Plasma alpha-tocopherol profiles in sheep after oral administration of dl-alpha-tocopheryl acetate and d-alpha-tocopheryl polyethylene glycol-1000 succinate.

Twenty-five yearling wethers, weighing 45 to 50 kg, were used in a trial designed to compare the bioavailability of dl-alpha-tocopheryl acetate (TA) and d-alpha-tocopheryl polyethylene glycol-1000 succinate (TPGS). The sheep, five per treatment, were each given a basal diet without vitamin E supplement (control) or with a daily oral supplement of 240 iu TA or TPGS, or of 480 iu TA or TPGS. Blood samples were obtained at zero time, and then twice daily for three weeks. The bioavailability was greater for TA than for TPGS. This was indicated by the significantly higher (P less than 0.01) plasma alpha-tocopherol concentrations during the three-week experimental period in sheep dosed with equivalent units of TA than in those dosed with TPGS. When administered at 480 iu, the TPGS produced plasma profiles similar to those found after administration of the lower (240 iu) dose of the TA.     

Vitamin E requirement of mink with special reference to tocopherol composition in plasma, liver, and adipose tissue

Tissue responses of 4 different tocopherols found in a basal diet (BD) and the effect of 2 physiologic levels of dl-alpha-tocopheryl acetate (25 and 150 mg/kg) on tissue tocopherol content were studied in the mink. The BD contained a total of 7.1 mg vitamin E/kg, with alpha-, beta-, gamma-, and delta-tocopherol in a ratio of 1:0.07:0.55:0.10, respectively. The corresponding ratios in the tissues were: liver, 1:0.04:0.12:0; plasma, 1:0:0.13:0; and adipose tissue, 1:0:0.19:0. After mink were fed diets containing vitamin E, alpha- and gamma-tocopherol were distributed in similar proportions in plasma and liver, but gamma-tocopherol was in a slightly higher proportion in adipose tissue. Addition of 25 or 150 mg/kg of alpha-tocopheryl acetate to the BD decreased the gamma-tocopherol levels in all 3 tissues; this was considered to be a dilution effect of other tocopherols in BD with added alpha-tocopheryl acetate. The beta-tocopherol content in the liver remained unchanged, irrespective of the dietary amount of alpha-tocopheryl acetate. Plasma alpha-tocopherol had a linear relationship to log dietary dose, with an apparent half-saturation of the vitamin E binding capacity at 13 mg vitamin E/kg diet. At the given dietary levels, liver and adipose continued to accumulate alpha-tocopherol. The correlation between total plasma lipids and plasma alpha-tocopherol was significant (P less than 0.001) only in the group fed the BD. Vitamin E analysis of plasma could be used as a routine method for controlling the vitamin E status of mink.(ABSTRACT TRUNCATED AT 250 WORDS)     

Vitamin E supplementation can alleviate negative effects of heat stress on egg production,egg quality,digestibility of nutrients and egg yolk mineral concentrations of Japanese quails

The aim of this study was to determine if the negative effects of high ambient temperature (34 degrees C) on egg production, egg quality, digestibility of nutrients, and mineral content of egg yolk could be alleviated by dietary vitamin E (dl-alpha-tocopheryl acetate) supplementation in laying Japanese quails (Coturnix coturnix japanica). Japanese quails (n=240; 7-week-old) were divided into eight groups, 30 birds per group. The quails were fed either a basal diet or the basal diet supplemented with either 125, 250 or 500 mg of dl-alpha-tocopheryl acetate/kg of diet. Birds were kept at 22 degrees C and 55% relative humidity (RH). At 14 weeks of age, the thermo-neutral (TN) group remained in the same temperature as at the beginning of the experiment, whereas the heat stress (HS) group was kept at an environment-controlled room at 34 degrees C and 44% RH for 3 weeks. Heat exposure decreased performance when basal diet was fed (P=0.001). With 250 and 500 mg/kg of diet, an increase in body weight (P=0.01), feed intake (P=0.01), egg production (P=0.001), and improvement in feed efficiency (P=0.01) was found with vitamin E supplementation in quails reared under heat stress conditions (HS). Similarly, egg weight (P=0.01), egg specific gravity (P=0.01), egg shell thickness (P=0.05) and Haugh unit (P=0.01) were positively influenced by vitamin E supplementation. Heat exposure decreased digestibility of dry matter (DM) (P=0.03), organic matter (OM) (P=0.05), crude protein (CP) (P=0.02), ether extract (EE) (P=0.05) and were elevated by supplemental vitamin E (P相似文献   

Effect of vitamin E and fat source in sows' diets on immune response of suckling and weaned piglets

