Microflora in fish digestive tract plays significant role in digestion and metabolism

Microflora of the environment plays an important role in the formation of the microflora of the digestive tract of fishes (Strom and Olafsen Microbiology of poecilotherms Elsevier, Amsterdam, pp 181-185 1990; Hansen et al. Appl Environ Microbiol 58:461-470 1992). Compared to water, digestive tract is an ecosystem far richer in nutrients and therefore more favorable for the growth of the majority of bacteria. Definitely, not all bacteria in food which gain entry in the digestive tract of fishes establish themselves there (Yan-Bo Wang et al. Aquaculture 281(1-4): 1-4 2008). Part of them adapts themselves in the digestive tract, whereas the others are digested by the enzymes produced by the host organism. Microorganisms present in the digestive tract feed on the food of the host organism which is digested by the enzymes produced by them and by the latter. 'Chymous' gets formed which decides the abundance and qualitative composition of microorganisms present in digestive tract.