Feeding Plasticity of Silver Carp and Bighead Carp in Chinese Lakes Based on Next Generation Sequencing

Understanding the feeding differentiation between silver carp and bighead carp is important for predicting the effects of the two carps on food web structure and ecosystem function in lakes and rivers. However, the results from traditional gut content analysis often biased toward the undigested food items, while the stable isotope approach is too rough in taxonomic resolution (i.e., phytoplankton is usually recognized as one type of food). Gut content analysis using next generation sequencing has been used in this study to study the feeding of silver carp and bighead in eutrophic and mesotrophic lakes, Lakes Taihu and Qiandao. Our results showed that there were about 784 species of food items that have been identified totally in gut contents of silver carp and bighead, which is much higher than any results before that uses traditional microscopic examination. 51 species were only found in the gut contents of silver carp and 47 species only in bighead carp in Lake Qiandao, and 49 species were only found in gut contents of bighead and 133 species only in gut of silver carp in Lake Taihu.