Thirty-six 7-mo-old gilts were used to study the effects of dietary vitamin E and fat source (5% sunflower oil or animal fat) in pregnant and lactating sow diets on serum vitamin E concentration and on cell-mediated and humoral immune response in suckling and weaned piglets. Six gilts each received one of six diets throughout pregnancy and lactation. The basal diets (13 mg alpha-tocopherol/kg diet) were supplemented with dl-alpha-tocopheryl acetate to 48 and 136 mg alpha-tocopherol/kg of feed (average analyzed values). After weaning (at 4 wk of age) all pigs received identical diets (20 mg of alpha-tocopherol/kg feed). One week after weaning, pigs were immunized (i.m. with ovalbumin and tetanus toxoid) and antibody production was measured. Blood samples were taken immediately after birth, at 1 wk after birth, at weaning, and at four weekly intervals after weaning. Samples were analyzed for alpha-tocopherol concentration, total number of leukocytes, T- and B-lymphocytes, lymphocyte stimulation with concanavalin A, lysozyme activity, and immunoglobulin concentrations. It was concluded that a high vitamin E level in the sow's diet increased serum vitamin E concentration of 1-wk-old pigs (P less than .05). Immune response against ovalbumin was increased (P less than .05) at 1 wk of age after immunization for weaned pigs from sows fed the high level of vitamin E. Also, the phagocytic measures of pigs at 1 wk of age were increased by the medium vitamin E level (P less than .05). Fat sources in the sow's diet had no consistent effect on the immunological measures of pigs.     

Influence of dietary rapeseed oil, vitamin E, and copper on the performance and the antioxidative and oxidative status of pigs.

We investigated the effects of dietary copper and vitamin E in diets containing 6% rapeseed oil on the performance and the antioxidative and oxidative status of growing pigs. The 10 dietary treatments consisted of a basal diet (9 mg of vitamin E/kg feed, 15 mg of Cu/kg feed), the basal diet + 6% rapeseed oil (Diet 1; 18 mg of vitamin E/kg feed, 15 mg of Cu/kg feed), and Diet 1 plus supplements of vitamin E (0, 100, and 200 mg of dl-alpha-tocopheryl acetate/kg feed) and copper (0, 35, and 175 mg of Cu/ kg feed) in a 3 x 3 factorial arrangement of treatments. Eight or nine pigs were given ad libitum access to each diet from 25 to 100 kg of live weight. The inclusion of rapeseed oil tended (P < .10) to improve ADG and feed utilization. Compared with the addition of 35 mg of Cu/kg, the addition of 175 mg/kg improved growth rate and increased feed intake early in the experiment, but, over the total experiment, neither 35 nor 175 mg of Cu/kg affected performance. Compared with the addition of 100 mg of vitamin E/kg or no addition, the addition of 200 mg/kg reduced ADG over the total experiment (P = .05). The antioxidative and oxidative status of the pigs was evaluated in terms of blood and liver concentrations of antioxidants (alpha-tocopherol, ascorbic acid, vitamin A, superoxide dismutase, glutathione peroxidase), prooxidants (Cu), concentrations of lipids (triglycerides and cholesterol), fatty acid composition, thiobarbituric acid-reactive substances (TBARS), and clinical chemical (creatine kinase and glutamate-oxaloacetate-transaminase) and hematological variables that indicate the level of oxidative stress. There were no vitamin E deficiency signs or increased oxidative stress in pigs fed low dietary vitamin E levels, and no prooxidative effect of Cu was found. Increasing dietary levels of vitamin E increased the concentration of alpha-tocopherol in plasma and liver. Supplementation with Cu increased liver concentrations of Cu and alphatocopherol. The progression in liver TBARS was reduced by the addition of vitamin E and Cu. The addition of rapeseed oil changed the fatty acid composition of liver, increased alpha-tocopherol concentration in plasma and Cu concentration in liver, and reduced the rate of lipid oxidation in liver. In conclusion, even though the effects were minor, vitamin E, Cu, and rapeseed oil improved the antioxidative status of the live pigs.     

Effect of dietary levels of vitamin E (all-rac-tocopheryl acetate) with or without added fat on weanling pig performance and tissue alpha-tocopherol concentration

Two experiments involving 496 cross-bred pigs evaluated the efficacy of various dietary levels of vitamin E, with or without supplemental fat, on postweaning pig performance and weekly serum and terminal tissue alpha-tocopherol concentrations. The first trial involved 248 pigs weaned at an average of 15 d of age and 4.8 kg BW. The experiment was a randomized complete block design conducted in seven replicates. Vitamin E was added as dl-alpha-tocopheryl acetate at 0, 20, 40, 60, 80, 100, 150, or 200 IU/kg diet. Pigs were bled initially and at 7-d intervals for a 42-d period. Liver and s.c. adipose tissue samples were collected from six pigs per treatment group at 42 d. In Exp. 2, a 2 x 4 factorial arrangement of treatments in a randomized complete block design was conducted in seven replicates. The experiment used a total of 248 pigs weaned at 19 d of age and averaged 6.4 kg BW. Four vitamin E levels (0, 20, 40, and 60 IU/kg diet) and two added fat levels of 0 or 5% were fed for 35 d. Four pigs per treatment pen were bled weekly, and at 35 d a total of four pigs per treatment group were killed and liver, heart, and s.c. adipose tissues were collected and analyzed for alpha-tocopherol. The basal diet in both experiments contained an average 7.9 IU for period 1, and later diets averaged 11.0 IU vitamin E/kg. In both experiments serum alpha-tocopherol concentrations declined from weaning to 7 d after weaning and continued to decline each week after weaning when the basal diets were fed. Serum alpha-tocopherol concentrations increased (P < 0.01) each week as the dietary vitamin E level increased in both experiments. In Exp. 2, when fat was added to the diet serum alpha-tocopherol concentrations were higher (P < 0.01) than in diets without added fat. Liver, heart muscle, and adipose tissue alpha-tocopherol concentrations increased (P < 0.01) as vitamin E level increased, but at the higher dietary vitamin E level the liver surpassed the adipose tissue in its alpha-tocopherol concentration. Liver and adipose alpha-tocopherol concentrations were higher (P < 0.01) when fat was added to the diet. These results indicate that supplementation of 40 to 60 IU/kg diet with added fat resulted in a relatively constant balance of serum and tissue concentration of alpha-tocopherol during the nursery period, but when fat was not supplemented a dietary vitamin E level of 80 to 100 IU/kg diet may be needed. The current NRC recommendations for vitamin E for the pig from 5 to 20 kg BW may need to be reevaluated.     

Influence of high vitamin E dosages on retinol and carotinoid concentration in body tissues and eggs of laying hens.

The aim of the study was to contribute to the discussion of overdosing vitamin E in laying hens. A total of 45 laying hens, divided into 5 groups were fed diets supplemented with either 0; 100; 1000; 10,000 or 20,000 mg dl-alpha-tocopheryl acetate/kg diet over a period of 10 weeks. Concentrations of vitamins A and E were measured in plasma, various tissues and egg yolk. Furthermore egg yolk colour and some carotinoids were measured in egg yolks. None of the vitamin E doses significantly influenced performance of the hens. As expected, vitamin E concentration in plasma, all tissue samples and egg yolk was significantly increased with increasing tocopherol content in the diet. The egg yolk showed the highest vitamin E concentration, followed by liver and muscles. Feeding 1000 mg alpha-tocopheryl acetate per kg diet resulted in an increase of vitamin A concentration in the liver. Very high doses (10,000 and 20,000 mg/kg diet) significantly decreased retinol concentration in the liver and egg yolk, as well as carotinoid concentration in the egg yolk. The lower carotinoid concentration in egg yolk resulted in a decreased intensity of egg yolk colour. A prooxidative and/or competitive effect of very high doses of vitamin E with other fat soluble substances has been discussed.     

Antioxidative and oxidative status in muscles of pigs fed rapeseed oil, vitamin E, and copper

The susceptibility of a given muscle tissue to lipid oxidation may not only depend on the presence of unsaturated fatty acids and the balance between antioxidants and prooxidants, but also on the composition of the skeletal muscle. In the present study, the effects of dietary supplementation of vitamin E (dl-alpha-tocopheryl acetate) and copper in combination with a high level of monounsaturated fatty acids were examined with regard to the antioxidant concentration and the susceptibility to lipid oxidation of two muscles, longissimus (LD) and psoas major (PM), representing different oxidative capacity. In addition, fatty acid profiles of the backfat and the intramuscular lipids, as well as fresh meat quality traits, were studied. Pigs were allotted to a 3x3 factorial experiment with three levels of dl-alpha-tocopheryl acetate (0, 100, and 200 mg/kg of feed) and three levels of copper (0, 35, and 175 mg/kg of feed) added to a diet containing 6% rapeseed oil. A basal diet (without rapeseed oil) was added to the experimental design, giving a total of 10 dietary treatments. Muscle alpha-tocopherol concentrations increased (P<.001) with increasing dl-alpha-tocopheryl acetate in the feed. The antioxidative status was higher in PM than in LD, when considering the concentration of alpha-tocopherol (P<.001) and the activity of antioxidant enzymes (superoxide dismutase, P<.001; glutathione peroxidase, P = .06). Supplemental copper did not give rise to any deposition of copper in muscle tissue or backfat, but the antioxidant status of PM increased. The susceptibility to lipid oxidation was reduced in LD with increasing dietary dl-alpha-tocopheryl acetate and in PM with increasing dietary copper. Supplemental dl-alpha-tocopherol acetate improved the water-holding capacity of LD (P = .005) and PM (P = .003). The fatty acid composition of the backfat and the triglyceride fraction of the intramuscular fat became more unsaturated with the addition of rapeseed oil to the feed. Higher intakes of monounsaturated fatty acids due to the rapeseed oil were also reflected in the phospholipid fraction of the intramuscular fat, but no influence on the proportion of saturated fatty acids was seen. The susceptibility to lipid oxidation of PM was lower for pigs on the rapeseed oil-based diet than for those on the basal diet. The energy metabolic status of the muscles and the accumulation of calcium by the sarcoplasmic reticulum were not influenced by the dietary treatments, but there were differences between muscle types. The addition of rapeseed oil to the diet reduced the muscular content of glycogen (LD, P = .02; PM, P = .06) and elevated the plasma concentration of free fatty acids (P = .05). Overall, dietary fat, dl-alpha-tocopherol acetate, and copper affected the oxidative status of pig muscles, and the results differed depending on muscle type.     

Vitamin E status in newborn lambs with special reference to the effect of dl-alpha-tocopheryl acetate supplementation in late gestation

Pregnant ewes were supplemented with dl-alpha-tocopheryl acetate, either as a single intramuscular dose (500 mg two weeks before lambing) or perorally (150 mg daily during 3-4 weeks before lambing). Ewes without such a supplementation were controls. The vitamin E supplemented ewes had nearly twice as high vitamin E (alpha-tocopherol) concentrations as the unsupplemented control ewes at lambing both in serum and in colostrum. The vitamin E concentration in colostrum was 5-11 higher than in milk 1 week after lambing. Both supplementations somewhat increased the vitamin E serum concentration of the newborn lambs, but the increase was negligible in comparison with the effect produced by the consumption of colostrum. All lambs had very low serum concentrations at birth. The lambs from the supplemented ewes had significantly higher serum values than the control lambs 24 h after birth. The ewes had somewhat higher selenium status at birth than their offsprings when evaluated by glutathione peroxidase (GSH-Px) in the erythrocytes. It seems reasonable that nutritional muscular degeneration may arise in newborn lambs with a normal selenium status if their vitamin E status is critical, either because of an inadequate consumption of colostrum or because of a vitamin E deficient diet during pregnancy with a low vitamin concentration of colostrum as a consequence.     

Vitamin E concentrations in blood plasma of sheep and in sheep tissues after a single intraruminal or intraperitoneal administration of DL-alpha-tocopheryl acetate

Twenty-five yearling wethers, weighing 40 to 45 kg were used in a trial designed to compare the effect of the route of administration of vitamin E upon plasma and tissue vitamin E status. Five control sheep without vitamin E administration were killed at the beginning of the trial. Of the remaining 20 sheep, 10 were given DL-alpha-tocopheryl acetate intraruminally and 10 by intraperitoneal injection. Of these, 10 wethers were killed three days after dosing (five from each treatment, IR3 and IP3) and the remaining wethers were killed eight days after dosing (IR8 and IP8). Blood samples were taken throughout the trial from sheep on the IR8 and IP8 treatments. Samples of whole adrenal gland, heart, liver, kidney, brachiocephalicus muscle, lung, pancreas and spleen were taken from all sheep at slaughter and were analysed for their vitamin E content. The blood plasma results showed that the most important index of vitamin E bioavailability, the area under the plasma concentration versus time curve, was greater in the intraperitoneally than intraruminally dosed sheep. There was a higher concentration of vitamin E in the tissues from the intraperitoneal group than the intraruminal group three days after the intraperitoneal injections. The results suggest that the greatest responses in vitamin E concentration in plasma and the tissues were recorded in sheep following intraperitoneal rather than intraruminal dosing with DL-alpha-tocopheryl acetate.     

Effect of alpha-tocopheryl acetate supplementation on vitamin E concentrations in Greyhounds before and after a race.

