2Faculty of Veterinary Science (B19), University of Sydney, NSW206, Australia.
Animal Nutrition Group, National Dairy Development Board, Anand388 001 (Gujarat) India
1Corresponding author. Tel.: +91-2692-226248, Fax: +91-2692-260158. E-mail address: mrgarg@nddb.coop
Protein meals (1-mm particle size) were used to determine the rumen undegradable protein (UDP) by in vitro ammonia release (IVAR) and by near-infrared spectroscopy (FOSS NIR System, 1100 – 2500 nm) methods. UDP values in various formaldehyde treated and untreated protein meals, estimated by NIR were compared with that of traditional IVAR method and was found to be highly correlated (r=0.67 to r=92; p<0.01). Partial least square analysis (PLS) model was used to develop the calibration equations with F values of >10, indicating acceptance of these calibration equations for predicting the UDP values. Regression coefficients were used to develop the mathematical relationship for UDP values, between the NIR spectra and IVAR methods. Based on the values obtained by IVAR and NIR methods, various regression equations have been developed, for various treated and untreated protein meals.
Protein meals, Rumen undegradable protein, Near Infrared spectroscopy, In vitro ammonia release method
