Influence of Particle Size on the Effectiveness of the Fiber in Barley Silage

¹ Department of Animal and Poultry Science, University of Saskatchewan, 72 Campus Drive, S7N 5B5, Saskatoon, SK, Canada

We used eight multiparous Holstein cows in a 4 x 4 Latin square design to evaluate the effects and possible interactions between silage particle size and concentrate level on chewing activities and productivity of cows fed barley-based total mixed rations (TMR). Diets were designed with two forage-to-concentrate ratios (low forage, 45:55, high forage 55:45), combined with two theoretical chop lengths of barley silage (short = 4.68 mm and long = 18.75 mm). Diets were formulated to provide similar and above-minimum neutral detergent fiber recommended for cows in early lactation. Increasing silage particle size of the forage did not affect dry matter intake. The 3.5% fat-correct milk and fat yields trended higher for increased particle size. Percent milk protein was higher for short particle size. Increasing the concentrate levels in the diets increased proportions of milk protein and lactose, but not milk fat. Cows fed short silage spent 90 min less per day chewing and ruminating than did those on long silage. Total chewing activity per kilogram of forage intake was higher for cows on long silage compared with those on short silage diets. Although a reduction in silage particle size did not depress milk fat, rumination and chewing activity were significantly reduced. These results suggest that particle size of the silage may have dominant control over chewing activity despite adequate neutral detergent fiber intakes.

Key Words: particle size • barley silage • effective fiber

Submitted on January 24, 2000
Accepted on May 1, 2000

This article has been cited by other articles:

				Q. Zebeli, J. Dijkstra, M. Tafaj, H. Steingass, B. N. Ametaj, and W. Drochner Modeling the Adequacy of Dietary Fiber in Dairy Cows Based on the Responses of Ruminal pH and Milk Fat Production to Composition of the Diet J Dairy Sci, May 1, 2008; 91(5): 2046 - 2066. [Abstract] [Full Text] [PDF]

				W. Z. Yang and K. A. Beauchemin Physically effective fiber: method of determination and effects on chewing, ruminal acidosis, and digestion by dairy cows. J Dairy Sci, July 1, 2006; 89(7): 2618 - 2633. [Abstract] [Full Text] [PDF]

				W. Z. Yang and K. A. Beauchemin Increasing the physically effective fiber content of dairy cow diets may lower efficiency of feed use. J Dairy Sci, July 1, 2006; 89(7): 2694 - 2704. [Abstract] [Full Text] [PDF]

				Q. Zebeli, M. Tafaj, H. Steingass, B. Metzler, and W. Drochner Effects of Physically Effective Fiber on Digestive Processes and Milk Fat Content in Early Lactating Dairy Cows Fed Total Mixed Rations J Dairy Sci, February 1, 2006; 89(2): 651 - 668. [Abstract] [Full Text] [PDF]

				W. Z. Yang and K. A. Beauchemin Effects of Physically Effective Fiber on Chewing Activity and Ruminal pH of Dairy Cows Fed Diets Based on Barley Silage J Dairy Sci, January 1, 2006; 89(1): 217 - 228. [Abstract] [Full Text] [PDF]

				H. W. Soita, M. Fehr, D. A Christensen, and T. Mutsvangwa Effects of Corn Silage Particle Length and Forage:Concentrate Ratio on Milk Fatty Acid Composition in Dairy Cows Fed Supplemental Flaxseed J Dairy Sci, August 1, 2005; 88(8): 2813 - 2819. [Abstract] [Full Text] [PDF]

				C. Leonardi, K. J. Shinners, and L. E. Armentano Effect of Different Dietary Geometric Mean Particle Length and Particle Size Distribution of Oat Silage on Feeding Behavior and Productive Performance of Dairy Cattle J Dairy Sci, February 1, 2005; 88(2): 698 - 710. [Abstract] [Full Text] [PDF]

				C. M. Graf, M. Kreuzer, and F. Dohme Effects of Supplemental Hay and Corn Silage Versus Full-Time Grazing on Ruminal pH and Chewing Activity of Dairy Cows J Dairy Sci, February 1, 2005; 88(2): 711 - 725. [Abstract] [Full Text] [PDF]

				M. S. Einarson, J. C. Plaizier, and K. M. Wittenberg Effects of Barley Silage Chop Length on Productivity and Rumen Conditions of Lactating Dairy Cows Fed a Total Mixed Ration J Dairy Sci, September 1, 2004; 87(9): 2987 - 2996. [Abstract] [Full Text] [PDF]

				P. J. Kononoff and A. J. Heinrichs The Effect of Corn Silage Particle Size and Cottonseed Hulls on Cows in Early Lactation J Dairy Sci, July 1, 2003; 86(7): 2438 - 2451. [Abstract] [Full Text] [PDF]

				K. A. Beauchemin, W. Z. Yang, and L. M. Rode Effects of Particle Size of Alfalfa-Based Dairy Cow Diets on Chewing Activity, Ruminal Fermentation, and Milk Production J Dairy Sci, February 1, 2003; 86(2): 630 - 643. [Abstract] [Full Text] [PDF]

				P. W. Clark and L. E. Armentano Influence of Particle Size on the Effectiveness of the Fiber in Alfalfa Silage J Dairy Sci, November 1, 2002; 85(11): 3000 - 3007. [Abstract] [Full Text] [PDF]