A bile acid analogue, SEHCAT (tauro-23-75SE-selena-homocholic acid), was used to determine bile acid pool size, turnover time, and distribution in the developing broiler chick. Bile acid pool size was significantly affected by age and followed a quintic trend (a fifth degree polynomial). It remained steady until 30 days of age when it decreased significantly and then rose significantly at 37 days of age. The bile acid pool half-life remained constant until 28 days of age when it increased significantly and then held steady until it increased again at 8 wk of age following a quartic trend. The distribution of bile acids was affected by age with the amount in the gizzard, duodenum, cloaca, liver, and gall bladder varying significantly with age. Jejunal, ileal, and cecal bile acids did not vary significantly with age. Liver bile acid levels followed a quintic trend, rising until 23 days of age and dropping sharply at 30 days of age and holding steady.