OBJECTIVES: To determine effect of alpha-tocopherol supplementation on serum vitamin E concentrations in Greyhounds before and after a race. ANIMALS: 8 adult racing Greyhounds. PROCEDURE: Dogs were given 2 capsules of alpha-tocopheryl acetate (total, 680 units [0.5 g]) with food that contained < or = 15 mg of vitamin E/kg each morning for 7 days. Dogs were exercised in a 30 X 30-m grass paddock for 15 minutes twice a day and raced for 500 m twice a week. Blood samples were collected before and 5 minutes after a race, before supplementation was begun, and after 7 days of supplementation. Blood and diet samples were analyzed for tocopherols and alpha-tocopheryl acetate. RESULTS: Before supplementation, serum alpha-tocopherol concentration after racing (mean +/- SD, 6.7 +/- 2.4 mg/L ) was significantly lower than before racing (12.2 +/- 3.1 mg/L). After supplementation, alpha-tocopherol concentrations were significantly higher overall, although values obtained before (26.6 +/- 5.2 mg/L) and after (29.8 +/- 3.6 mg/L) racing were not significantly different. CONCLUSIONS AND CLINICAL RELEVANCE: Supplementation with alpha-tocopheryl acetate increased serum alpha-tocopherol concentrations and eliminated the decrease in alpha-tocopherol concentration that was detected after a race, which may decrease oxidation during exercise and improve performance or recovery.     

Optimal dietary concentration of vitamin E for alleviating the effect of heat stress on egg production in laying hens.

1. The effects of different dietary concentrations of vitamin E (alpha-tocopherol acetate) were investigated on laying hens exposed to chronic heat stress at 32 degrees C from 26 to 30 weeks of age. 2. Diets containing 5 dietary concentrations of vitamin E (a control diet containing 10 mg alpha-tocopherol/kg or this diet supplemented to contain 125, 250, 375 and 500 mg alpha-tocopherol/kg) were fed to 335 birds. Half of the birds received the supplemented diets for only 4 weeks before the heat stress period (short supplementation duration, SSD) and were fed on the control diet for a further 12 weeks. The remaining birds were fed on the supplemented diets throughout the experiment, 4 weeks before, 4 weeks during and 8 weeks after the heat stress period (long supplementation duration, LSD). 3. Egg production was significantly higher during (80-6 vs 68.9%, P<0.02) and after (75.3 vs 62.7%, P<0.02) the period of stress in the LSD group fed on the diet containing 250 mg vitamin E/kg compared with the group fed on the control diet. LSD birds given 375 and 500 mg vitamin E/kg also had higher egg production than control birds during heat stress but the differences failed to reach significance (74.6 vs 68.9% and 77.1 vs 68.9% respectively). In the SSD groups, mean egg production of the birds given the diets supplemented with 125 mg vitamin E/kg or more was significantly different from the control group after heat stress (70.3 vs 62.7%, P<0.05). Egg weight and food intake were similar in all the groups. 4. Plasma and liver vitamin E concentrations were proportional to the vitamin E intake before the stress period, dropped during heat stress in the SSD groups but were maintained at concentrations closer to those observed before heat stress in the LSD groups. 5. It is concluded that a dietary supplement of 250 mg vitamin E/kg provided before, during and after heat stress is optimum for alleviating, at least in part, the adverse effects of chronic heat stress in laying hens.     

An evaluation of natural (RRR-alpha-tocopheryl acetate) and synthetic (all-rac-alpha-tocopheryl acetate) vitamin E fortification in the diet or drinking water of weanling pigs

Three experiments conducted with weanling pigs evaluated the effects of vitamin E added to the drinking water or diet on plasma and tissue alpha-tocopherol concentrations. When natural or synthetic vitamin E was used, it was added at an IU-equivalent basis, but natural vitamin E was 73.5% (mg basis) of the synthetic vitamin E. Experiment 1 used 18-d-old weanling pigs (n = 120) in a 3 x 2 factorial arrangement of treatments in a randomized complete block design with 4 replicates. The first factor evaluated the dietary levels of natural vitamin E (RRR-alpha-tocopheryl acetate) added at 0, 50, or 300 IU/kg, whereas the second factor was the natural vitamin E added to the drinking water at 0 or 100 IU/L. Pigs were bled at periodic intervals, and 1 pig per pen was killed at the end of the 21-d trial and tissues (liver, heart, lung, and loin) were collected for alpha-tocopherol analysis. When vitamin E was not added to the diet or water, plasma alpha-tocopherol declined over the 21-d period. Although there were some interactions (P < 0.01), tissue and plasma alpha-tocopherol concentrations increased linearly when vitamin E was added to the diet or water. Experiment 2 was a 3 x 2 factorial in a randomized complete block design with 4 replicates. A total of 96 pigs weaned at 18 d of age, with an initial BW of 6.2 kg, were fed a nonvitamin E fortified diet, but natural or synthetic (all-rac-alpha-tocopheryl acetate) vitamin E was added to their drinking water at 50, 100, or 150 IU/L. Pigs were bled at 0, 3, 7, 10, 14, and 21 d postweaning, with tissues (liver, lung, heart, and loin) collected for alpha-tocopherol analysis at d 21. The results indicated that plasma alpha-tocopherol concentrations increased (P < 0.01) as vitamin E increased, with greater tissue alpha-tocopherol concentrations (P < 0.01) when natural vitamin E was provided. Experiment 3 was conducted in 2 replicates, but pigs (n = 60) were not provided vitamin E in the diet or water for 7 d postweaning, and then natural or synthetic vitamin E was added to the drinking water as in Exp. 2 (50, 100, or 150 IU/L). Pigs were bled at 0, 2, 4, 6, 8, 10, and 24 h after being provided vitamin E to evaluate the absorption from each vitamin E source and level. Plasma alpha-tocopherol increased quadratically (P < 0.01) and plateaued at 8 to 10 h for each treatment group. These results indicate that adding vitamin E to the pig's water supply at weaning was more effective in increasing plasma alpha-tocopherol than when it was added to the diet during the initial 14 d postweaning, and that natural vitamin E was a superior source compared with synthetic vitamin E.     

