Abstract:
The third stage larvae (L3) of Anisakis typica were detected in 2 species of threadfin bream, Nemipterus hexodon and N. japonicus, from the Gulf of Thailand, and were morphologically and molecularly characterized. Total 100 threadfin breams, 50 Nemipterus hexodon and 50 N. japonicus, were examined with naked eyes after the opening of abdominal cavity with scissors. Almost all infected larvae remained alive and active even the fish were transported for 1-2 days. Anisakid larvae were exclusively distributed in the body cavity and rarely in the liver. The prevalence of A. typica L3 were 68.0% and 60.0% in N. hexodon and N. japonicus and their infection intensities were 3.5 and 4.2 per fish infected each. Morphological and morphometric analysis were performed by viewing specimens under both a light microscope and a scanning electron microscope. Interestingly, the protruded mucron of Anisakis typica under SEM showed a distinct cylindrical shape that differed from the cone shape of A. simplex. The protruded mucron could be used to identify A. typica L3 larvae in the future. A comparison of the ITS1-5.8S-ITS2 rDNA nucleotide sequences of these species revealed high blast scores with A. typica. Conclusively, it was confirmed that A. typica L3 are prevalent in threadfin breams from the Gulf of Thailand, and their morphological and molecular characters are something different from those of other anisakid larvae, including A. simplex and A. pegreffii.
摘要:
在2种鱼鳍中检测到典型的异尖异语的第三阶段幼虫(L3),Nemipterushexodon和N.japonicus,来自泰国湾,并进行了形态和分子表征。总共100条鱼翅,50只Nemipterushexosodon和50只N.japonicus,用剪刀打开腹腔后用肉眼检查。几乎所有受感染的幼虫都保持存活和活跃,甚至鱼也被运输了1-2天。异语幼虫仅分布在体腔中,很少分布在肝脏中。A.typicaL3的患病率分别为68.0%和60.0%。通过在光学显微镜和扫描电子显微镜下观察样品来进行形态和形态测量分析。有趣的是,在SEM下,典型的Anisakis突出的粘蛋白显示出明显的圆柱形,与单纯形的圆锥形不同。突出的粘蛋白将来可用于鉴定A.typaL3幼虫。这些物种的ITS1-5.8S-ITS2rDNA核苷酸序列的比较显示,与典型的A.最后,已经证实,A.typicaL3在泰国湾的鱼鳍中很普遍,它们的形态和分子特征与其他anisakid幼虫不同,包括A.simplex和A.pegreffii。