References
- Agricultural Research Council. 1980. The Nutrient Requirements of Ruminant Livestock. Commonwealth Agricultural Bureaux, Farnham Royal, UK. 121-166.
- Association of Official Agricultural Chemists, and William Horwitz. 2005. Official methods of analysis. Washington, DC: AOAC. 534.
- Barton, B.A., Rosario, H.A., Anderson, G.W., Grindle, B.P. and Carroll, D.J. 1996. Effects of dietary crude protein, breed, parity, and health status on the fertility of dairy cows. Journal of Dairy Science. 79. 2225-2236. https://doi.org/10.3168/jds.S0022-0302(96)76599-2
- Baek, K.S., Yoon, H.S., Lee, W.S., Ahn, H.S., Kim, W.H., Chae, H.S., Kim, N.Y. and Cho, I.C. 2015. Effect of age at the first pregnancy on calving status in holstein heifers. Annals of Animal Resources Sciences. 26. 13-20. https://doi.org/10.12718/AARS.2015.26.1.13
- Blome, R.M., Drackley, J.K., McKeith, F.K., Hutjens, M.F. and McCoy, G.C. 2003. Growth, nutrient utilization, and body composition of dairy calves fed milk replacers containing different amounts of protein. Journal of Animal Science. 81. 1641-1655. https://doi.org/10.2527/2003.8161641x
- Bodine, T.N. and Purvis, H.T. 2003. Effects of supplemental energy and/or degradable intake protein on performance, grazing behavior, intake, digestibility, and fecal and blood indices by beef steers grazed on dormant native tallgrass prairie. Journal of Animal Science. 81. 304-317. https://doi.org/10.2527/2003.811304x
- Broderick, G.A. 2003. Effects of varying dietary protein and energy levels on the production of lactating dairy cows. Journal of Dairy Science. 86. 1370-1381. https://doi.org/10.3168/jds.S0022-0302(03)73721-7
- Brown, E.G., Vandehaar, M.J., Daniels, K.M., Liesman, J.S., Chapin, L.T., Keisler, D.H. and Nielsen, M.S.W. 2005. Effect of increasing energy and protein intake on body growth and carcass composition of heifer calves. Journal of Dairy Science. 88. 585-594. https://doi.org/10.3168/jds.S0022-0302(05)72722-3
- Brugere-Picoux, J. and Brugere, H. 1980. Fat cow syndrome. Recueil de Medecine Veterinaire. 156. 195-200.
- Chalupa, W., O'Dell, G.D., Kutches, A.J. and Lavker, R. 1970. Supplemental corn silage or baled hay for correction of milk fat depressions produced by feeding pellets as the sole forage. Journal of Dairy Science. 53. 208-214. https://doi.org/10.3168/jds.S0022-0302(70)86181-1
- Choi, B.R. 2004. Nutritional supplementing ways on feeding and management of dairy cow. Journal of Veterinary Clinics. Proceedings of the congress Korean society of veterinary clinics. 5-22.
- Collier, R.J., Doelger, S.G., Head, H.H., Thatcher, W.W. and Wilcox, C.J. 1982. Effects of heat stress during pregnancy on maternal hormone concentrations, calf birth weight and postpartum milk yield of Holstein cows. Journal of Animal Science. 54. 309-319. https://doi.org/10.2527/jas1982.542309x
- Cozzi, G., Ravarotto, L., Gottardo, F., Stefani, A., Contiero, L., Moro, L., Brscic, M. and Dalvit, P. 2011. Short communcation: Reference values for blood parameters in Holstein dairy cows: Effects of parity, stage of lactation and season of production. Journal of Dairy Science. 94. 3895-3901. https://doi.org/10.3168/jds.2010-3687
- De La Sota, R.L., Lucy, M.C., Staples, C.R. and Thatcher, W.W. 1993. Effects of recombinant bovine somatotropin (sometribove) on ovarian function in lactating and nonlactating dairy cows. Journal of Dairy Science. 76. 1002-1013. https://doi.org/10.3168/jds.S0022-0302(93)77428-7
- Devant, M., Ferret, J., Gasa, S.C. and Casals, R. 2000. Effects of protein concentration and degradability on performance, ruminal fermentation, and nitrogen metabolism in rapidly growing heifers fed high-concentrate diets from 100 to 230 kg body weight. Journal of Animal Science. 78. 1667-1676. https://doi.org/10.2527/2000.7861667x
- Drackley, J.K. 2004. Feeding for Accelerated Growth in Dairy Calves. Proceedings of Minnesota Dairy Health Conference. USA. 59-73.