Effect of high concentrations of dietary vitamin E during various age periods on performance, plasma vitamin E and meat stability of broiler chicks at 7 weeks of age.

1. The effect of high concentrations of vitamin E (alpha-tocopheryl acetate) fed during various age periods on the performance and the oxidative stability (thiobarbituric acid [TBA] values) of the drumstick meat of 7-week-old broiler chicks was determined. The basal diets (for the age periods 0 to 3, 3 to 6 and 6 to 7 weeks) contained 60 g soyabean oil and 24 mg vitamin E/kg. The following five treatments were evaluated: (1) the basal diets from 0 to 7 weeks of age (control); (2) vitamin E, 100 mg/kg diet from 0 to 7 weeks of age; (3) vitamin E, 150 mg/kg diet from 0 to 3 weeks of age; (4) vitamin E, 150 mg/kg diet from 0 to 3 weeks of age and 100 mg/kg diet from 6 to 7 weeks of age; (5) vitamin E, 100 mg/kg diet from 5 to 7 weeks of age. 2. Food intake, weight gain and food efficiency were not significantly (P greater than 0.05) affected by the vitamin E treatments. 3. Plasma alpha-tocopherol (AT) concentrations in treatments 2, 4 and 5 were similar, and markedly higher than those in treatments 1 and 3, while those of treatment 3 were significantly (P less than 0.001) higher than those of treatment 1. Plasma retinol concentrations were not significantly (P greater than 0.05) affected by the vitamin E treatments. 4. TBA values of the meat were very low and not significantly affected by the vitamin E treatments. However, after incubation the TBA values were highly significantly (P less than 0.01) negatively correlated with the amount of vitamin E consumed during the experiment. The stability of meat of birds fed the various combinations of vitamin E (treatments 3, 4 and 5) was significantly (P less than 0.05) higher than that of birds which did not receive additional vitamin E (treatment 1), but it was significantly (P less than 0.001) lower than that of birds which received vitamin E continuously (treatment 2). 5. It is concluded that a high concentration of vitamin E fed during 0 to 3 weeks of age may significantly improve AT status of the broiler chick up to 7 weeks of age.     

Vitamin E requirements of adult Standardbred horses evaluated by tissue depletion and repletion

Vitamin E requirements of adult Standardbred horses were evaluated by tissue depletion and repletion. All the horses used in the study were given the same basal feed low in vitamin E during the eight months of the experiment. After an initial depletion period of two-and-a-half months the horses were divided into groups according to the amounts of DL alpha-tocopheryl acetate given (0 mg, control; 200, 600, 1800 and 5400 mg, respectively) as a daily oral supplement. The supplement study was followed by a second depletion period. Total vitamin E content and individual natural tocopherol isomers and tocotrienol isomers were measured both in the feed (hay and oats) and in tissue (serum, liver, skeletal muscle and adipose tissue) using high performance liquid chromatography with fluorescent detection. Tissue vitamin E response to different dietary vitamin E levels were studied. The serum total lipid content remained unchanged during the experiment; serum vitamin E levels were expressed per gram serum lipid. The total vitamin E levels in serum, liver, skeletal muscle and fat reflected the supplement levels. The highest vitamin E levels were seen in fat tissue, followed by the liver and by skeletal muscle. In spite of the wide occurrence of the different vitamin E isomers in the feed, alpha-tocopherol was almost the only isomer detected in the tissues. To ensure nutritional adequacy, 600 and 1800 mg of DL alpha-tocopheryl acetate was suggested as an optimal oral daily supplement of vitamin E to adult Standardbred horses given feed low in vitamin E; this corresponds to 1.5 to 4.4 mg/kg bodyweight.(ABSTRACT TRUNCATED AT 250 WORDS)     

alpha-Tocopherol concentrations in serum and tissues of sheep fed different sources of vitamin E.

