刺参(Apostichopus japonicus)保苗期“肠炎病”及其治疗方法

Etiology and Treatment of Enteritis Disease in Cultured Junviles of Apostichopus japonicus

中文关键词: 刺参  肠炎病  哈维氏弧菌  氟苯尼考  治疗方法

英文关键词: Apostichopus japonicus  Enteritis disease  Vibrio harveyi  Florfenicol  Therapeutic method

中文摘要:

      对2014年3月山东省蓬莱某刺参(Apostichopus japonicus)保苗场患“肠炎病”的刺参进行了临床症状和组织病理学观察以及病原菌分离与鉴定，利用氟苯尼考为治疗药品，以脏壁比、增重率和特定生长率为评判指标，探讨了3种不同用药方式(口服、药浴、口服＋药浴)对刺参保苗期“肠炎病”的治疗效果。结果显示，刺参“肠炎病”症状表现为体色发黑，附着能力弱，摄食和活动能力差，解剖后可见肠道内食物不连续，肠腔内有大量黄白色粘液或浓状物质，肠道壁变脆、韧性差且易断裂，显微镜下观察到肠道存在大量细菌；组织病理学显示，患病刺参肠道绒毛膜散乱、粘膜层溃散，结缔组织散乱，且与肌肉层分离较明显。自刺参肠道处分离出优势度最高的细菌In-1菌株，人工感染实验证实，该菌为刺参“肠炎病”致病菌，该致病菌主要来源于饲料藻粉。利用细菌形态观察、生理生化和分子生物学方法(16S rDNA和gyrB)鉴定该菌株为哈维氏弧菌(Vibrio harveyi)。该菌株对头孢三嗪、阿奇霉素、强力霉素和氟苯尼考等12种药物高度敏感。不同用药方式的治疗效果显示，使用氟苯尼考药浴可获得最佳治疗效果，刺参经药浴治疗后增重率达(24.23±0.41)%，特定生长率达(0.77±0.01)%/d。本研究可为刺参疾病防控和健康养殖提供理论依据和技术参考。

英文摘要:

      The cultured juvenile sea cucumber (Apostichopus japonicus) sufferred from "enteritis disease" in a breeding farm in Penglai in March 2014. In this study, the clinical symptoms and histopathology of enteritis disease were investigated. To provide reliable means to control this disease, the pathogen was isolated and identified, and its sensitivity to different antibiotics were tested. The effects of different therapeutic methods (oral, bath, oral with bath) were evaluated using three indices, including the ratio of viscera to body wall (RVBW), weight gain rate (WGR) and specific growth rate (SGR). The results showed that the sea cucumber infected with the enteritis disease displayed dark body color, poor feeding rate, weak motility and adhesion ability. The ingested food in the intestine of sick sea cucumber was discontinuous, and large amount of yellow-white mucus was found in the intestine. The intestinal wall was brittle, poor toughness and easy to fracture. A large amount of bacteria was detected in the intestinal tract under the microscope. The histopathological analysis on infected sea cucumbers revealed the scattered intestinal villus, dispersed mucous layer, scattered connective tissue and obviously separated muscle layers. One dominant bacterium (In-1) was isolated from the infected sea cucumber intestine and was confirmed as the causative pathogen using the artificial infection experiment. The bacteriological analysis indicated that the deteriorated feed (algae powder) was most likely the origin of the pathogen. The pathogen was identified as Vibrio harveyi using morphology observation, physiological and biochemical, and molecular methods (16S rDNA and gyrB). The strain was highly sensitive to 12 kinds of drugs such as ceftriaxone, azithromycin, doxycycline and florfenicol. The medication treatment using florfenicol with three different methods showed that medicated bath treatment was the most effective and achieved the best results of the WGR of (24.23±0.41)% and SGR of (0.77±0.01) %/d. The study provides the theoretical basis and technical reference for disease prevention and control in sea cucumber culture and its healthy breeding.