The effects of long term subtherapeutic chlortetracycline (CTC) on intestinal flora,blood ammonia,serum uric acid and performance of broilers were studied.360 Abor Acre male broilers were randomly divided into two groups with 4 replicates.A treatment ration containing 150 mg/kg CTC and a control ration containing no antibiotics were prepared. E.coli,Lactobacillus and Bifidobacterium both in rectum and jejunum were tested every 7 days.Blood ammonia and serum uric acid were analyzed every two weeks.Bod...