Thirty-five crossbred wethers were used to determine the concentrations of alpha-tocopherol in serum and tissues after oral supplementation of six different vitamin E product forms. Five wethers were assigned to each of the following treatments: 1) control, no supplemental vitamin E (C), 2) emulsifiable DL-alpha-tocopheryl acetate-dry (Rovimix E-50% SD), 3) nonemulsifiable DL-alpha-tocopheryl acetate-dry (Rovimix E-50% Ads), 4) emulsifiable DL-alpha-tocopheryl acetate-liquid (Rovimix E-40% Dispersible Liquid Concentrate [DLC]); 5) emulsifiable DL-alpha-tocopherol-liquid (Hoffmann-La Roche, E-40% DLC alcohol), 6) micellized DL-alpha-tocopheryl acetate-liquid (Bioglan, Inc., E-20%); and 7) micellized DL-alpha-tocopherol-liquid (Bioglan, Inc., E-20%). Animals were supplemented daily with 1,000 IU of their respective vitamin E sources for 56 d. Blood samples were collected daily from d 0 to 7 and weekly until d 56. Animals were subsequently killed by exsanguination after stunning and eight different tissues were collected for alpha-tocopherol analysis. There were effects of day, treatment, and day x treatment interaction on serum alpha-tocopherol. All supplemented groups were higher in serum alpha-tocopherol concentration than were the C wethers. The emulsifiable vitamin E alcohol liquid product form (Treatment 5) yielded higher (P less than .01) serum alpha-tocopherol concentration than the emulsifiable acetate liquid product (Treatment 4). Sheep on Treatment 5 reached maximum concentration on d 1, sheep on Treatment 6 on d 2, and the sheep on the remaining Treatments by d 3. Blood sera alpha-tocopherol concentrations stabilized by d 6 in all supplemented groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of dietary oregano oil and alpha-tocopheryl acetate supplementation on iron-induced lipid oxidation of turkey breast, thigh, liver and heart tissues

Twenty-five 12-week-old turkeys randomly divided into five groups were given a basal diet, or a basal diet supplemented with 200 mg alpha-tocopheryl acetate/kg, or 100 mg oregano oil/kg or 200 mg oregano oil/kg, or 100 mg oregano oil plus 100 mg alpha-tocopheryl acetate/kg diet, for 4 weeks prior to slaughter. Breast, thigh, liver and heart tissues were subjected to iron-induced lipid oxidation, the extent of which was determined by third-order derivative spectrophotometry. Results showed that dietary oregano oil at the inclusion level of 200 mg oregano oil/kg diet was more effective in delaying lipid oxidation compared with the inclusion level of 100 mg/kg, but equivalent to the inclusion of 200 mg alpha-tocopheryl acetate/kg diet, which in turn was inferior to the combined inclusion of 100 mg oregano oil plus 100 mg alpha-tocopheryl acetate/kg, which was superior to all dietary treatments. Thigh tissue was more susceptible to oxidation than breast tissue, although it contained alpha-tocopherol at higher concentrations. Also, lipid oxidation in heart was relatively high, although it contained the highest alpha-tocopherol levels. This indicates that tissue alpha-tocopherol is one important factor influencing the level of lipid oxidation, but the distribution of lipids, iron and oregano oil in tissues must also be taken into consideration. Tissue alpha-tocopherol levels responded to dietary intake of 30-200 mg alpha-tocopheryl acetate/kg in the order heart > liver > thigh > breast. Breast, thigh and heart tissues from the oregano groups presented significantly (p < 0.05) higher levels of alpha-tocopherol compared with the control, the increase being positively correlated with the supplementation level. The increased levels of alpha-tocopherol in these tissues indicated that the dietary oregano oil exerted a protective action on alpha-tocopherol.     

Plasma and tissue vitamin E concentrations in sheep after administration of a single intraperitoneal dose of dl-alpha-tocopherol

Blood plasma and tissue Vitamin E concentrations were determined in 20 sheep following a single i.p. dose of 5 g of dl-alpha-tocopherol. In addition, five sheep were used as controls (no treatment and killed at d 0). From the 20 vitamin E-dosed sheep, 4 were slaughtered on d 3, 6, 10, 15 and 28 after dosing. There was a significant time effect in alpha-tocopherol concentrations in all tissues. In most tissues, the peak alpha-tocopherol concentration was at 3 d postdosing. Uptake varied among the different tissues examined. Three days postdosing, a large uptake of vitamin E by the liver was observed; this supports the concept that hepatic tissues are a target organ for vitamin E action. Also at 3 d uptake was pronounced in spleen and lung. Vitamin E concentrations in the other body tissues at d 3 postdosing increased considerably, but to a lesser degree than those in liver, spleen and lung. Vitamin E concentration in all tissues declined 3 d after i.p. dosing.     

