In order to find out the normal bacterial flora in the gastrointestinal tract of channel catfish (Ictalurus punctatus Rafinsque), aerobic and facultative anaerobic bacteria were quantitatively analyzed using the spread-plate method, and the separate strains were classified. The results showed that the number of bacteria in foregut, midgut and posterior intestine of channel catfish were 3.72×106cfu/g,4.32×106cfu/g and 16.25×106 cfu/g respectively. The main bacterial flora in foregut were alcaligenes,...