| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Department of Animal and Dairy Science, The University of Georgia, Tifton 31793-0748
Corresponding author: J. K. Bernard; e-mail: jbernard{at}tifton.uga.edu.
Forty Holstein cows were used in an 8-wk randomized block design trial to determine the effects of theoretical length of cut (TLC) and kernel processing (KP) of whole plant corn silage on nutrient intake and digestibility, milk yield, and milk composition. Corn was harvested at three-quarters milk line stage of maturity at TLC of 1.90 or 2.54 cm. At each TLC, corn was KP at either 2 or 8 mm roll clearance. The control was harvested at 1.90 cm without KP. Corn silage provided 38% of the dietary dry matter (DM) in the experimental diets. Intake of DM and nutrients was similar among treatments. Apparent digestibility of DM and acid detergent fiber (ADF) increased with increasing TLC. Fiber digestibility was improved by KP compared with unprocessed corn silage. Starch digestibility was greater for corn silage KP at 2 vs. 8 mm. Apparent digestibility of DM, crude protein, and ADF was lowest for the diet containing silage harvested at 2.54 cm TLC and KP at 8 mm, resulting in an interaction of TLC and KP. No differences were observed in DM intake (DMI) among treatments. An interaction of TLC and KP was observed, however, for yield of milk protein and energy-corrected milk (ECM) and efficiency of converting DMI to ECM because of lower yield for diets containing silage harvested at 2.54 cm TLC and KP at 8 mm. Results of this trial indicate that as TLC increases, aggressive KP is necessary to maintain nutrient digestibility and performance of lactating dairy cows.
Key Words: corn silage • kernel processing • theoretical length of cut
Abbreviation key: KP = kernel processing, TLC = theoretical length of cut, 1.95C = corn silage chopped at 1.95 cm with no kernel processing, 1.95M = corn silage chopped at 1.95 cm with 2-mm kernel processing, 1.95P = corn silage chopped at 1.95 cm with 8-mm kernel processing, 2.54M = corn silage chopped at 2.54 cm with 2-mm kernel processing, 2.54P = corn silage chopped at 2.54 cm with 8-mm kernel processing
This article has been cited by other articles:
|
|
 |
|
  A. Zwald, A. E. Dorshorst, P. C. Hoffman, L. M. Bauman, and M. G. Bertram Technical Note: A Near-Infrared Reflectance Spectroscopy Technique to Predict Particle Size of Starch Within Corn Silage J Dairy Sci, May 1, 2008; 91(5): 2071 - 2076. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. J. Couderc, D. H. Rearte, G. F. Schroeder, J. I. Ronchi, and F. J. Santini Silage chop length and hay supplementation on milk yield, chewing activity, and ruminal digestion by dairy cows. J Dairy Sci, September 1, 2006; 89(9): 3599 - 3608. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Ferreira and D. R. Mertens Chemical and Physical Characteristics of Corn Silages and Their Effects on In Vitro Disappearance J Dairy Sci, December 1, 2005; 88(12): 4414 - 4425. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
