摘要

Enterococcus durans 6-24 and Bacillus subtilis B9 were isolated from the intestine of shrimp through antibacterial tests, adhesion tests and specific hydrolase activity determinations, in combination with 16S rDNA and physiological and biochemical identification. A preliminary study was carried out on the probiotic effects of 6-24 and B9 in feeding Macrobrachium rosenbergii. After the two strains were added to the feed at 1×107 cfu/kg, a 4-weekfeeding experiment started, and the changes in total blood cells, prophenoloxidase system (proPO), antioxidant system and lysozyme of M. rosenbergii were determined. The research results showed that after M. Rosenbergii was fed with the feed containing 6-24 and B9, the total hymphocyte count increased significantly (p< 0.05), with the activities of phenoloxidase, superoxide dismutase and lysozyme increased simultaneously (phenol oxidase increased by 48.24%; lysozyme increased by 198.00%). The experiments on the intestinal digestive enzymes of Macrobrachium rosenbergii revealed that compared to the control, the activities of digestive enzymes (amylase, protease, lipase) of the experimental group fed with mixed probiotics increased significantly (p< 0.05) (among which, the protease increased by 84.80%). Finally, the research revealed that the number of cultivable Vibrio in the intestine of Macrobrachium rosenbergii fedwith6-24 and B9 decreased by 59.76% (p< 0.05). The results showed that Enterococcus durans 6-24 and Bacillus subtilis B9 can improve the intestine environment and immunity level of M. rosenbergii, and have the potential to become probiotic shrimp feed additives.