|
|
||||||||
ANIMAL PRODUCTION |
Department of Animal and Range Sciences, North Dakota State University, Fargo 58105
2 Corresponding author: glardy{at}ndsuext.nodak.edu
Fourteen Holstein steers (446 ± 4.4 kg of initial BW) with ruminal, duodenal, and ileal cannulas were used in a completely randomized design to evaluate effects of whole or ground canola seed (23.3% CP and 39.6% ether extract; DM basis) on intake, digestion, duodenal protein supply, and microbial efficiency in steers fed low-quality hay. Our hypothesis was that processing would be necessary to optimize canola use in diets based on low-quality forage. The basal diet consisted of ad libitum access to switchgrass hay (5.8% CP; DM basis) offered at 0700 daily. Treatments consisted of hay only (control), hay plus whole canola (8% of dietary DM), or hay plus ground canola (8% of dietary DM). Supplemental canola was provided based on the hay intake of the previous day. Steers were adapted to diets for 14 d followed by a 7-d collection period. Total DMI, OM intake, and OM digestibility were not affected (P
0.31) by treatment. Similarly, no differences (P
0.62) were observed for NDF or ADF total tract digestion. Bacterial OM at the duodenum increased (P = 0.01) with canola-containing diets compared with the control diet and increased (P = 0.08) in steers consuming ground canola compared with whole canola. Apparent and true ruminal CP digestibilities were increased (P = 0.01) with canola supplementation compared with the control diet. Canola supplementation decreased ruminal pH (P = 0.03) compared with the control diet. The molar proportion of acetate in the rumen tended (P = 0.10) to decrease with canola supplementation. The molar proportion of acetate in ruminal fluid decreased (P = 0.01), and the proportion of propionate increased (P = 0.01), with ground canola compared with whole canola. In situ disappearance rate of hay DM, NDF, and ADF were not altered by treatment (P
0.32). In situ disappearance rate of canola DM, NDF, and ADF increased (P = 0.01) for ground canola compared with whole canola. Similarly, ground canola had greater (P = 0.01) soluble CP fraction and CP disappearance rate compared with whole canola. No treatment effects were observed for ruminal fill, fluid dilution rate, or microbial efficiency (P
0.60). The results suggest that canola processing enhanced in situ degradation but had minimal effects on ruminal or total tract digestibility in low-quality, forage-based diets.
Key Words: canola digestion low-quality hay processing steer supplementation
This article has been cited by other articles:
![]() |
E. Scholljegerdes and S. Kronberg Influence of level of supplemental whole flaxseed on forage intake and site and extent of digestion in beef heifers consuming native grass hay J Anim Sci, September 1, 2008; 86(9): 2310 - 2320. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. W. Hess, G. E. Moss, and D. C. Rule A decade of developments in the area of fat supplementation research with beef cattle and sheep J Anim Sci, April 1, 2008; 86(14_suppl): E188 - E204. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. C. Gilbery, G. P. Lardy, S. A. Soto-Navarro, M. L. Bauer, and V. L. Anderson Effect of field peas, chickpeas, and lentils on rumen fermentation, digestion, microbial protein synthesis, and feedlot performance in receiving diets for beef cattle J Anim Sci, November 1, 2007; 85(11): 3045 - 3053. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |