JDS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Journal of Dairy Science Vol. 74 No. 8 2573-2579
© 1991 by American Dairy Science Association ®
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Knapp, D. M.
Right arrow Articles by Grummer, R. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Knapp, D. M.
Right arrow Articles by Grummer, R. R.

Response of Lactating Dairy Cows to Fat Supplementation During Heat Stress

D. M. Knapp 1 and Ric R. Grummer 1

1 Department of Dairy Science, University of Wisconsin, Madison 53706

Effects of supplemental prilled long-chain fatty acids on lactation performance during heat stress were examined using eight multiparous Holstein cows in a replicated 4 x 4 Latin square design with 15-d periods. Cows were ruminally cannulated and were assigned randomly to one of four treatments in a 2 x 2 factorial arrangement of treatments. Factors were 0 or 5% supplemental fat and thermoneutral or heat stress conditions. Cows were housed in environmental chambers with thermoneutral conditions of 20.5°C and 38% relative humidity for 24 h/d or heat stress conditions of 31.8°C and 56% relative humidity for 14 h/d and 25.9°C with 56% relative humidity for 10 h/d. Isonitrogenous diets (17% CP) containing 50% alfalfa silage and 50% concentrate were offered for ad libitum intake. Diets contained 1.64 or 1.83 Mcal NEL/kg DM. No diet by environment interactions were significant. Milk fat percentage (3.46 vs. 3.15%) and 3.5% FCM (31.5 vs. 29.2 kg/d) were higher for cows fed 5 vs. 0% fat. Dry matter intake, milk yield, and milk protein percentage did not differ between diets. Heat stress decreased DMI, milk yield, 3.5% FCM, and milk protein percentage but did not affect milk fat percentage. Results suggest that supplemental fat at 5% of diet DM enhances lactation performance similarly under thermoneutral and heat stress conditions.

Key Words: supplemental fat • heat stress • lactating cows

Submitted on December 17, 1990
Accepted on March 1, 1991




This article has been cited by other articles:


Home page
 J DAIRY SCIHome page
C. E. Moore, J. K. Kay, R. J. Collier, M. J. VanBaale, and L. H. Baumgard
Effect of Supplemental Conjugated Linoleic Acids on Heat-Stressed Brown Swiss and Holstein Cows
J Dairy Sci, May 1, 2005; 88(5): 1732 - 1740.
[Abstract] [Full Text] [PDF]

Home page
 J DAIRY SCIHome page
A. Arieli, G. Adin, and I. Bruckental
The Effect of Protein Intake on Performance of Cows in Hot Environmental Temperatures
J Dairy Sci, March 1, 2004; 87(3): 620 - 629.
[Abstract] [Full Text] [PDF]

Home page
 J DAIRY SCIHome page
N. R. St-Pierre, B. Cobanov, and G. Schnitkey
Economic Losses from Heat Stress by US Livestock Industries
J Dairy Sci, July 1, 2003; 86(13_suppl): E52 - 77.
[Abstract] [Full Text] [PDF]

Home page
 J DAIRY SCIHome page
J. K. Drackley, T. M. Cicela, and D. W. LaCount
Responses of Primiparous and Multiparous Holstein Cows to Additional Energy from Fat or Concentrate During Summer
J Dairy Sci, April 1, 2003; 86(4): 1306 - 1314.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1991 by the American Dairy Science Association ®.