Study on effects of extracted probiotics from microbial flora of digestiveudsystem on growth indices in beluga (Huso huso) and Persian sturgeon (Acipenser persicus)

摘要

Isolation of Lactic Acid Bacteria (LAB) was carried out from gastro intestinaludtract of beluga and Persian sturgeon at international sturgeon research instituteudand PCR has been used for bacteria Identification.udTwo species of LAB including Enterococcus seriolicida and Leuconostocudmesenteroides were isolated from Gastrointestinal tract (GI) of persian sturgeonudin this study and the counts of Leu. mesenteroides (4.63×102 CFU/gr of GI)udwas significantly higher than other species. Lactobacillus curvatus,udLactococcus raffinolactis, Lactococcus lactis and Streptococcus sp. were alsoudisolated from GI of beluga and maximum counts was belonged to Lb. curvatusud(4.63×102 CFU/gr of GI) in this species. Dominant species were lyophilizedudand adding to the water since start of mix feeding of sturgeon with differentudcounts including 2×109, 5×109 and 9×109 CFU/gr of live food, 4 times a day.udThe results revealed that the maximum and minimum growth rate and protease,udamylase, and lipase activity in beluga was gained by using of Lb. curvatus withudtotal viable count of 9×10 9 CFU/gr of live food and Leu. mesenteroides withudtotal viable count of 9×109 CFU/gr of live food.udAccording to the results of this study, the maximum and minimum growth rateudand protease, amylase, and lipase activity in Persian sturgeon was gained byudusing of Leu. mesenteroides with total viable count of 2×10 9 CFU/gr of liveudfood and Lb. curvatus with total viable count of 9×109 CFU/gr of live food.udHistological study showed that gastrointestinal development was same duringudlarva rearing in control and other treatments but the size of liver was bigger inudtreatments that received nonspecific LAB in both species.udAccording to the results, positive effects of using dominant specific LABudbacteria for larviculture of sturgeon has been proved in this study.