Assessment of the influence of dietary vitamin E on sows and offspring in three parities: reproductive performance, tissue tocopherol, and effects on progeny

Sixty crossbred (Yorkshire-Hampshire X Duroc) gilts were fed one of four corn-soybean meal diets fortified with .3 ppm Se and 0, 16, 33, or 66 IU of DL-alpha-tocopheryl acetate/kg. The study was conducted over a three-parity period to evaluate sow reproductive performance and the vitamin E tissue status of both sows and progeny at various time periods postcoitum and(or) postpartum. The basal diet averaged 8.4 mg of alpha-tocopherol/kg and .38 ppm of Se. Although litter size at birth was lowest (P less than .15) when sows were fed the basal diet, a higher incidence of agalactia when sows were fed the lower dietary vitamin E levels resulted in an increased (P less than .05) litter size at 7 d postpartum as dietary vitamin E increased. Sow serum alpha-tocopherol increased (P less than .01) at each measurement period as dietary vitamin E level increased. Colostrum and milk alpha-tocopherol concentrations increased (P less than .01) as dietary vitamin E level increased, and colostrum values were three to five times higher than at later milks. Colostrum alpha-tocopherol declined by parity from sows fed less than or equal to 16 IU/kg but was similar at each parity for sows fed greater than or equal to 33 IU/kg, resulting in a dietary vitamin E x parity interaction (P less than .01). The Se content of sow milk declined with parity but was not affected by dietary vitamin E level. Sow liver tocopherol at weaning (28 d postpartum) increased (P less than .01) as dietary vitamin E increased and increased with parity (P less than .05). Pig serum and liver alpha-tocopherol concentrations were elevated at birth and 7 and 28 d of age as sow dietary level of vitamin E increased. Upon weaning, pigs were fed a torula yeast-dextrose diet that contained 3.0 mg of alpha-tocopherol/kg and .32 ppm Se for a 28-d postweaning period. Liver and serum alpha-tocopherol concentrations declined during the postweaning period. Evidence of the vitamin E deficiency occurred at 28 d postweaning in the progeny from sows fed the basal diet or 16 IU of vitamin E; the incidence was more prevalent in the pigs from Parities II and III. These results suggest that a supplemental level of 16 IU of vitamin E/kg of diet was inadequate for the reproducing sow; higher levels are justified, particularly when females are retained in the herd for several parities.     

Vitamin E requirement of growing swine

The vitamin E requirement of growing pigs was estimated on the basis of prevention of morphological signs of deficiency. Five groups of pigs were fed a barley-based diet low in vitamin E that contained 16 mg of DL-alpha-tocopheryl acetate equivalents/kg and .1 ppm of Se for 4 wk (depletion I). This period was followed by 7 wk of supplementation, during which the groups received 0, 15, 45, 135 and 405 mg of supplemental DL-alpha-tocopheryl acetate/kg diet. Finally, all the animals were fed the low vitamin E diet for 7 wk (depletion II). To follow the vitamin E concentration in serum and tissues, blood samples were collected and biopsies were taken from skeletal muscle, adipose tissue and the liver throughout the experiment. The peak vitamin E value was observed in the liver, followed by the adipose tissue and then skeletal muscle. The liver responded rapidly to changes in dietary vitamin E intake, whereas the adipose tissue and the skeletal muscle reacted at a slower rate. In spite of the abundant occurrence of the different vitamin E isomers in the feed, alpha-tocopherol was the main isomer detected both in the serum and in the tissues. The activity of glutathione peroxidase in serum increased with age but was independent of the serum vitamin E concentration. In the unsupplemented group all animals suffered from the vitamin E and Se deficiency syndrome (VESD) in an acute or chronic form. A total of 31 mg of DL-alpha-tocopheryl acetate/kg diet (16 mg of naturally occurring vitamin E and 15 mg as supplementation) equivalent to 2.5 IU vitamin E/g polyunsaturated fatty acids (PUFA) was enough to prevent the development of VESD. In view of the large individual variations of vitamin E concentration in target organs, and to obtain a certain safety margin for prevention of VESD in growing pigs, a supplement of 30 mg of DL-alpha-tocopheryl acetate/kg diet is recommended.