| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
* University of Guelph, Guelph, Ontario, N1G 2W1 Canada
University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5A8 Canada
Elanco Animal Health, Division Eli Lilly Canada Inc., Guelph, Ontario, N1G 4T2 Canada
1 Corresponding author: bmcbride{at}uoguelph.ca
The objective of this study was to investigate the effect of monensin (MN) and dietary soybean oil (SBO) on milk fat percentage and milk fatty acid (FA) profile. The study was conducted as a randomized complete block design with a 2 x 3 factorial treatment arrangement using 72 lactating multiparous Holstein dairy cows (138 ± 24 d in milk). Treatments were [dry matter (DM) basis] as follows: 1) control total mixed ration (TMR, no MN) with no supplemental SBO; 2) MN-treated TMR (22 g of MN/kg of DM) with no supplemental SBO; 3) control TMR including 1.7% SBO; 4) MN-treated TMR including 1.7% SBO; 5) control TMR including 3.4% SBO; and 6) MN-treated TMR including 3.4% SBO. The TMR (% of DM; corn silage, 31.6%; haylage, 21.2%; hay, 4.2%; high-moisture corn, 18.8%; soy hulls, 3.3%; and protein supplement, 20.9%) was offered ad libitum. The experiment consisted of a 2-wk baseline, a 3-wk adaptation, and a 2-wk collection period. Monensin, SBO, and their interaction linearly reduced milk fat percentage. Cows receiving SBO with no added MN (treatments 3 and 5) had 4.5 and 14.2% decreases in milk fat percentage, respectively. Cows receiving SBO with added MN (treatments 4 and 6) had 16.5 and 35.1% decreases in milk fat percentage, respectively. However, the interaction effect of MN and SBO on fat yield was not significant. Monensin reduced milk fat yield by 6.6%. Soybean oil linearly reduced milk fat yield and protein percentage and linearly increased milk yield and milk protein yield. Monensin and SBO reduced 4% fat-corrected milk and had no effect on DM intake. Monensin interacted with SBO to linearly increase milk fat concentration (g/100 g of FA) of total trans-18:1 in milk fat including trans-6 to 8, trans-9, trans-10, trans-11, trans-12 18:1 and the concentration of total conjugated linoleic acid isomers including cis-9, trans-11 18:2; trans-9, cis-11 18:2; and trans-10, cis-12 18:2. Also, the interaction increased milk concentration of polyunsaturated fatty acids. Monensin and SBO linearly reduced, with no significant interaction, milk concentration (g/100 g of FA) of short- and medium-chain fatty acids (<C16). Soybean oil reduced total saturated FA and increased total monounsaturated FA. These results suggest that monensin reduces milk fat percentage and this effect is accentuated when SBO is added to the ration.
Key Words: dairy cow • monensin • soybean oil • milk fat percentage
This article has been cited by other articles:
|
|
 |
|
  C. Benchaar and P. Y. Chouinard Short communication: Assessment of the potential of cinnamaldehyde, condensed tannins, and saponins to modify milk fatty acid composition of dairy cows J Dairy Sci, July 1, 2009; 92(7): 3392 - 3396. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
O. AlZahal, M. M. Or-Rashid, S. L. Greenwood, M. S. Douglas, and B. W. McBride The effect of dietary fiber level on milk fat concentration and fatty acid profile of cows fed diets containing low levels of polyunsaturated fatty acids J Dairy Sci, March 1, 2009; 92(3): 1108 - 1116. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. R. Osborne, N. E. Odongo, J. P. Cant, K. C. Swanson, and B. W. McBride Effects of supplementing glycerol and soybean oil in drinking water on feed and water intake, energy balance, and production performance of periparturient dairy cows J Dairy Sci, February 1, 2009; 92(2): 698 - 707. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Dubuc, D. DuTremblay, M. Brodeur, T. Duffield, R. Bagg, J. Baril, and L. DesCoteaux A randomized herd-level field study of dietary interactions with monensin on milk fat percentage in dairy cows J Dairy Sci, February 1, 2009; 92(2): 777 - 781. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. F. Duffield, A. R. Rabiee, and I. J. Lean A Meta-Analysis of the Impact of Monensin in Lactating Dairy Cattle. Part 2. Production Effects J Dairy Sci, April 1, 2008; 91(4): 1347 - 1360. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
