Abstract：
Monogenean trematodes, particularly those belonging to the Diplectanidae family, are significant metazoan parasites with substantial implications for aquaculture expansion. This study, investigatied the occurrence, prevalence, and pathological impact of Diplectanum spp. in European seabass (Dicentrarchus labrax) across three distinct Egyptian fish farms. During 2021-2022, we sampled 1800 European seabass (Dicentrarchus labrax) from three Egyptian fish farms (600 fish per farm). Farms 1 and 2 used semi-intensive earthen pond systems, while Farm 3 utilized an intensive floating cage system. Employing Clinical, post-mortem, parasitological, and molecular examination technique. Pathological lesions were identified, including skin and gill discoloration, emaciation, and internal organ abnormalities. Seasonal prevalence exhibited significant variations between farms, with highest rates observed in spring and Farm 3 reached an overall peak prevalence of 84.67 %. Parasitological examination distinguished two Diplectanum species morphologically, while molecular techniques exhibited limited specificity. Histopathology unveiled damage to gill, liver, spleen, kidney, and intestine, attributed to Diplectanum haptors including inflammation and internal bleeding, potentially leading to secondary infections. Molecular identification via PCR targeting ITS and 28SrDNA genes, revealing similar band sizes for the two Diplectanum species, indicating limited intraspecific genetic diversity. The study emphasizes investigating parasitic infections\' prevalence and impact in aquaculture, necessitating robust molecular techniques for species differentiation. This study underscores the importance of investigating the prevalence and impact of parasitic infections in aquaculture. It highlights the need for robust molecular techniques to differentiate species. By focusing on Diplectanum spp. infections in D. labrax, the study offers valuable insights into managing parasites in aquaculture effectively.
摘要：
单源吸虫,特别是那些属于外交科的人，是重要的后生寄生虫，对水产养殖扩张具有重要意义。这项研究,调查了事件，患病率,和文凭的病理影响。在欧洲海底（Dicentrarchuslabrax）中，横跨三个不同的埃及养鱼场。在2021年至2022年期间，我们从三个埃及养鱼场（每个农场600条鱼）采样了1800条欧洲鲈鱼（Dicentrarchuslabrax）。农场1和2使用半密集土塘系统，而农场3使用了密集的浮笼系统。采用临床，验尸后,寄生虫学,和分子检查技术。确定了病理性病变,包括皮肤和ill变色，消瘦，和内脏器官异常。季节性患病率在农场之间表现出显著差异，在春季和农场3观察到的最高比率达到了84.67%的总体峰值患病率。寄生虫学检查在形态上区分了两种Diplectanum物种，而分子技术表现出有限的特异性。组织病理学揭示了ill的损伤，肝脏,脾,脾肾,和肠，归因于Diplectanumhaptors，包括炎症和内部出血，可能导致继发感染。通过针对ITS和28SrDNA基因的PCR进行分子鉴定，揭示了两个Diplectanum物种相似的乐队大小，表明种内遗传多样性有限。该研究强调调查水产养殖中寄生虫感染的患病率和影响，需要强大的分子技术来进行物种分化。这项研究强调了调查水产养殖中寄生虫感染的患病率和影响的重要性。它强调了需要强大的分子技术来区分物种。通过专注于外交spp。D.labrax感染,该研究为有效管理水产养殖中的寄生虫提供了有价值的见解。
