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Abstract
Twenty lactating Holstein cows were used to determine the nutritional value of eastern
gamagrass. Dietary treatments consisted of 1) gamagrass hay and no corn (HNC), 2) gamagrass silage (S) and no corn (SNC), 3) S and low corn (SLC), 4) S and medium corn (SMC), and 5) S and high corn (SHC). Gamagrass fed as hay or silage did not change (P>0.10) milk yield, but corn inclusion
tended to increase (P<0.08) milk yield. Yields of milk protein (0.69 vs 0.80 kg/d),
lactose (1.23 vs 1.44 kg/d), and solids-not-fat (2.12 vs 2.48 kg/d) tended to be greater
for SNC than for HNC (P<0.08). Corn inclusion increased milk yields compared with
SNC. Gamagrass fed as silage resulted in a greater feed conversion efficiency than
did gamagrass fed as hay (2.16 vs 1.88; P<0.01). Adding corn to S reduced feed efficiency.
Conversion of feed N to milk N was greater (P<0.01) for gamagrass fed as silage than
for hay. Milk urea N (MUN) concentration was greater (P<0.01) for cows fed HNC than for cows on all other treatments.
Feeding S significantly lessened MUN concentration. Including corn at the medium and
high levels further reduced MUN concentration (P<0.05). Increased energy from corn
at the high level increased milk yield and tended to increase conversion of feed N
into milk protein. Gamagrass fed as silage without or with corn improved the N status
of the cows, as indicated by lesser MUN concentrations.
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Literature Cited
- Effects of diet on short-term regulation of feed intake by lactating dairy cattle.J. Dairy Sci. 2000; 83: 1598
- International Official Methods of Analysis.Association of Official Analytical Chemists. 16th Ed. Arlington, VA.1984
- Official Methods of Analysis.Association of Official Analytical Chemists. 14th Ed. Arlington, VA.1984
- Protein systems for feeding ruminant livestock: A European assessment.J. Dairy Sci. 1994; 77: 2031
- Eastern gamagrass silage fermentation characteristics and quality under different nitrogen rates.J. Prod. Agric. 1994; 7: 477
- Performance of lactating dairy cows fed either alfalfa silages or alfalfa hay as the sole forage.J. Dairy Sci. 1995; 78: 320
- Quality of eastern gamagrass compared with switchgrass and flaccidgrass when preserved as hay.Postharvest Biol. and Tech. 1996; 7: 261
- The importance of rate of ruminal fermentation of energy sources in diets for dairy cows.in: Garnsworthy P.C. Cole D.J.A. In Recent Advances in Animal Nutrition. Nottingham Univ. Press, Nottingham, United Kingdom1963: 6
- In situ dry matter, nitrogen, and fiber degradation of alfalfa, red clover, and eastern gamagrass at four maturities.J. Dairy Sci. 1998; 81: 150
- Effects of the composition of grass silages on milk production and nitrogen utilization by dairy cows.Anim. Sci. 1996; 62: 25
- Steady-state rates of linoleic acid biohydrogenation by ruminal bacteria in continuous culture.J. Dairy Sci. 1995; 78: 1815
- Comparative nutritional value of eastern gamagrass and alfalfa hay for dairy cows.J. Dairy Sci. 1985; 68: 2615
- Protein and nonprotein nitrogen utilization in dairy cattle.J. Dairy Sci. 1981; 64: 1170
- Evaluating acid and base catalysts in the methylation of milk and rumen fatty acids with special emphasis on conjugated dienes and total trans fatty acids.Lipids. 1997; 32: 1219
- Standardization of procedures for N fractionation of ruminant feeds.Anim. Feed Sci. Technol. 1996; 57: 347
- Balancing carbohydrates in dairy rations.In Proc. Large Dairy Herd Manage. Conf. Cornell Univ., Ithaca, NY1963: 150
- National Research Council Nutrient requirements of dairy cattle.Natl. Acad. Sci. 6th Rev. Ed. Washington, DC1989
- Impact of stage of maturity and method of preservation of alfalfa on digestion in lactating cows.J. Dairy Sci. 1992; 75: 1571
- In Proc. 2nd Eastern Native Grass Symposium. November 17-19, 1999, Baltimore, MD. p 253. USDA.Agricultural Research Service. Beltsville, MD1996
- Ruminal fermentation and digestion in lactating cows fed grass silage with protein and energy supplements.J. Dairy Sci. 1995; 78: 342
- Effects of grain level and protein source on ruminal fermentation, degradability, and digestion in milking cows fed silage.J. Dairy Sci. 1991; 74: 2256
- SAS. User’s Guide: Statistics.(Release 8.01). SAS Inst., Inc., Cary, NC1999
- Effect of forage conservation method, concentrate level and propylene glycol on diet digestibility, rumen fermentation, blood metabolite concentrations and nutrient utilisation of dairy cows.Anim. Feed Sci. Technol. 2002; 97: 1
- Degradation of nitrogenous compounds in conserved forages in the rumen of dairy cows.Grass Forage Sci. 1991; 46: 427
- Prediction of the energy value of cow’s milk.J. Dairy Sci. 1965; 48: 1215
- Forage preservation. In Nutritional Ecology of the Ruminant.2nd ed. Cornell University Press, Ithaca, NY1996: 213
- Methods for dietary fiber, neutral detergent fiber, and non-starch polysaccha-rides in relation to animal nutrition.J. Dairy Sci. 1991; 74: 3583
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© 2003 American Registry of Professional Animal Scientists. Published by Elsevier Inc. All rights reserved.
