ISSN: 2577-4050
Authors: Yuexin Ma*, Yanyu Li, Chen Jiang, Tao Zhang and Wei Tao
In order to select the potential prbiotics for the culture of the pufferfish Takifugu rubripes, 30 bacterial strains were isolated from the intestine of juvenile pufferfish. Four strains were screened based on the isolates producing a variety of enzymes (protease, amylase and lipase) and/or having antagonistic activity against the pathogen Vibro harveyi. Hemolysis was tested in four strains and the results showed that F15 did not secrete hemolysin, without potential pathogenicity. F15 was proven to be safe for young pufferfish challenged by intraperitoneal injection. It was identified as Pseudoalteromonas sp. by 16S rRNA gene sequencing. Young pufferfish were assigned to three groups (three tanks per group) and received the control diet (basal diet) and diets supplemented with F15 at 107 and 109 cells g-1. After 14 days of feeding, all pufferfish fed the F15-supplemented diets had a significant enhanced intestinal and hepatopancreas pepsin, trypsin, lipase and amylase activities as compared with the controls. Moreover, the intestinal pepsin and amylase activities and the hepatopancreas four digestive enzymes activities of pufferfish fed the 109 cells g-1 F15 diet were significantly higher than those of pufferfish fed the 107 cells g-1 F15 diet. It can be concluded that Pseudoalteromonas sp.15 can improve intestinal and hepatopancreas digestive enzyme activity of young pufferfish.
Keywords: Takifugu rubripes; Probiotics; Selection; Pseudoalteromonas sp.; Digestive Enzyme Activity
