| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Animal Science, Cornell University, Ithaca, NY 14853
2 Novus International, Inc., St. Louis, MO 63141
Corresponding author: T. R. Overton; e-mail: tro2{at}cornell.edu.
Forty-eight Holstein cows, entering second or later lactation, were utilized to determine the effects of 2-hydroxy-4-(methylthio)-butanoic acid (HMB) on milk production, hepatic lipid metabolism, and gluconeogenesis during the periparturient period. Cows were fed one of 3 diets as TMR starting 21 d before expected calving. These diets contained 0 (the basal diet), 0.09 (+HMB), or 0.18 (++HMB)% HMB. From parturition to 84 DIM, cows were fed diets that contained 0, 0.13, or 0.20% HMB. Prepartum and postpartum dry matter intakes were similar among cows fed the basal diet, +HMB and ++HMB. There was a quadratic effect on milk yield such that cows fed +HMB had the greatest milk yield; yields of milk by cows fed the basal diet and ++HMB were similar. This led to trends for increased yields of 3.5% fat-corrected milk and total solids when cows were fed +HMB. Percentages of fat, protein, and total solids in milk were not affected by treatment. Despite differences in milk yield, calculated energy balance was not affected by treatment. Plasma concentrations of NEFA, ß-hydroxybutyrate, and glucose were not different among treatments. Liver triglyceride content was similar among treatments on d 1 postpartum and was increased for cows consuming +HMB on d 21 postpartum compared with the other dietary treatments. Capacities for metabolism of [1-14C]palmitate by liver slices in vitro were not affected by treatment; however, conversion of [1-14C]propionate to CO2 and glucose decreased as the amount of HMB consumed by cows increased on d 21 postpartum. Cows consuming +HMB had greater days to first ovulation compared with cows consuming the basal diet and ++HMB as measured by plasma progesterone concentrations. These data suggest that adding HMB to low Met diets to achieve a predicted Met supply of approximately 2.3% of metabolizable protein supply is beneficial for increasing milk production but does not appear to benefit hepatic energy metabolism during early lactation.
Key Words: dairy cow • methionine • gluconeogenesis • hepatic lipidosis
Abbreviation key: HMB = 2-hydroxy-4-(methylthio)-butanoic acid, TG = triglyceride, VLDL = very low density lipoproteins
This article has been cited by other articles:
|
|
 |
|
  L. M. Johnson-VanWieringen, J. H. Harrison, D. Davidson, M. L. Swift, M. A. G. von Keyserlingk, M. Vazquez-Anon, D. Wright, and W. Chalupa Effects of Rumen-Undegradable Protein Sources and Supplemental 2-Hydroxy-4-(Methylthio)-Butanoic Acid and Lysine{middle dot}HCl on Lactation Performance in Dairy Cows J Dairy Sci, November 1, 2007; 90(11): 5176 - 5188. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. B. Carlson, N. B. Litherland, H. M. Dann, J. C. Woodworth, and J. K. Drackley Metabolic Effects of Abomasal L-Carnitine Infusion and Feed Restriction in Lactating Holstein Cows J Dairy Sci, December 1, 2006; 89(12): 4819 - 4834. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Rulquin, B. Graulet, L. Delaby, and J. C. Robert Effect of different forms of methionine on lactational performance of dairy cows. J Dairy Sci, November 1, 2006; 89(11): 4387 - 4394. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. R. Overton and M. R. Waldron Nutritional Management of Transition Dairy Cows: Strategies to Optimize Metabolic Health J Dairy Sci, July 1, 2004; 87(13_suppl): E105 - 119. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
