HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Interpretive Summary Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Al-Mabruk, R. M. Articles by Dewhurst, R. J. Search for Related Content PubMed PubMed Citation Articles by Al-Mabruk, R. M. Articles by Dewhurst, R. J.

Effects of Silage Species and Supplemental Vitamin E on the Oxidative Stability of Milk

¹ Institute of Rural Studies, University of Wales, Aberystwyth SY23 3AL, U.K.
² Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth SY23 3EB, UK

Corresponding author: R. J. Dewhurst, e-mail: richard.dewhurst{at}bbsrc.ac.uk.

Two experiments were conducted to study the effects of feeding legume silages and providing supplemental vitamin E in concentrates on the oxidative stability of milk. In experiment 1, six multiparous Holstein-Friesian cows were offered 1 of 6 silage treatments in a cyclical changeover-design experiment, with four 4-wk periods. The silages were grass, red clover, white clover, alfalfa, grass and red clover mixture (50:50 on a DM basis), and grass and white clover mixture (50:50 on a DM basis). In experiment 2, 8 cows were used in a changeover-design experiment with three 4-wk periods. The 4 treatments were a factorial combination of forages (grass silage or red clover silage) and supplemental vitamin E in the form of all-rac--tocopheryl acetate (29 or 290 IU/kg of DM in the concentrate). All forages were offered ad libitum and a flat rate of concentrates (8 kg/d) was fed in both experiments. Red clover silage led to significantly higher forage intakes, milk yields, and milk protein percentage in experiment 2, which was in agreement with results from experiment 1. There was no effect of vitamin E on feed intake, milk production, or milk fat and protein percentage. Red clover silage also led to significant changes in milk fatty acid profiles, particularly increased levels of polyunsaturated fatty acids. Milk samples were stored at 4°C and 20°C and analyzed for -tocopherol and thiobarbituric acid reactive substances at intervals to determine oxidative stability. Diets based on red clover and alfalfa silages were associated with more rapid loss of -tocopherol and increased production of thiobarbituric acid reactive substances during the storage of milk in comparison with diets based on grass silage. The increased oxidative deterioration of milk produced from cows fed red clover silage was avoided by vitamin E supplementation.

Key Words: legume silage • milk oxidation • red clover • vitamin E

Abbreviation key: AS = alfalfa silage, GRCS = mixture of grass silage and red clover silage (50:50 on a DM basis), GWCS = mixture of grass silage and white clover silage (50:50 on a DM basis), GS = grass silage, GS+ = grass silage + supplemental vitamin E, PUFA = polyunsaturated fatty acids, RCS = red clover silage, RCS+ = red clover silage + supplemental vitamin E, TBARS = thiobarbituric acid reactive substances, WCS = white clover silage

This article has been cited by other articles:

				J. A. Voelker Linton and M. S. Allen Nutrient Demand Interacts with Forage Family to Affect Intake and Digestion Responses in Dairy Cows J Dairy Sci, July 1, 2008; 91(7): 2694 - 2701. [Abstract] [Full Text] [PDF]

				J. D. Quigley, T. A. Wolfe, and T. H. Elsasser Effects of Additional Milk Replacer Feeding on Calf Health, Growth, and Selected Blood Metabolites in Calves J Dairy Sci, January 1, 2006; 89(1): 207 - 216. [Abstract] [Full Text] [PDF]