|
|
||||||||
1 The Atlantic Dairy and Forage Institute, 115 Sunbury Drive, Fredericton Junction, NB, Canada E0G 1T0
Nine midlactation dairy cows were offered one of three mixed silage rations with neutral detergent fiber (NDF) that was similar in concentration but different in fermentability. Differences in fermentability were achieved by substituting a high quality alfalfa silage for a low quality alfalfa silage and substituting a combination of ryegrass and timothy silages for a barley silage. In addition, concentrate was allocated at 0.30, 0.82, or 1.37 kg of dry matter/kg of dry matter intake (DMI) from the mixed silage ration. As expected, the NDF content of the mixed silage ration did not differ, although fermentability of NDF increased numerically as forage quality increased. Intake of NDF increased linearly, and DMI tended to increase linearly, as fiber fermentability of the mixed silage ration increased. In addition, cows produced more milk, milk fat, and milk protein and generated more total and milk energy. The calculated concentration of net energy for lactation of the total diet also increased. Results support the concept that NDF quality influences and can be used to predict voluntary feed intake, at least in relatively high producing dairy cows. The DMI increased, and intake of NDF and crude protein declined, as the allocation of concentrate increased. In addition, as concentrate allocation increased, cows spent less time eating and ruminating and more time resting and produced more milk, milk protein, and milk lactose. Cows also generated more total energy and milk energy, although, despite a sharp decrease in the forage proportion of the diet, the calculated energy density of the diet did not differ among concentrate levels. The lack of significant interactions between concentrate level and fiber fermentability for any parameter measured supports the contention that high quality forage is critical to a successful dairy ration, regardless of the proportion of forage in the diet.
Key Words: neutral detergent fiber fiber quality intake concentrate
Submitted on January 23, 1995
Accepted on August 23, 1996
This article has been cited by other articles:
![]() |
A. Bach, C. Iglesias, S. Calsamiglia, and M. Devant Effect of Amount of Concentrate Offered in Automatic Milking Systems on Milking Frequency, Feeding Behavior, and Milk Production of Dairy Cattle Consuming High Amounts of Corn Silage J Dairy Sci, November 1, 2007; 90(11): 5049 - 5055. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. J. R. Cherney, J. H. Cherney, and L. E. Chase Lactation Performance of Holstein Cows Fed Fescue, Orchardgrass, or Alfalfa Silage J Dairy Sci, July 1, 2004; 87(7): 2268 - 2276. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. A. Whitlock, D. J. Schingoethe, A. R. Hippen, K.F. Kalscheur, and A.A. AbuGhazaleh Milk Production and Composition from Cows Fed High Oil or Conventional Corn at Two Forage Concentrations J Dairy Sci, July 1, 2003; 86(7): 2428 - 2437. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. I. Harvatine, J. E. Winkler, M. Devant-Guille, J. L. Firkins, N. R. St-Pierre, B. S. Oldick, and M. L. Eastridge Whole Linted Cottonseed as a Forage Substitute: Fiber Effectiveness and Digestion Kinetics J Dairy Sci, August 1, 2002; 85(8): 1988 - 1999. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |