PCR 분석에 의한 앨퉁이(Maurolicus japonicus) 위내용물의 유전적 종분류

Abstract

Determining the diets of marine vertebrates by gut content analysis is problematic. The consumed organisms become mostly unrecognizable once partly digested, while those with hard remains (e.g. skeletons) may bias the analysis. Here, we adopt a DNA-based method similar to those used for microbial diversity surveys as a novel approach to study the diets of Maurolicus japonicus, a Sternoptichid light fish. Polymerase chain reaction (PCR) amplified a 430bp region of 28S rDNA gene and the amplified DNA was sequenced. Then, species identification was performed by comparison of the sequences with those in GenBank. Morphological examination of the gut contents was also carried out. In total, eight different 28S rDNA sequences were obtained from two gut content specimens. One ofthem matched with the sequence of Metridia pacifica which appeared in the environmental zooplankton samples. But, it was not identified from the same gut content specimen by morphological analysis. This result suggests that not only morphological examination but also genetic identification are necessary to identify species composition of the fish gut contents.