The effects of ruminal acidosis on volatile fatty acid absorption and plasma activities of pancreatic enzymes in lambs.
Twenty crossbred wethers (41.9 +/- 4.0 kg BW), each fitted with a ruminal cannula and a jugular catheter, were used in a completely randomized design to examine the effects of ruminal acidosis on plasma activities of pancreatic enzymes and fractional rates of VFA absorption. Lambs had ad libitum access to a 50% concentrate diet. Acidosis was induced by an intraruminal dose of glucose at 0, 6, 12, or 18 g/kg BW via the ruminal cannula. Ruminal fluid and plasma were collected 0, 4, 8, 12, 18, 24, 36, 48, and 72 h after dosing. Ruminal fluid pH was reduced (linear, P < .001) with increasing ruminal glucose. Total ruminal VFA concentration decreased (linear, P < .01) and D(-)-lactate (linear, P < .01) and L(+)- lactate (linear, P = .07) concentrations increased with increasing ruminal glucose. Activities of amylase and lipase in plasma were not affected by ruminal glucose (P > .10). Ten days after the acidosis insult, rumens were evacuated and contents were replaced with an isotonic Cr:VFA solution to measure ruminal VFA absorption. Ruminal fluid was collected hourly from 0 to 6 h. Fractional rate of acetate absorption was 13% lower for lambs receiving 18 g/kg BW glucose than for control lambs. In addition, fractional liquid passage rate was lower (P < .05) in lambs receiving 18 g/kg BW glucose 6 mo after the insult of acidosis. These data suggest that a short-term, severe insult of acute acidosis does not result in pancreatic tissue damage but may result in reduced ruminal VFA absorption for an extended period of time.
Krehbiel
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CR
Department of Animal Science, University of Nebraska, Lincoln 68583-0908, USA.
Britton
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RA
Harmon
D L
DL
Wester
T J
TJ
Stock
R A
RA
D000042:Absorption; D000085:Acetates / Q000493:pharmacokinetics; D000138:Acidosis / Q000378:metabolism / Q000503:physiopathology / Q000662:veterinary*; D000681:Amylases / Q000097:blood*; D000818:Animals; D005232:Fatty Acids, Volatile / Q000032:analysis / Q000378:metabolism / Q000493:pharmacokinetics*; D005947:Glucose / Q000009:adverse effects / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D008049:Lipase / Q000097:blood*; D008297:Male; D011897:Random Allocation; D012417:Rumen / Q000737:chemistry / Q000378:metabolism / Q000503:physiopathology*; D012756:Sheep; D012757:Sheep Diseases / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology*; D013997:Time Factors
D000085:Acetates; D005232:Fatty Acids, Volatile; D008049:Lipase; D000681:Amylases; D005947:Glucose