Abstract: The influence of synbiotics on the predominant bacteria community in the cecal content of broilers was evaluated. Four hundred and fifty oneyearold broilers were randomly divided into five treatments of basic diets and basic diets supplemented with antibiotics, probiotics, prebioticts, synbioticts, respectively. On day 21 and 42, two chickens of each replicate were randomly selected and killed, the cecal contents were sterilely collected, and total cellular DNA from the cecal digesta were extracted and purified for PCRDGGE, then diversity of microbiota was analyzed after DGGE. The results showed the chickens fed with synbiotics showed a higher bacterial diversity and more DGGE bands compared with other treatments on day 21 and 42. The specificity bands of cecal were from uncultured Bacteroidales, uncultured Prevotellaceae, uncultured Clostridiales and plenty of uncultured bacterial without classification．

Key words: synbiotics, DGGE, intestinal microbiota, broiler, cecal