HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Misciattelli, L. Articles by Hvelplund, T. Search for Related Content PubMed PubMed Citation Articles by Misciattelli, L. Articles by Hvelplund, T.

Milk Production, Nutrient Utilization, and Endocrine Responses to Increased Postruminal Lysine and Methionine Supply in Dairy Cows

Danish Institute of Agricultural Sciences Department of Animal Nutrition and Physiology P.O. Box 50, DK-8830 Tjele, Denmark

Corresponding author:
T. Hvelplund; e-mail:
torben.hvelplund{at}agrsci.dk.

The effect of increased postruminal supply of lysine and methionine was investigated in a production trial involving 64 dairy cows in early lactation. Within each of two basal rations, based on either corn silage or grass silage, rations were either naturally deficient in lysine or fortified with 24 g of lysine in a rumen-protected form and naturally deficient in methionine or fortified with 12 g of methionine in a rumen-protected form. The data were analyzed separately for the four lysine and the four methionine treatment groups. Milk production, body weight gain, and plasma concentrations of insulin-like growth factor-I, bovine somatotropin, insulin, glucose, nonesterified fatty acids, and urea were monitored over a 12-wk period. Supplementation with protected methionine led to increases in milk fat and protein contents of 2.4 and 1.8 g/kg of milk, respectively. Supplementation with protected lysine or methionine numerically increased protein yield comparable to values reported in the literature, but the treatment effects were not statistically significant. Efficiency of utilization of absorbed amino acids for milk protein synthesis and efficiency of utilization of metabolizable energy for milk production were not significantly altered in response to increased postruminal lysine and methionine flow, but a numerically increased efficiency of utilization of total amino acids was observed. No significant effect of lysine or methionine supplementation was observed on endocrine parameters nor on plasma metabolite concentrations. However, across treatment groups, high milk yield was correlated with low plasma insulin-like growth factor-I concentrations (r = -0.44) and partially with low plasma nonesterified fatty acids concentration and insulin levels (r = -0.26), while body weight gain was negatively correlated (r = -0.33) with elevated plasma bovine somatotropin concentrations.

Key Words: protein utilization • insulin-like growth factor-I • bovine somatotropin • insulin

Abbreviation key: AAT = AA absorbed in the intestine, AAT-Lys = lysine absorbed in the intestine, AAT-Lys% = percent lysine in intestinally absorbed AA, AAT-Met = methionine absorbed in the intestine, AAT-Met% = percent methionine in intestinally absorbed AA, DCHO = digestible carbohydrates, DCF = digestible crude fat, ECM = energy corrected milk, EPD = effective protein degradability, HLG = high lysine, grass silage based, HLM = high lysine, corn silage based, HMG = high methionine, grass silage based, HMM = high methionine, corn silage based, k_AAT = efficiency of utilization of AAT for milk protein synthesis, k_l = efficiency of utilization of ME for milk synthesis, LLG = low lysine, grass silage based, LLM = low lysine, corn silage based, LMG = low methionine, grass silage-based, LMM = low methionine, corn silage-based, ME = metabolizable energy, PBV = protein balance in the rumen, RHCHO = rapidly hydrolyzable carbohydrates

This article has been cited by other articles:

				J. Cho, T. R. Overton, C. G. Schwab, and L. W. Tauer Determining the Amount of Rumen-Protected Methionine Supplement That Corresponds to the Optimal Levels of Methionine in Metabolizable Protein for Maximizing Milk Protein Production and Profit on Dairy Farms J Dairy Sci, October 1, 2007; 90(10): 4908 - 4916. [Abstract] [Full Text] [PDF]

				C. D. Wildman, J. W. West, and J. K. Bernard Effect of Dietary Cation-Anion Difference and Dietary Crude Protein on Performance of Lactating Dairy Cows During Hot Weather J Dairy Sci, April 1, 2007; 90(4): 1842 - 1850. [Abstract] [Full Text] [PDF]

				L. C. Zahra, T. F. Duffield, K. E. Leslie, T. R. Overton, D. Putnam, and S. J. LeBlanc Effects of Rumen-Protected Choline and Monensin on Milk Production and Metabolism of Periparturient Dairy Cows J Dairy Sci, December 1, 2006; 89(12): 4808 - 4818. [Abstract] [Full Text] [PDF]

				M. Roesch, M. G. Doherr, and J. W. Blum Performance of Dairy Cows on Swiss Farms with Organic and Integrated Production J Dairy Sci, July 1, 2005; 88(7): 2462 - 2475. [Abstract] [Full Text] [PDF]

				C. L. Girard, H. Lapierre, J. J. Matte, and G. E. Lobley Effects of Dietary Supplements of Folic Acid and Rumen-Protected Methionine on Lactational Performance and Folate Metabolism of Dairy Cows J Dairy Sci, February 1, 2005; 88(2): 660 - 670. [Abstract] [Full Text] [PDF]