Abundance and Diversity of Several Bacterial Genera in the Mariculture Environment

Although there have been some studies on pathogenic bacteria and their pathogenicity in animals, few studies have assessed the effects of aquaculture on the diversity of potentially pathogenic bacteria. This study used Illumina sequencing and quantitative PCR to explore the diversity of several bacterial genera containing pathogenic bacteria in the mariculture environment and the intestines of different cultured animals. These bacterial genera can be divided into two categories: The first category (14 genera) had high abundances and a low coefficient of variation among similar samples were significantly correlated with the total number of bacteria (r(2) > 0.7, p approximate to 0). The other category (7 genera) with low abundances and a high coefficient of variation had no significant relationship with bacterial abundance. These results indicated that these bacterial genera had different responses and adaptation mechanisms to the aquaculture environment. Principal component analysis (PCA) showed that a high abundance of genera was closely related to the pond environment. The abundance of these bacterial genera in the animals' intestines was much higher than source water, especially for Mycoplasma, Pseudoalteromonas, Vibrio, and Enterococcus, suggesting the aquaculture promoted the high abundance of these bacteria. This study provides a theoretical basis for sediment-associated pathogens acting as a potential pathogen source in the aquaculture environment. This study provides a strategy for disease prevention and control according to the characteristics of potential pathogens in the cultural process.