Response of Lactating Cows to 300 mg of Supplemental Vitamin E Daily

Abstract

Ten Holstein cows in mid-lactation which had been fed only stored feeds for several years were paired on milk production. One cow from each pair was assigned to either the control or group treated with supplemental vitamin E for a 12-wk experiment. All cows were fed 3 kg alfalfa-brome hay, corn silage ad libitum, and concentrate at 1 kg/3 kg milk produced daily. This ration provided about 500 mg of vitamin E (total tocopherols) daily. Five cows were fed an additional 300 mg vitamin E daily as D-alpha-tocopherol acetate in their concentrate mix. Feeding the supplemental vitamin E increased the vitamin E content of milk fat 15 to 20% from 18 microgram/g fat to over 21 microgram/g fat. However, this change in vitamin E content of milk was not sufficient to improve the oxidative stability of the milk. Blood characteristics indicative of vitamin E status generally were unaffected by vitamin E supplementation although red cell hemolysis, glutamic oxaloacetic transaminase, and lactate dehydrogenase of serum were lower in blood of supplemented cows.

Influence of feeding different types of roughage on the oxidative stability of milk

“…Moreover, numerous studies have shown that antioxidants as tocopherols and carotenoids can be transferred from the feed to the milk and thereby improve the oxidative stability of milk (Barrefors, Granelli, Appelqvist, & Bjoerck, 1995;Focant et al, 1998;Granelli, Barrefors, Bjoerck, & Appelqvist, 1998). Other studies have shown no effect of supplementing the diet with vitamin E (Schingoethe, Parsons, Ludens, Schaffer, & Shave, 1979;Charmley & Nicholson, 1995).…”

The difference in transfer of all-rac-α-tocopherol stereo-isomers to milk from cows and the effect on its oxidative stability

“…Furthermore, in an earlier study by Schingoethe et al (1979), it was shown that a-tocopherol in the feed is progressively oxidized during storage of the feed, leading to inadequate a-tocopherol intake by the cows especially during winter and spring months. Synthetic a-tocopherols called all-rac-a-tocopherol (IUPAC-IUB, 1982) show varying isomeric distribution, and some preparations are composed of equal parts of the eight stereo-isomers RRR, RRS, RSR, RSS, SSS, SSR, SRS, and SRR.…”

“…The most important lipid-soluble chain-braking antioxidant found in milk has been identified as a-tocopherol, also known as vitamin E (Dunkley et al, 1967;Niki, Yamamoto, Takahashi, Komuro, & Miyama, 1989;Schingoethe et al, 1979), and it is believed to act as a physical or chemical quencher of singlet oxygen (Gorman, Gould, Hamblett, & Standen, 1984). Several studies of spontaneous oxidized flavour in milk have shown that a low level of a-tocopherol in the feed is critical for the oxidative stability of the raw milk (Charmley, Nicholson, & Butler, 1991;Krukovsky, Whiting, & Loosli, 1950;Schingoethe, Parsons, Ludens, Tucker, & Shave, 1978;Schingoethe et al, 1979;St-Laurent, Hidiroglou, Snoddon, & Nicholson, 1990).…”

“…Several studies of spontaneous oxidized flavour in milk have shown that a low level of a-tocopherol in the feed is critical for the oxidative stability of the raw milk (Charmley, Nicholson, & Butler, 1991;Krukovsky, Whiting, & Loosli, 1950;Schingoethe, Parsons, Ludens, Tucker, & Shave, 1978;Schingoethe et al, 1979;St-Laurent, Hidiroglou, Snoddon, & Nicholson, 1990).…”

“…Oxidized flavour, a major defect in milk and other dairy products, is caused by volatiles produced by oxidative cleavage of the unsaturated fatty acids present in phospholipids and triglycerides (Dunkley, Ronning, Franke, & Robb, 1967;Schingoethe, Parsons, Ludens, Schaffer, & Shave, 1979). The oxidative stability of milk is also affected by the balance between pro-and anti-oxidative factors such as the content of transition metal ions, the content of lowmolecular anti-oxidants, and the relative activity of proand anti-oxidative enzymes (Nielsen, Østdal, & Andersen, 2002).…”