|
|
||||||||
1 University of Maryland, College Park 20742
2 USDA, Agricultural Research Service, Beltsville, MD 20705
This experiment determined the effects of infusion of mixtures of fat containing predominantly cis-C18:1 or trans-C18:1 fatty acids into the abomasum on responses of cows to glucose and norepinephrine challenges administered i.v. Six lactating Holstein cows, each with a rumen cannula, were arranged in two Latin squares with 21-d periods. The common basal diet contained 40% forage and 60% concentrate. Treatments were the uninfused control, 750 g/d of a cis fat mixture (65% high oleic sunflower oil and 35% cocoa butter), and 750 g/d of a trans fat mixture (93% shortening and 7% corn oil) infused into the abomasum via a tube that passed through the rumen cannula. Glucose challenges (0.4 mg/kg of BW, administered i.v.) were conducted on d 18, and norepinephrine challenges (0.7 µg/kg of BW, administered i.v.) were conducted on d 19 of each experimental period. Despite a lower percentage of fat in milk for trans than for cis treatment, disappearance rates of glucose, secretion of insulin after glucose challenge, and appearance rates of NEFA and triglycerides after norepinephrine challenge were similar between treatments. Thus, these data support the hypothesis that trans-C18:1 fatty acids affect the synthesis of milk fat in the mammary gland of lactating cows.
Key Words: glucose norepinephrine trans-C18:1 fatty acids milk fat depression
Submitted on October 4, 1995
Accepted on April 8, 1996
This article has been cited by other articles:
![]() |
A. E. Brickner, J. A. A. Pires, T. F. Gressley, and R. R. Grummer Effects of abomasal lipid infusion on liver triglyceride accumulation and adipose lipolysis during fatty liver induction in dairy cows J Dairy Sci, October 1, 2009; 92(10): 4954 - 4961. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. A. Pires, J. B. Pescara, A. E. Brickner, N. Silva del Rio, A. P. Cunha, and R. R. Grummer Effects of Abomasal Infusion of Linseed Oil on Responses to Glucose and Insulin in Holstein Cows J Dairy Sci, April 1, 2008; 91(4): 1378 - 1390. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. R. Roche, A. J. Sheahan, L. M. Chagas, and R. C. Boston Short Communication: Change in Plasma Ghrelin in Dairy Cows Following an Intravenous Glucose Challenge J Dairy Sci, March 1, 2008; 91(3): 1005 - 1010. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. J. Harvatine and M. S. Allen Effects of Fatty Acid supplements on milk yield and energy balance of lactating dairy cows. J Dairy Sci, March 1, 2006; 89(3): 1081 - 1091. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. J. Bradford and M. S. Allen Milk Fat Responses to a Change in Diet Fermentability Vary by Production Level in Dairy Cattle J Dairy Sci, November 1, 2004; 87(11): 3800 - 3807. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |