| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
ANIMAL PRODUCTION |
Department of Animal Science, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2
2 Corresponding author: km_wittenberg{at}umanitoba.ca
Use of ionophores in cattle diets has been proposed as a strategy for mitigation of enteric CH4 emissions. Short- and long-term effects of feeding a single ionophore (monensin) or rotation of 2 ionophores (monensin and lasalocid) on enteric CH4 emissions were evaluated in 36 Angus yearling steers (328 ± 24.9 kg of BW) over a 16-wk period. Steers were randomly assigned to 6 dietary treatments of 6 steers each. The 6 diets were low-concentrate without ionophore supplementation, low-concentrate with monensin supplementation, low-concentrate with a 2-wk rotation of monensin and lasalocid supplementation, high-concentrate without ionophore supplementation, high-concentrate with monensin supplementation, and high-concentrate with a 2-wk rotation of monensin and lasalocid supplementation. Daily enteric CH4 emissions, as measured using the SF6 tracer gas technique, ranged from 54.7 to 369.3 L/steer daily. Supplementing ionophores decreased (P < 0.05) enteric CH4 emissions, expressed as liters per kilogram of DMI or percentage of GE intake, by 30% for the first 2 wk and by 27% for the first 4 wk, for cattle receiving the high-concentrate and low-concentrate diets, respectively. Cattle fed a rotation of ionophores did not (P > 0.05) exhibit a greater decrease and did not (P > 0.05) have a longer period of depressed enteric CH4 emissions compared with cattle receiving monensin only. Ionophore supplementation did not (P > 0.05) alter total ruminal fluid VFA concentration; however, the acetate:propionate ratio and ammonia-N concentration in ruminal fluid were decreased (P < 0.001) from the time that ionophores were introduced to the time they were removed from the diets. Both monensin and the rotation of monensin and lasalocid decreased (P < 0.001) total ciliate protozoal populations by 82.5% in the first 2 wk and by 76.8% in the first 4 wk during which they were supplemented in the high-concentrate and low-concentrate diets, respectively. Original ciliate protozoal populations were restored by the fourth and sixth week of supplementation when cattle were fed the high- or low-concentrate diets, respectively. No significant change was observed thereafter. These data suggest that the effects of ionophores on enteric CH4 production are related to ciliate protozoal populations and that ciliate protozoal populations can adapt to the ionophores present in either low- or high-concentrate diets. Rotation of monensin and lasalocid did not (P > 0.05) prevent ciliate protozoal adaptation to ionophores.
Key Words: cattle • enteric methane • ionophore • lasalocid • monensin • protozoa
This article has been cited by other articles:
|
|
 |
|
  M. J. Quinn, M. L. May, K. E. Hales, N. DiLorenzo, J. Leibovich, D. R. Smith, and M. L. Galyean Effects of ionophores and antibiotics on in vitro hydrogen sulfide production, dry matter disappearance, and total gas production in cultures with a steam-flaked corn-based substrate with or without added sulfur J Anim Sci, May 1, 2009; 87(5): 1705 - 1713. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Grainger, M. J. Auldist, T. Clarke, K. A. Beauchemin, S. M. McGinn, M. C. Hannah, R. J. Eckard, and L. B. Lowe Use of Monensin Controlled-Release Capsules to Reduce Methane Emissions and Improve Milk Production of Dairy Cows Offered Pasture Supplemented with Grain J Dairy Sci, March 1, 2008; 91(3): 1159 - 1165. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Martineau, C. Benchaar, H. V. Petit, H. Lapierre, D. R. Ouellet, D. Pellerin, and R. Berthiaume Effects of Lasalocid or Monensin Supplementation on Digestion, Ruminal Fermentation, Blood Metabolites, and Milk Production of Lactating Dairy Cows J Dairy Sci, December 1, 2007; 90(12): 5714 - 5725. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. L. Firkins, Z. Yu, and M. Morrison Ruminal Nitrogen Metabolism: Perspectives for Integration of Microbiology and Nutrition for Dairy J Dairy Sci, June 1, 2007; 90(13_suppl): E1 - E16. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. E. Odongo, R. Bagg, G. Vessie, P. Dick, M. M. Or-Rashid, S. E. Hook, J. T. Gray, E. Kebreab, J. France, and B. W. McBride Long-Term Effects of Feeding Monensin on Methane Production in Lactating Dairy Cows J Dairy Sci, April 1, 2007; 90(4): 1781 - 1788. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
