Association of Fungi in the Intestine of Black Carp and Grass Carp Compared with their Cultured Water

Abstract

The current study aimed to explore the intestinal fungal community characteristics of grass carp and black carp and their correlation with cultured water fungi. Grass carp, black carp, and their cultured water samples were collected from the same reservoir. Based on the Illumina HiSeq 2500 high-throughput sequencing platform, the fungal internal transcribed spacer (ITS) region sequences of each sample were determined and analyzed. The results showed that a total of 1,193,261 valid sequences with an average length of 235–251 bp were detected in the three groups of samples, which included 9 phyla, 27 classes, 65 orders, and 288 genera. Ascomycota, Basidiomycota, Mortierellomycota, and Chytridiomycota were the dominant phyla. Mortierella, Thermoascus, and Thermomyces were the main genera. Compared with cultured water samples, the abundance of major phyla and genera was significantly different from grass carp and black carp samples, but there was no significant difference between grass carp and black carp samples. Surprisingly, Ascomycota was enriched in CY and QY samples. In conclusion, the dominant fungi in grass carp, black carp, and cultured water samples were similar, but the relative abundance was significantly different compared with cultured water samples. The results will provide a basis for the tolerance of fish with different feeding habits to colonize water and provide a theoretical basis for the regulation and improvement of aquaculture water quality and the realization of healthy and green aquaculture of fish.