Heifers grazing winter range require supplemental nutrients to complement dormant forage to achieve optimal growth and performance. A study was conducted to evaluate nutritional environment and effect of different supplementation strategies for developing heifers grazing dormant winter range. Eighty-four Angus crossbred heifers were stratified by body weight at weaning, allocated to one of six replicated pastures, and randomly assigned one of three supplemental treatments: 1) 908 g/d of a control supplement providing 340 g·hd-1·d-1 of CP with 130 g of rumen undegradable protein (RUP) and 614 MJ of ME (LRUP); 2) 908 g/d of a RUP supplement providing 340 g·hd-1·d-1 of CP with 170 g of RUP and 567 MJ of ME (HRUP); or 3) 1814 g/d of a protein and energy supplement providing 340 g·hd-1·d-1 of CP with 120 g of RUP + 100 g of propionate salt (NutroCalTM, Kemin Industries, Inc.) and 1222 MJ of ME (LRUP + E). Body weights were taken in November, with monthly 12 h shrunk BW from January thru April, and again in September (at time of pregnancy diagnosis). Heifer average daily gain was similar throughout the developmental period except from d125 to d159 where LRUP + E supplemented heifers had greater gains (P < 0.01) than LRUP and HRUP supplemented heifers (0.33, 0.04, and 0.14 ± 0.05 kg/d, respectively). LRUP + E heifers had a greater percentage (P = 0.04) of heifers pubertal at time of artificial insemination compared to LRUP and HRUP heifers (57, 29, and 30, respectively). However, no differences were detected in overall pregnancy rates (P = 0.40). This study indicated that feeding more supplemental energy (i.e., propionate salt, ground milo and corn) allowed lightweight heifers to achieve a greater rate of gain at a key period during development and achieved comparable reproductive success to heifers only receiving supplemental protein.
Cite this paper
Waterman, R. , Sawyer, J. , Kane, K. , Hawkins, D. and Petersen, M. (2014) Heifer Body Weight Gain and Reproductive Achievement in Response to Protein and Energy Supplementation While Grazing Dormant Range Forage. Agricultural Sciences
, 1296-1304. doi: 10.4236/as.2014.513138
 Wallace, J.D. and Parker, E.E. (1992) Range Supplements—What We Have Learned. Livestock Research Briefs & Cattle Growers Short Courses, 20-27.
 NRC (2000) Nutrient Requirements of Beef Cattle. 7th Edition, National Academies Press, Washington DC.
 Krysl, L.J., et al. (1987) Cattle Nutrition on Blue Grama Rangeland in New Mexico. New Mexico Agricultural Experiment Station Bulletin, 727, 1-35.
 Cochran, R.C. (1995) Developing Optimal Supplementation Programs for Range Livestock. Kansas State University Field Day. 50 Years of Range Research Revisited. Cooperative Extension Service, Kansas State University, Manhattan, 58-72.
 Clanton, D.C. (1982) Crude Protein System in Range Supplements. In: Owens, F.N., Ed., Symposium of Protein Requirements for Cattle, Stillwater, 228-234.
 Leng, R.A., Economides, S. and Ball, F.M. (1978) The Effects on Growth of Supplying Glucose Continuously into the Duodenum of Lambs on Low-Protein Diets. Proceedings of Australian Society of Animal Production, 12, 134.
 Lesmeister, J.L., Burfening, P.J. and Blackwell, R.L. (1973) Date of First Calving in Beef Cows and Subsequent Calf Production. Journal of Animal Science, 36, 1-6.
 Short, R.E. and Bellows, R.A. (1971) Relationships among Weight Gains, Age at Puberty and Reproductive Performance in Heifers. Journal of Animal Science, 32, 127-131.
 Wiltbank, J.N., et al. (1966) Effects of Heterosis on Age and Weight at Puberty in Beef Heifers. Journal of Animal Science, 25, 744-751.
 McCartor, M.M., Randel, R.D. and Carroll, L.H. (1979) Dietary Alteration of Ruminal Fermentation on Efficiency of Growth and Onset of Puberty in Brangus Heifers. Journal of Animal Science, 48, 488-494.
 Moseley, W.M., et al. (1982) Relationship of Growth and Puberty in Beef Heifers Fed Monensin. Journal of Animal Science, 55, 357-362.
