Evaluation of the effect of indigenous probiotic administration on gut bacterial diversity of Pacific white shrimp Penaeus vannamei

Abstract

The objective of this study was to assess the impact of a native probiotic product on the intestinal bacteria biodiversity of Penaeus vannamei. Shrimp larvae were administered the probiotic via food (treatment 1), through culture water (treatment 2), and a control group received no probiotics (treatment 3). After three months of rearing, bacteria were isolated from the shrimp intestines, and initial identification was conducted based on morphological, biochemical, and physiological traits. The diversity of intestinal bacterial flora was assessed using PCR-RFLP methods, focusing on the determination of 16S rRNA gene sequences. Results revealed a significantly higher abundance of cultivable bacteria in the intestines of shrimp from treatment 1 (2.4 x 107 CFU/gr) compared to those receiving probiotics through water (6.16 x 106 CFU/gr). The probiotic product led to a reduction in bacterial diversity in the intestines of treated shrimp, decreasing from 10 to 6 genera. Additionally, the frequency of Vibrio bacteria decreased by 20%, while other opportunistic pathogenic bacteria such as Pseudomonas, Aeromonas, Shewanella, and Photobacterium were eliminated. Overall, the findings suggest that administering probiotics through food was more effective in modulating the diversity of the shrimp intestinal microbiome. This study enhances our understanding of the impact of indigenous probiotics on the composition and dynamics of the intestinal microbiome of P. vannamei.

Keywords

• gut microbiome
• probiotic
• pacific white shrimp
• bacteria genetic identification