Identifying Bacterial flora of rainbow trout brood stocks (Oncorhynchus mykiss) and its assumed importance from probiotical view

Document Type : Biology(Animal)

Authors

1 Applied-Scientific Higher Education Institute of Jihad-e-Agriculture, P.O.Box: 13145-1783 Tehran, Iran

2 Isfahan Agricultural Jihad Training Complex

Abstract

The aim of present study was to identify the bacteria in the intestinal of rainbow trout’s brood stocks by considering to have the desire effect of probiotic for substitute of antibiotics and stimulating substances for growth and immunity in rainbow trout’s brood stock culture. Positive Gram bacteria with effect for acid lactic production by possibility of been probitic can be important results of this study for culturing and increasing immunity of rainbow trout’s brood stock and improvement reproduction yield and larvae survival. For this reason, 30 brood stocks (15 males and 15 females) in 15°C temperature caught and with adequate airing, transferred to laboratory of Jihad-e-Agriculture Educational Center, Esfahan. Then, fish were biometry and mean weight of 2-year male brood stocks were 1860g, total length 46cm and mean weight of 3-year female brood stocks was 1940g and total length was 49cm. After word, outside of brood stocks body were disinfected by 70% alcohol and after opening body with sterilized equipment and then digestive system especially the gut had been removed. From intestinal containing primary and subtractive bacterial culture including: Culture by Nutrient Broth, Blood agar, Mac Conkey agar, TSA, TSI, MRS,SIM and MR-VP mediums had been done. Also, by using Gram method staining negative Gram and positive Gram bacteria were separated. Then based on biochemical characteristics of bacterial, tests and references including: Red Methyl, Voges proskauer, Barit, Covax, Oxidase test, Catalase, Starch hydrolysis and act. bacterial identified positively. Results showed bacterial flora in intestinal of rainbow trout’s brood stocks were Streptococcus sp., Leuconostoc sp., Carnobacterium sp., Lactobacillus sp., and Aeromonas sp.

Keywords