1. AOAC. 2000. Association of Official Analytical Chemists. 17th edition. PO Box 54, Washington, DC, USA.
2. Bhat A S, Parmar O S and Gill R S. 2000. Economic impact of challenge feeding on milk yield and its composition in high yielding crossbred cows. Indian Journal of Dairy Science 53(2): 93–98.
3. Bindal Sameer. 2012. ‘Effect of challenge feeding on performance and economics of milk production of crossbred cows’. MVSc. thesis, National Dairy Research Institute, Karnal, Haryana, India.
4. Bwire J M N and Wiktorsson H. 2003. Effect of supplementary feeding strategies on the performance of stall fed dual-purpose dairy cows fed grass hay-based diets. Asian-Australasian Journal of Animal Sciences 16(3): 359–67.
5. Das K S, Das N and Ravikumar G V P P. 2007. Effect of ‘steamingup’ on subsequent production in dairy cows. Indian Journal of Dairy Science 77(7): 583–85.