en fish disease fish disease پژوهشي Orginal research papers <span class="styletitle1"><i><span style="LINE-HEIGHT: 115% FONT-FAMILY: "Times New Roman","serif" COLOR: black FONT-SIZE: 12pt FONT-WEIGHT: normal mso-fareast-font-family: Calibri mso-bidi-language: FA mso-ansi-language: EN-US mso-fareast-language: EN-US">Chalcalburnus mossulensis</span></i></span><span class="styletitle1"><span style="LINE-HEIGHT: 115% FONT-FAMILY: "Times New Roman","serif" COLOR: black FONT-SIZE: 12pt FONT-WEIGHT: normal mso-fareast-font-family: Calibri mso-bidi-language: FA mso-ansi-language: EN-US mso-fareast-language: EN-US"> from the <i>cyprinidae</i> family is one of the indigenous fish in Gheshlagh Lake of Kordestan, Iran. </span></span><i><span style="LINE-HEIGHT: 115% FONT-FAMILY: "Times New Roman","serif" FONT-SIZE: 12pt mso-fareast-font-family: Calibri mso-bidi-language: FA mso-ansi-language: EN-US mso-fareast-language: EN-US">Ligula intestinalis </span></i><span style="LINE-HEIGHT: 115% FONT-FAMILY: "Times New Roman","serif" FONT-SIZE: 12pt mso-fareast-font-family: Calibri mso-bidi-language: FA mso-ansi-language: EN-US mso-fareast-language: EN-US">is one of the infective parasites among various species of fish and causes gonads atrophy. In this study, after detection of species and age of samples, the effects of this parasite on gonads tissues and sexual maturation of <font size="3"><span class="styletitle1"><i><span style="FONT-FAMILY: "Times New Roman","serif" COLOR: black FONT-WEIGHT: normal">Chalcalburnus mossulensis </span></i></span><span class="styletitle1"><span style="FONT-FAMILY: "Times New Roman","serif" COLOR: black FONT-WEIGHT: normal">were investigated. By seasonal sampling 144 samples were collected. After investigatiing gonad tissue samples, it was clear that, there is a significant difference between the means of male and female gonads maturation rate in infected and non infected samples (p< 0.05). Infection by </span></span><i>Ligula intestinalis </i><span class="styletitle1"><span style="FONT-FAMILY: "Times New Roman","serif" COLOR: black FONT-WEIGHT: normal">can be the reason for lack of gonads maturation. In addition, the abnormal degenerative changes like, absorption follicle, hemorrhage and infiltration of inflammation cells in ovary tissues of infected fish were seen. In testicle tissue, dispersed hemorrhage, atrophy and MMC (melano-macrophage center) were seen as pathological signs. So the spread of this parasite in different water sources is important as the point the maintenance of native species and cultivated fish</span></span><span class="styletitle1"><span style="FONT-FAMILY: "Times New Roman","serif" COLOR: black"><strong>.</strong></span></span></font></span> 85 94 http://jifro.ir/browse.php?a_code=A-10-1-63&slc_lang=en&sid=1 A. Parsa Khanghah a.parsa@iausdj.ac.ir 10031947532846001087 10031947532846001087 Yes M. Mojazi Amiri 10031947532846001088 10031947532846001088 No I. Sharifpour 10031947532846001089 10031947532846001089 No B. Jalali Jafari 10031947532846001090 10031947532846001090 No A. A. Motalebi 10031947532846001091 10031947532846001091 No