| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
New Mexico State University, Las Cruces 88003-0009 and University of Nevada-Reno, Reno 89557-0104
Abstract
Six beef steers (British x Brahman) cannulated at the rumen, duodenum and ileum (avg wt 334 kg) and three mature steers (British x British) cannulated at the esophagus were used in a replicated 3 x 3 latin square design and fed no supplement (C), .5 kg soybean meal (SBM) or .5 kg steam-flaked sorghum grain (SFS)·head–1·d–1 (DM basis) while grazing blue grama rangeland. Periods of the latin square included a minimum of 14 d for adaptation and 11 d for esophageal masticate collection and digesta sampling. In September, October and November, respectively, forage collected by esophageally cannulated steers averaged 74.5, 88.8 and 71.0% grasses; 2.06, 1.53 and 1.77% N and 68.3, 82.6 and 77.1% NDF (OM basis). Forage OM, ADF, NDF and N intakes were not affected (P > .10) by treatment, but total N intake was greater (P < .05) for SBM vs C and SFS treatments. No differences (P > .10) were detected among treatments in OM, NDF, ADF and N digestibilities in the rumen, small intestine or hindgut, but total tract OM digestibility was greater (P < .10) for SBM and SFS than for C, and total tract N digestibility was greater (P < .10) for SBM than for C or SFS. Duodenal ammonia N flow was greater (P < .05) when SBM was fed that when SFS and C were fed, but microbial N and non-ammonia, non-microbial N flows and microbial efficiency were not altered by treatment. Likewise, ileal N flow was not affected (P > .10) by treatment. Particulate passage rate, gastrointestinal mean retention time, forage in vitro OM disappearance and in situ rate of forage NDF digestion also were not affected (P > .10) by treatments. Ruminal fluid volume was greater (P < .05) for SFS vs SBM and C treatments, but no differences were noted in fluid dilution rate. Ruminal fluid ammonia concentration was greater (P < .05) when SBM was fed than when SFS and C were fed (13.5, 9.9 and 8.7 mg/dl, respectively), whereas pH and total VFA concentrations were not different (P > .10). Proportion of acetate in ruminal fluid was less (P < .10) for SBM and SFS than for C. Small amounts of supplemental SBM and SFS had little effect on forage intake, ruminal fermentation and site of digestion but both increased total tract OM digestion in steers grazing blue grama rangeland.
1 Journal article 1426 of the New Mexico Agric. Exp. Sta., Las Cruces.
2 Dept. of Anim. and Range Sci.
3 Dept. of Anim. Sci., Univ. of Nevada, Reno 89557.
4 Dept. of Anim. Sci., Univ. of Illinois, Urbana 61801.
This article has been cited by other articles:
|
|
 |
|
  T. C. Gilbery, G. P. Lardy, S. A. Soto-Navarro, M. L. Bauer, and J. S. Caton Effects of corn condensed distillers solubles supplementation on ruminal fermentation, digestion, and in situ disappearance in steers consuming low-quality hay J Anim Sci, June 1, 2006; 84(6): 1468 - 1480. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. J. Reed, G. P. Lardy, M. L. Bauer, T. C. Gilbery, and J. S. Caton Effect of field pea level on intake, digestion, microbial efficiency, ruminal fermentation, and in situ disappearance in beef steers fed forage-based diets J Anim Sci, July 1, 2004; 82(7): 2185 - 2192. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. W. Bohnert, C. S. Schauer, M. L. Bauer, and T. DelCurto Influence of rumen protein degradability and supplementation frequency on steers consuming low-quality forage: I. Site of digestion and microbial efficiency J Anim Sci, November 1, 2002; 80(11): 2967 - 2977. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. W. Bohnert, C. S. Schauer, S. J. Falck, and T. DelCurto Influence of rumen protein degradability and supplementation frequency on steers consuming low-quality forage: II. Ruminal fermentation characteristics J Anim Sci, November 1, 2002; 80(11): 2978 - 2988. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
