DNA条形码在马鞍列岛海域皮氏叫姑鱼胃含物鉴定中的应用

采用分子生物学手段与传统观测手段相结合的方法,对2014年夏季在马鞍列岛海域捕获的201尾皮氏叫姑鱼进行了胃含物分析。解剖后发现其空胃率较高,传统的观测方法仅获得口虾蛄、日本鼓虾、沙蚕、日本蟳幼体4种胃含物,所获得的胃含物中存在大量不可辨认的虾类、蟹类。针对不可辨认的食物糜提取组织DNA,选用线粒体基因细胞色素C氧化酶亚基Ⅰ(mitochondrial cytochrome oxidase subunitⅠ,COⅠ)作为分子标记,在Gen Bank中进行比对分析,并利用MEGA 6.0构建NJ系统进化树,结果鉴定出中华管鞭虾、鲜明鼓虾、巨指长臂虾、日本鼓虾、中国毛虾、褐菖鲉、日本鳀等10种胃含物种类,实验中所获得的基因序列在Gen Bank中的相似度达到97%以上。通过对不可辨认糜的鉴定,在较大程度上解决了对食物团中不可辨认成分鉴定的困惑;同时,发现了新的摄食对象,了解到更加多样的皮氏叫姑鱼的摄食种类信息。因此,DNA条形码技术在不可辨认饵料生物鉴定中的应用价值应得到重视。

Application of DNA barcoding in analyzing food composition of Belanger's croaker (Johnius belangerii) in Ma'an Archipelago

Belanger''s croaker (Johnius belangerii) is a fundamental fish species of family Sciaenidae which usually has high gastric vacuous rate during 24 hours trawl surveys making the diet analysis difficult to continue. However, it plays an important role in the predator-prey relationship in the food web of Ma''an Archipelago, East China Sea. In this study, we use visual inspection with DNA barcoding technology combined previous collected data to make more comprehensive analysis towards its diet compositions and realistic prey-predator relationships. We amplified mitochondrial cytochrome oxidase subunit I (COI) using fish and invertebrates universal primers in sampled fish stomach contents which could not be identified by morphological observation. Our results indicated that using DNA barcoding could successfully identify those partially digested food compositions species, such as Solenocera crassicornis, Alpheus distinguendus, Palaemon macrodactylus, Alpheus japonicus, Acetes chinensis, Sebastiscus marmoratus. We found belanger''s croaker mostly feeds on shrimps (frequency of occurrence, 45%) and crabs (23%), some juvenile fishes (27%) occasionally and among them S. crassicornis, P. macrodactylus, Portunus sanguinolentus, Oratosquilla oratoria had not been observed in summer investigation ever before. In conclusion, the accurate and sufficient diet analysis is the precondition of feeding habit research which could contribute to reasonable suggestions of the management of island reef area ecosystem and fisheries forecasting.