 Floyd, C.R., et al. (1995) Effects of Monensin and 4-Plex on Growth and Puberty of Beef Heifers. Oklahoma State University Animal Science Research Report, Oklahoma State University, Stillwater, 943, 75-80.
 Lalman, D.L., et al. (1993) The Effects of Ruminally Undegradable Protein, Propionic Acid, and Monensin on Puberty and Pregnancy in Beef Heifers. Journal of Animal Science, 71, 2843-2852.
 Clanton, D.C., Jones, L.E. and England, M.E. (1983) Effect of Rate and Time of Gain after Weaning on the Development of Replacement Beef Heifers. Journal of Animal Science, 56, 280-285.
 Wessels, R.H., et al. (1996) Lasalocid Effects on Ruminal Degradation of Protein and Postruminal Supply of Amino Acids in Holstein Steers. Journal of Dairy Science, 79, 1802-1808. http://dx.doi.org/10.3168/jds.S0022-0302(96)76548-7
 Moseley, W.M., McCartor, M.M. and Randel, R.D. (1977) Effects of Monensin on Growth and Reproductive Performance of Beef Heifers. Journal of Animal Science, 45, 961-968.
 Jenkins, T.C. and Thonney, M.L. (1988) Effect of Propionate Level in a Volatile Fatty Acid Salt Mixture Fed to Lambs on Weight Gain, Body Composition and Plasma Metabolites. Journal of Animal Science, 66, 1028-1035.
 Forbes, A. (1999) Taxonomy of the Flora of the Corona Range and Livestock Research Center. M.S. Thesis, New Mexico State University, Las Cruces.
 Knox, L.A. (1998) The Responses of Beef Cattle Grazing Native Rangeland to Management Fecisions. M.S. Thesis, New Mexico State University, Las Cruces.
 Lesperance, A.L., Bohman, V.R. and Marble, D.W. (1960) Development of Techniques for Evaluating Grazed Forage. Journal of Dairy Science, 43, 682-689. http://dx.doi.org/10.3168/jds.S0022-0302(60)90219-8
 AOAC (1990) Official Methods of Analysis. 15th Edition, Association of Official Analysis Chemists, Arlington.
 Goering, H.K. and Van Soest, P.J. (1970) Forage Fiber Analyses (Apparatus, Reagents, Procedures, and Some Applications). Agriculture. Handbook No. 379, USDA-ARS, Washington DC.
 Schneider, F.A. and Hallford, D.M. (1996) Use of a Rapid Progesterone Radioimmunoassay to Predict Pregnancy and Fetal Numbers in Ewes. Sheep and Goat Research, 12, 33-38.
 Herd, D.H. and Sprott, L.R. (1986) Body Condition, Nutrition and Reproduction of Beef Cows. Texas Agricultural Extenstion Service, B-1526, 1-11.
 Reimers, T.J., et al. (1982) Validation of a Rapid Solid-Phase Radioimmunoassay for Canine, Bovine, and Equine Insulin. American Journal Veterinary Research, 43, 1274-1278.
 Williams, C.H., David, D.J. and Iismaa, O. (1962) The Determination of Chromic Oxide in Feces Samples by Atomic Absorption Spectrophotometry. Journal of Agriculture Science, 59, 381-385. http://dx.doi.org/10.1017/S002185960001546X
 Sunvold, G.D., Cochran, R.C. and Vanzant, E.S. (1991) Evaluation of Wheat Middlings as a Supplement for Beef Cattle Consuming Dormant Bluestem-Range Forage. Journal of Animal Science, 69, 3044-3054.
 Hammond, A.C., Kunkle, W.E., Bates, D.B. and Sollenberger, L.E. (1993) Use of Blood Urea Nitrogen Concentration to Predict Response to Protein or Energy Supplementation in Grazing Cattle. Proceedings of the 17th International Grassland Congress, Rockhampton, 1989-1991.
 Stateler, D.A., Kunkle, W.E. and Hammond, A.C. (1995) Effect of Protein Level and Source in Molasses Slurries on the Performance of Growing Cattle Fed Hay during Winter. Journal of Animal Science, 73, 3078-3084.
 Peters, J.P. and Elliot, J.M. (1984) Endocrine Changes with Infusion of Propionate in the Dairy Cow. Journal of Dairy Science, 67, 2455-2459. http://dx.doi.org/10.3168/jds.S0022-0302(84)81596-9