- Gabler, M.T. and Heinrichs, A.J. 2003. Dietary Protein to Metabolizable Energy Ratios on Feed Efficiency and Structural Growth of Prepubertal Holstein Heifers. Journal of Dairy Science. 86. 268-274. https://doi.org/10.3168/jds.S0022-0302(03)73605-4
- Gardner, R.W., Schuh, J.D. and Vargus, L.G. 1977. Accelerated growth and early breeding of Holstein heifers. Journal of Dairy Science. 60. 1941-1948. https://doi.org/10.3168/jds.S0022-0302(77)84126-X
- Gaynor, P.J., Waldo, D.R., Capuco, A.V., Erdman, R.A. and Douglass, L.W. 1995. Effect of prepubertal growth rate and diet on lipid metabolism in lactating cows. Journal of Dairy Science. 78. 1534-1543. https://doi.org/10.3168/jds.S0022-0302(95)76775-3
- Groff, E.B. and Wu, Z. 2005. Milk production and nitrogen excretion of dairy cows fed different amounts of protein and varying proportions of alfalfa and corn silage. Journal of Dairy Science. 88. 3619-3632. https://doi.org/10.3168/jds.S0022-0302(05)73047-2
- Hill, T.M., Bateman, H.G., Quigley, J.D., Aldrich, J.M., Schlotterbeck, R.L. and Heinrichs, A.J. 2013. Review: New information on the protein requirements and diet formulation for dairy calves and heifers since the Dairy NRC 2001. The Professional Animal Scientists. 29. 199-207. https://doi.org/10.15232/S1080-7446(15)30225-4
- Hoffman, P.C., Esser, N.M., Bauman, L.M., Denzine, S.L. and Engstrom, M. Chester-Jones, H. 2001. Short Communication: Effect of dietary protein on growth and nitrogen balance of Holstein heifers. Journal of Dairy Science. 84. 843-847. https://doi.org/10.3168/jds.S0022-0302(01)74542-0
- Huhtanen, P. and Hristov, A.N. 2009. A meta-analysis of the effects of dietary protein concentration and degradability on milk protein yield and milk N efficiency in dairy cows. Journal of Dairy Science. 92. 3222-3232. https://doi.org/10.3168/jds.2008-1352
- Jeong, K.S. 2013. Effects of heifer ratio on efficiency of dairy management. Korean Journal of Agricultural Management and Policy. 40. 1006-1016.
- Kauffman, A.J. and St-Pierre, N.R. 2001. The relationship of milk urea nitrogen to urine nitrogen excretion in Holstein and Jersey cows. Journal of Dairy Science. 84. 2284-2294. https://doi.org/10.3168/jds.S0022-0302(01)74675-9
- Ki, K.S., Lee, H.J., Kim, S.B., Lee, W.S. Lim, D.H., Lim, H.J., Park, S.J., Cho, W.M., Kim, H.S., Jin, Z.L., Lee, I.D., Kim, W.Y. and Jeo, J.M. 2010. Effects of different energy and protein level of TMR on milk production of dairy goats in early lactation. Journal of the Korean Society of Grassland and Forage Science. 30. 267-274. https://doi.org/10.5333/KGFS.2010.30.3.267
- Kohn, R.A., Dinneen, M.M. and Russek-Cohen, E. 2005. Using blood urea nitrogen to predict nitrogen excretion and efficiency of nitrogen utilization in cattle, sheep, goats, horses, pigs, and rats. Journal of Animal Science. 83. 879-889. https://doi.org/10.2527/2005.834879x
- Lee, B.H., Nejad, J.G., Kim, H.S. and Sung, K.I. 2013. Effect of forage feeding level on the milk production characteristics of holstein lactating cows. Journal of the Korean Society of Grassland and Forage Science. 33. 45-51. https://doi.org/10.5333/KGFS.2013.33.1.45
- Marston, T.T. and Lusby, K.S. 1995. Effects of energy or protein supplements and stage of production on intake and digestibility of hay by beef cows. Journal of Animal Science. 73. 651-656. https://doi.org/10.2527/1995.733651x
- Moon, J.S., Joo, Y.S., Jang, G.C., Yoon, Y.D., Lee, B.K., Park, Y.H. and Son, C.H. 2002. Interpretation of protein-energy balance of feeding by milk urea nitrogen and milk protein contents in lactation holstein cow. Journal of Animal Science and Technology. 44. 573-584. https://doi.org/10.5187/JAST.2002.44.5.573
- National Livestock Research Institute. 2002. Standard tables of feed composition in Korea. Rural Development Administration.
- NRC (National Research Council). 2001. Nutrient requirements of dairy cattle. 7. 381.
- Park, S.B., Lim, D.H., Park, S.M., Kim, T.I., Choi, S.H., Kwon, E.G., Seo, J., Seo, S.W. and Ki, K.S. 2013. Effects of different energy and rumen undegradable protein levels on dairy cow's production performance at mid-lactation period. CNU Journal of Agricultural Science. 40. 333-338. https://doi.org/10.7744/cnujas.2013.40.4.333
- Reynal, S.M. and Broderick, G.A. 2005. Effect of dietary level of rumen-degraded protein on production and nitrogen metabolism in lactating dairy cows. Journal of Dairy Science. 88. 4045-4064. https://doi.org/10.3168/jds.S0022-0302(05)73090-3
- Rural Development Administration. 2007. Korean feeding standard for dairy cattle. National Institute of Animal Science.
- SAS. 2003. Statistical Analysis System, Version 9.1 USA.
- Son, C.H. 2012. Nutrition and reproduction of dairy cow. Journal of Veterinary Clinics. 29. 92-94.
- Steel, R.G.D. and Torrie, J.H. 1980. Principles and procedures of statistics: A biometric approach. Principles and procedures of statistics: a biometrical approach.