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Partition of portal-drained visceral net flux in beef steers

2. Net flux of volatile fatty acids, D-β-hydroxybutyrate and L-lactate across stomach and post-stomach tissues*

Published online by Cambridge University Press:  09 March 2007

Christopher K. Reynolds
Affiliation:
U.S. Department of Agriculture, Agricultural Research Service, Ruminant Nutrition Laboratory, Building 162, BARC-East, Beltsville, MD 20705, USA and University of Maryland, College Park, MD 20742, USA
Gerald B. Huntington
Affiliation:
U.S. Department of Agriculture, Agricultural Research Service, Ruminant Nutrition Laboratory, Building 162, BARC-East, Beltsville, MD 20705, USA and University of Maryland, College Park, MD 20742, USA
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Abstract

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1. Net flux of volatile fatty acids (VFA), D-β-hyroxybutyrate (BOHB) and L-lactate across post-stomach (anterior mesenteric-drained viscera (MDV)), stomach and total hepatic portal-drained viscera (PDV) tissues was measured in two beef steers (mean live weight 390 kg).

2. Net flux was measured while steers were fed, in sequence, on (1) chopped lucerne (Medicato sativa) (twelve meals/d), (2) chopped lucerne (two meals/d) and (3) a pelleted concentrate diet containing 780 g ground maize/ kg (two meals/d).

3. Five hourly net flux measurements were obtained on 2 d for each dietary regimen, beginning 0.5 h before a meal delivered at 08.00 hours. Net flux was calculated as venous-arterial concentration differences (VA) multiplied by blood flow (measured by downstream dilution of p-aminohippurate (PAH)).

4. Stomach tissues accounted for 85 to over 100% of net VFA and BOHB appearance across PDV. Net appearance across stomach tissues represented 74% of net PDV L-lactate appearance.

5. When lucerne was given, there was net utilization of arterial acetate and BOHB across MDV. This MDV utilization may reflect acetate and BOHB use as an energy source or their incorporation into mesenteric fat.

6. When concentrate was given, more n-butyrate and n-valerate and less L-lactate appeared across PDV and less 3-methylbutyrate appeared across stomach tissues than when lucerne was given. Postprandial increases in VFA, BOHB and L-lactate net flux across PDV followed meal-feeding of lucerne.

7. On a net basis, the relative contribution of MDV tissues to total PDV net appearance of VFA and BOHB was small (< 15%) in these steers.

Type
General Nutrition papers
Copyright
Copyright © The Nutrition Society 1988

References

Barcroft, J., McAnally, R. A. & Phillipson, A. T. (1944) Journal of Experimental Biology 20, 120129.CrossRefGoogle Scholar
Bergman, E. N. & Wolff, J. E. (1971) American Journal of Physiology 221, 586592.CrossRefGoogle Scholar
Giesecke, D. & Stangassinger, M. (1980). In Digestive Physiology and Metabolism in Ruminants, pp. 523540. [Ruckebush, Y. and Thivend, P., editors]. Lancaster: MTP Press.CrossRefGoogle Scholar
Huntington, G. B. & Prior, R. L. (1983) Journal of Nutrition 112, 22802288.CrossRefGoogle Scholar
Huntington, G. B., Prior, R. L. & Britton, R. A. (1981) Journal of Nutrition 111, 11641172.CrossRefGoogle Scholar
Huntington, G. B. & Reynolds, P. J. (1983) Journal of Dairy Science 66, 8692.CrossRefGoogle Scholar
Janes, A. N., Weekes, T. E. C. & Armstrong, D. G. (1985) British Journal of Nutrition 54, 449458.CrossRefGoogle Scholar
Katz, M. L. & Bergman, E. N. (1969) American Journal of Physiology 216, 953960.CrossRefGoogle Scholar
Marty, J. & Vernay, M. (1984) British Journal of Nutrition 51, 265277.CrossRefGoogle Scholar
Masson, M. J. & Phillipson, A. T. (1951) Journal of Physiology 113, 189206.CrossRefGoogle Scholar
Pennington, R. J. (1951) Biochemical Journal 51, 251258.CrossRefGoogle Scholar
Pethick, D. W., Lindsay, D. B., Barker, P. J. & Northrup, A. J. (1981) British Journal of Nutrition 46, 97110.CrossRefGoogle Scholar
Reynolds, C. K. & Huntington, G. B. (1988) British Journal of Nutrition 60, 539551.CrossRefGoogle Scholar
Reynolds, P. J., Huntington, G. B. & Reynolds, C. K. (1986). Journal of Animal Science 63, Abstr.Google Scholar
Schaefer, A. L. & Young, B. A. (1980) Canadian Journal of Animal Science 60, 677681.CrossRefGoogle Scholar
Somogyi, M. (1945) Journal of Biological Chemistry 160, 6973.CrossRefGoogle Scholar
Stevens, C. E. & Stettler, B. K. (1966) American Journal of Physiology 210, 365372.CrossRefGoogle Scholar
Thorlacius, S. O. & Lodge, G. A. (1973) Canadian Journal of Animal Science 53, 279288.CrossRefGoogle Scholar
Wahle, K. W. J., Weekes, T. E. C. & Sherratt, H. S. A. (1972) Comparative Biochemistry and Physiology 41B, 759769.Google Scholar
Weekes, T. E. C. & Webster, A. J. F. (1975) British Journal of Nutrition 33, 345438.Google Scholar
Weigand, E., Young, J. W. & McGilliard, A. D. (1972) Biochemical Journal 126, 201209.CrossRefGoogle Scholar
Williamson, D. H. & Mellanby, J. M. (1974). In Methods of Enzymatic Analysis, 2nd ed, pp. 18371839 [E. N. Bergmeyer, editor]. New York: Academic Press.Google Scholar
Windmueller, H. G. & Spaeth, A. E. (1978) Journal of Biological Chemistry 253, 6976.CrossRefGoogle Scholar