摘要

Probiotic bacteria are applied to prevent and control infection by disease-causing agents. This study evaluated the potential benefits of dietary applied Aeromonas sobria strain GC2 and a commercial product, BioPlus 2B (TM) (B2B), as probiotic agents for barramundi (Lates calcarifer). GC2 or B2B were added to feed at 10(8) CFU/g feed and 5 mg/g feed, respectively, and fish were fed the experimental diets for 14 or 28 days. The GC2-supplemented diet resulted in significant alteration of the gut bacterial community, with the new community remaining stable throughout the sampling period, but did not significantly affect the measured immune parameters. When compared with the control and GC2 groups, the B2B-supplemented diet did not significantly alter the intestinal bacterial community of the fish, but resulted in significantly (p < 0.05) higher head-kidney leukocyte pinocytotic activity. At the end of the experimental feeding (14 or 28 days), fish were challenged with the pathogen Streptococcus iniae by intra-peritoneal injection. The probionts did not affect the fishes' resistance to infection, which resulted in very high mortality (above 90%) in all treatment groups.

  • 出版日期2011