Shrimp farming, a significant contributor to global aquaculture, faces substantial challenges due to diseases caused by pathogens like Vibrio species. Antibiotic use, once common, is now restricted due to environmental and health concerns. This study aims to evaluate alternative strategies, particularly focusing on the influence of feeding regimens and additives on Vibrio spp. in the gut of Pacific white shrimp (Litopenaeus vannamei ).
In the first part of this study , various feeding regimens (single feeding, four feedings per day, and continuous feeding) were tested to assess their effec t on Vibrio counts on TCBS plates in both shrimp gut and feces collected . Sixty shrimp were randomly selected and allocated to three tanks (HI, H2, and H3 ), each containing 150 litre s of culture water, and were fed over a five-day period. Examination of both gut and feces samples indicated that continuous feeding resulted in the lowest Vibrio spp. count, indicating a reduction in bacterial growth, whereas feeding once daily had the least influence on the bacteria population. The experimental results are depicted in Figure 1. This finding highlights the potential influence of feeding frequency on gut bacteria dynamics in shrimp aquaculture.
The subsequent experiment examined the inhibitory effects of a feed additive containing a blend of short-chain fatty acids, carpic carpylic, butyric and lauric acid on Vibrio growth. The shrimp were fed a reference diet or reference diet supplemented with 0.4% fatty acid blend for five days. Analysis of bacteria inside the gut and feces samples revealed that the addition of fatty acid s in the feed resulted in significantly lower Vibrio counts on TCBS plates, measuring only 1.39 x 105 and 7.30 x 105 (CFU.ml-1) in the gut and feces respectively, compared to 2.23 x 105 and 1.13 x 10 6 isolated from gut and feces samples of shrimp fed the reference diet only (see Figure 2). Understanding the relationships between bacterial count influenced by the given diet is crucial for developing sustainable disease management practices in shrimp farming.
Keywords : Pacific white shrimp, Vibrio spp., feeding regimens, additives, aquaculture sustainability