Short Communication: A Novel System to Estimate Protein Degradability in Legume and Grass Hays

¹ Department of Dairy Science, University of Wisconsin-Madison 53706

Previous research from our laboratory has demonstrated that near-infrared reflectance spectroscopy has utility in predicting rumen-undegradable protein (RUP) contents of legume and grass silages. This study was conducted to evaluate whether application of previous research techniques could yield a useful near-infrared reflectance spectroscopy RUP prediction system for legume and grass hays. Legume and grass hays (n = 106) were evaluated for RUP content by in situ techniques in four ruminally cannulated cows. In situ RUP for legume and grass hays averaged 25.9% CP and ranged from 14.6 to 45.5% CP, respectively. We developed a near-infrared reflectance spectroscopy RUP calibration equation for the legume and grass hay data set using in situ RUP contents as base data. This procedure resulted in an acceptable (R² = 0.87, SE = 2.46% CP) near-infrared reflectance spectroscopy equation to predict RUP content of legume and grass hays. Data suggest that near-infrared spectroscopy predicts RUP contents of legume and grass hays with accuracies similar to legume and grass silages.

Key Words: hay • near-infrared • protein degradation

Submitted on October 12, 1999
Accepted on February 4, 2000

This article has been cited by other articles:

				R. L. Mentink, P. C. Hoffman, and L. M. Bauman Utility of near-infrared reflectance spectroscopy to predict nutrient composition and in vitro digestibility of total mixed rations. J Dairy Sci, June 1, 2006; 89(6): 2320 - 2326. [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]