The effect of ileal bypass on sterol balance and plasma cholesterol in the White Carneau pigeon.

The effect of ileal bypass on steady-state sterol balance and plasma cholesterol was studied in sham operated (SO) and ileal bypass (IB) White Carneau pigeons 6 months (Group I) and 18 months (Group II) after surgery while fed their usual cholesterol-free diet. Unlike what has been noted in other animals, the bile acid (BA) and neutral sterol (NS) excretion (mg/kg per day) in IB was not statistically different from that in SO. Group I: BA, 40.2 (SO) vs 39.0 (IB); NS, 13.3 (SO) vs 17.3 (IB). Group II: BA, 55.7 (SO) vs 54.1 (IB); NS, 9.57 (SO) vs 8.84 (IB). IB pigeons had only slightly lower plasma cholesterol levels (postoperative) than SO pigeons. Group I, 329 (SO) vs 271 (IB) mg/dl (P less than 0.05); Group II, 374 (SO) vs 312 (IB) mg/dl. This study indicates that the response to ileal bypass by White Carneau pigeons in terms of cholesterol excretion and plasma cholesterol changes is different than what has been observed in other species.