947532846004127 10031947532846004127 No Department of Biotechnology, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran