Ammonia production from uric acid and its absorption from the caecum of the cockerel.

1. Experiments were done in vitro and in situ in the caeca to measure ammonia production from uric acid and its absorption. 2. When uric acid was introduced into a caecal sac containing mixed caecal micro-organisms 0.77 disappeared in 1 h, with the concomitant appearance of ammonia. 3. Amounts of ammonia produced from added [15N] uric acid in the caeca in situ after 30 min and in caecal medium in vitro after 10 h, were 0.28 and 0.25 respectively of the added 15N. 4. About 0.92 of the ammonia introduced into a caecal sac disappeared from the lumen fluid in 30 min. 5. It is concluded that ammonia is produced from uric acid by caecal micro-organisms and rapidly absorbed.