Intestinal disappearance and mesenteric and portal appearance of amino acids in dairy cows fed ruminally protected methionine.

摘要: An experiment was conducted to compare the rates of disappearance amino acids (AA) from small intestine and their net appearance in blood draining only (mesenteric-drained viscera) whole gastrointestinal tract (portal-drained cows fed a silage-based diet supplemented or not with ruminally protected Met. Five lactating dairy (118+/-4 DIM) equipped duodenal ileal cannulae (n = 2) cannula 3), two which were multicatheterized, TMR top dressed 0 72 g Met per day. The addition increased flux leading higher apparent digestibility intestine. Sixty-six percent bypassed rumen 82% that disappeared Arterial plasma concentrations numerically (45 vs. 18 microM), while total AA concentration decreased. Feeding resulted urea-N glucose arterial plasma. Milk production milk composition unaffected. essential across equivalent (101%) through mesenteric-drained viscera portal:mesenteric-drained ratio for each varied 38% Thr 76% Phe. 66%. These results confirm observations made pigs sheep.