Journal of Animal Science, Vol 73, Issue 5 1459-1465, Copyright © 1995 by American Society of Animal Science

JOURNAL ARTICLE

A three-step in vitro procedure for estimating intestinal digestion of protein in ruminants

S. Calsamiglia and M. D. Stern
Department of Animal Science, University of Minnesota, St. Paul 55108, USA.

A three-step in vitro procedure was developed to estimate intestinal digestion of proteins in ruminants. Dacron bags containing feed samples were suspended in the rumen for 16 h. Residue containing 15 mg of N after ruminal exposure was incubated for 1 h in 10 mL of a .1 N HCl solution containing 1 g/L of pepsin. After incubation, pH was neutralized with .5 mL of 1 N NaOH and 13.5 mL of a pH 7.8 phosphate buffer containing 37.5 mg of pancreatin were added to the solution and incubated at 38 degrees C. After a 24-h incubation, 3 mL of a 100% (wt/vol) trichloroacetic acid solution were added to precipitate undigested proteins. Preincubation of samples in the rumen did not affect (P > .05) pepsin-pancreatin digestion of residual CP in soybean meal (SBM), corn gluten meal (CGM), and blood meal (BM) and reduced (P < .05) pepsin-pancreatin digestion of residual CP in hydrolyzed feather meal (HFM), fish meal (FM), and meat and bone meal (MBM) (80 vs 70, 88 vs 81, and 82 vs 56%, respectively, for nonruminal vs ruminal preincubation). Pepsin digestion before pancreatin digestion increased (P < .05) CP digestion of all proteins tested by a mean of 23 percentage units. The pancreatin digestion step was validated using 34 duodenal samples from which small intestinal CP digestion was determined in vivo. The regression equation of in vivo estimates on pancreatin digestion had an r value of .91 (P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)

This article has been cited by other articles:

				S. E. Boucher, S. Calsamiglia, C. M. Parsons, H. H. Stein, M. D. Stern, P. S. Erickson, P. L. Utterback, and C. G. Schwab Intestinal digestibility of amino acids in rumen-undegraded protein estimated using a precision-fed cecectomized rooster bioassay: II. Distillers dried grains with solubles and fish meal J Dairy Sci, December 1, 2009; 92(12): 6056 - 6067. [Abstract] [Full Text] [PDF]

				S. E. Boucher, S. Calsamiglia, C. M. Parsons, H. H. Stein, M. D. Stern, P. S. Erickson, P. L. Utterback, and C. G. Schwab Intestinal digestibility of amino acids in rumen undegradable protein estimated using a precision-fed cecectomized rooster bioassay: I. Soybean meal and SoyPlus J Dairy Sci, September 1, 2009; 92(9): 4489 - 4498. [Abstract] [Full Text] [PDF]

				Z. J. Cao, J. L. Anderson, and K. F. Kalscheur Ruminal degradation and intestinal digestibility of dried or wet distillers grains with increasing concentrations of condensed distillers solubles J Anim Sci, September 1, 2009; 87(9): 3013 - 3019. [Abstract] [Full Text] [PDF]

				S. E. Boucher, S. Calsamiglia, C. M. Parsons, M. D. Stern, M. Ruiz Moreno, M. Vazquez-Anon, and C. G. Schwab In vitro digestibility of individual amino acids in rumen-undegraded protein: The modified three-step procedure and the immobilized digestive enzyme assay J Dairy Sci, August 1, 2009; 92(8): 3939 - 3950. [Abstract] [Full Text] [PDF]

				K. Doiron, P. Yu, J. J. McKinnon, and D. A. Christensen Heat-induced protein structure and subfractions in relation to protein degradation kinetics and intestinal availability in dairy cattle J Dairy Sci, July 1, 2009; 92(7): 3319 - 3330. [Abstract] [Full Text] [PDF]

				M. S. Awawdeh, E. C. Titgemeyer, J. S. Drouillard, R. S. Beyer, and J. E. Shirley Ruminal Degradability and Lysine Bioavailability of Soybean Meals and Effects on Performance of Dairy Cows J Dairy Sci, October 1, 2007; 90(10): 4740 - 4753. [Abstract] [Full Text] [PDF]

				D. H. Kleinschmit, J. L. Anderson, D. J. Schingoethe, K. F. Kalscheur, and A. R. Hippen Ruminal and Intestinal Degradability of Distillers Grains plus Solubles Varies by Source J Dairy Sci, June 1, 2007; 90(6): 2909 - 2918. [Abstract] [Full Text] [PDF]

				S. I. Borucki Castro, L. E. Phillip, H. Lapierre, P. W. Jardon, and R. Berthiaume Ruminal Degradability and Intestinal Digestibility of Protein and Amino Acids in Treated Soybean Meal Products J Dairy Sci, February 1, 2007; 90(2): 810 - 822. [Abstract] [Full Text] [PDF]

				C. Lanzas, L. O. Tedeschi, S. Seo, and D. G. Fox Evaluation of Protein Fractionation Systems Used in Formulating Rations for Dairy Cattle J Dairy Sci, January 1, 2007; 90(1): 507 - 521. [Abstract] [Full Text] [PDF]

				E. Tabacco, G. Borreani, G. M. Crovetto, G. Galassi, D. Colombo, and L. Cavallarin Effect of Chestnut Tannin on Fermentation Quality, Proteolysis, and Protein Rumen Degradability of Alfalfa Silage J Dairy Sci, December 1, 2006; 89(12): 4736 - 4746. [Abstract] [Full Text] [PDF]

				S. Gargallo, S. Calsamiglia, and A. Ferret Technical note: A modified three-step in vitro procedure to determine intestinal digestion of proteins J Anim Sci, August 1, 2006; 84(8): 2163 - 2167. [Abstract] [Full Text] [PDF]

				M. T. Socha, D. E. Putnam, B. D. Garthwaite, N. L. Whitehouse, N. A. Kierstead, C. G. Schwab, G. A. Ducharme, and J. C. Robert Improving Intestinal Amino Acid Supply of Pre- and Postpartum Dairy Cows with Rumen-Protected Methionine and Lysine J Dairy Sci, March 1, 2005; 88(3): 1113 - 1126. [Abstract] [Full Text] [PDF]

				C. G. Schwab, T. P. Tylutki, R. S. Ordway, C. Sheaffer, and M. D. Stern Characterization of Proteins in Feeds J Dairy Sci, July 1, 2003; 86(13_suppl): E88 - 103. [Abstract] [Full Text] [PDF]

				S. Noftsger and N. R. St-Pierre Supplementation of Methionine and Selection of Highly Digestible Rumen Undegradable Protein to Improve Nitrogen Efficiency for Milk Production J Dairy Sci, March 1, 2003; 86(3): 958 - 969. [Abstract] [Full Text] [PDF]