Study on effect feedings with probiotics in increasing resistance to Aeromonas hydrophila and Changes in gut bacterial communities Sander lucioperca

This study evaluated the effect of dietary administration Lactobacillus brevis MF01 on survival rate of total bacteria, lactic acid bacteria intestinal tract fish and changes in gut bacterial communities Sander lucioperca. Lactobacillus brevis was isolated and identified from intestine of Sander luciopercaby biochemical and molecular tests.Fish were fed with dietary administration containing A1 (L.brevis MF01 10 10 CFU / g), A2 (L. brevis MF01 10 8CFU / g) and the control group (without Lactobacillus) for 45 days. At the end of the feeding period, fish were challenged with 4.5× 10 8CFU /ml Aeromonas hydrophila. The intestinal micro biota includes lactic acid bacteria and total bacteria at different times (15,30, 45 days) and 15 days after stopping feedings with probiotics were performed by using MRS agar, Plate count agar media. The lactic acid bacteria levels were significantly increased compared to the control group following probiotics administration in diet (P,< 0.05). The highest number of intestinal micro biota was observed in Lactobacillus brevis 1010Cfu /g treatment (A1)(P < 0.05). Any lactic acid bacteria of the intestine, was not detected in the control group after 15 days. After the end of feeding, the number of total bacteria and Lactic acid bacteria in all groups was decreased. The highest and lowest survival rate, respectively were treatments A1 (86%) and the control group (60%). Discussion and conclusion: The results showed that addition of Lactobacillusbrevis as an additive in feeding of sander lucioperca, significantly increased the lactic acid bacteria, the intestinal bacteria and the survival rate was compared to the control group (injected).