摘要
The purpose of this study was to isolate and characterize the disease causative bacterial species from commercially important freshwater fish species, Cirrhinus mrigala. For this purpose, diseased C. mrigala samples were collected both from cultured and wild conditions. From sampled fish, extracted gills, liver, intestine and skin were homogenized in PBS buffer. Bacterial isolation was achieved by inoculating samples on nutrient agar plates using the method of pour plate and streak plate. Maximum total bacterial load was found 3.4 × 105. Bacterial isolates were identified using morphological, physiological and biochemical features. Gram stain, motility, catalase, starch hydrolysis, fermentation, Indole, Methyl red, Voges‐Proskauer and Urease tests were performed for identification. In short, isolated bacteria were identified as Escherichia coli, Staphylococcus aureus, Bacillus cereus and Citrobacter freundii. Pathogenicity was confirmed in healthy fish by the use of reproduced isolate through experimental infection to fulfil Koch's postulates. Variations in organ structures were studied by histopathology and changes that were found to be lesions, tissue degenerations, necrotic and haemorrhages. This study will be supportive in formulating control measures for disease prevention and successful treatment for these pathogenic bacteria.
摘要译文
本研究的目的是分离和表征来自商业上重要的淡水鱼种，Cirrhinus Mrigala的疾病造成细菌种类。为此目的，从培养和野生条件中收集患病C.Mrigala样品。从采样的鱼类，提取的鳃，肝脏，肠和皮肤在PBS缓冲液中均化。使用倒板和条纹的方法在营养琼脂平板上接种样品来实现细菌分离。最大总细菌载量为3.4×10 5 。使用形态学，生理和生化特征鉴定细菌分离物。进行革兰染料，运动，过氧化氢酶，淀粉水解，发酵，吲哚，甲基，雾化膏，逆戟粉，尿素试验，用于鉴定。简而言之，孤立的细菌被鉴定为大肠杆菌，金黄色葡萄球菌，芽孢杆菌和酸杆菌弗隆迪。通过使用通过实验感染使用再现的分离物在健康的鱼中确认致病性，以实现Koch的假设。通过组织病理学和变化研究了器官结构的变化，这些变化是病变，组织退化，坏死和出血。本研究将支持制定对这些致病细菌的疾病预防和成功治疗的控制措施。
Sadia Kanwal[1];Khalid Abbas[1];Tanveer Ahmed[1];Sajid Abdullah[1];Huma Naz[2];Muhammad Anjum Zia[3];Zaheer Ahmed[3]. Description of isolated bacterial pathogens from diseased Cirrhinus mrigala[J]. Aquaculture Research, 2021,52(5): 2130-2137