Effect of Dietary Fat Quality and Vitamin E on the Antioxidant Potential of Pigs

A randomized blocked factorial experiment was conducted with 90 young pigs. From 4 to 11 weeks of age the pigs were kept in individual pens and fed a selenium supplemented basal diet consisting mostly of propionic acid treated barley, soybean meal and dried skim milk, and containing < 0.5 mg vitamin E per kg. The treatment factors during this period were 3 dietary levels of added vitamin E (nil, 10 and 30 mg/kg) and a 6 % supplement of fresh or oxidized fat (2/3 lard and 1/3 herring oil). From 11 weeks of age until slaughter at 90 kg the pigs received the vitamin E supplements but no fat or dried skim milk. The basal diet for this later experimental period was based on untreated dry barley. Blood samples collected during the period of investigation were examined for vitamin E and for resistance against erythrocyte lipid peroxidation (ELP) in order to evaluate the antioxidant status.Analysis of variance and Student’s t-test on least squares means showed the ELP to be influenced independently by the vitamin E supplement and, during the fat feeding period, by the quality of the fat supplement, with the highest peroxidation resistance (low ELP) in the groups fed fresh fat and a high level of vitamin E. Blood vitamin E level was only influenced — positively — by the vitamin E supplement although variations in the feed vitamin E level below 10–15 mg vitamin E per kg did not result in corresponding variations in measurable blood vitamin E concentrations. In the same low range of vitamin E in the feed there was a statistically significant difference in ELP values between the different vitamin E treatment groups. No clinical manifestations of selenium-vitamin E deficiency were observed in the pigs.The ELP and the plasma vitamin E levels observed would seem to suggest that a total of 15 mg vitamin E per kg barley-based feed will not always be sufficient for growing pigs.     

Glutathione Peroxidase Activity and Erythrocyte Lipid Peroxidation as Indices of Selenium and Vitamin E Status in Young Pigs

A randomized, blocked 2³ factorial experiment was conducted with 48 pigs from sows fed a diet low in selenium and vitamin E. From 3 to 12 weeks of age the piglets were kept in single pens and fed a basic diet consisting mostly of barley, dried skim milk, soybean meal and dried yeast, and containing 55 µg selenium and 3 mg vitamin E per kg. The treatment factors — i.e. feed supplements — were 2 levels of Se (nil, 60 µg/kg), 2 levels of vitamin E (nil, 50 mg/kg), and 2 levels of the feed antioxidant ethoxyquin (nil, 150 mg/kg). Blood samples, collected at termination of the experiment, were examined for glutathione peroxidase activity (GSH-Px) and resistance against erythrocyte lipid peroxidation (ELP) to evaluate Se and vitamin E status, respectively. Analysis of variance showed the GSH-Px activity to be litter-dependent (P < 0.001) and influenced by selenium supplementation (P < 0.001) but not by the other supplements or by interactions between supplements. Resistance against ELP was influenced only by vitamin E supplementation (P < 0.001). GSH-Px and ELP thus seem to be valuable and simple methods for evaluating, respectively, Se status and vitamin E status in growing pigs.     

Vitamin E status of healthy Swedish cattle

Using high pressure liquid chromatography the serum concentration of vitamin E was measured in dairy cows fed either hay or silage as their main roughage, in calves fed milk-replacer, and in young intensively fed bulls. The concentrates fed to the cows, calves and bulls were supplemented with 5–10, 25 and 5–10 mg DL-α-tocopheryl acetate per kg, respectively, and the milk-replacer for the calves was supplemented with 50 mg DL-α-tooopheryl acetate per kg powder. Cows fed silage as their main roughage had higher serum vitamin E concentrations (: 3.8–5.2 mg/l) than cows fed only hay (: 2.5–4.1 mg/1). Lactating cows had higher vitamin E concentrations than dry cows (: 4.1–5.2 and 2.5–3.8 mg/l, respectively) and calves and bulls had much lower vitamin E concentrations (: 1.4 and 1.2 mg/l, respectively) than cows. Thirty per cent of the calves and 41 % of the bulls had serum vitamin E concentrations less than 1.0 mg/l, suggesting that in these animals the conventional level of supplementation of feeds with DL-α-tocopheryl acetate in Sweden is probably inadequate for the prevention of nutritional muscular degeneration and other negative effects.     

Effect of dietary linoleic acid concentration and vitamin E supplementation on cell desquamation and susceptibility to oxidative damage of pig jejunal mucosa

Sixty Large White × Great York pigs weighing approximately 60 kg were individually fed on six experimental diets. The experiment was organized in a 3 × 2 factorial arrangement design with three different fat sources and a basal or supplemented (200 mg/kg diet) level of α-tocopheryl acetate. All diets contained the same concentration of saturated fatty acids (15 ± 0.2 g/kg dry matter) but differed in the concentration of C18 : 2 (14 ± 0.5, 18 ± 0.4 and 21 ± 0.6 g/kg) and monounsaturated fatty acids (19 ± 0.2, 15 ± 1.2 and 10 ± 1.3 g/kg). No effect of dietary treatment was observed on weight gain and feed consumption. A histological study of the jejunal mucosa showed lower cell desquamation in groups containing a supplemental level of α-tocopheryl acetate (p=0.080). A higher cell desquamation was found in the groups fed diets containing the higher concentration of C18 : 2 (p=0.087). We also observed an interaction effect (p < 0.001) of dietary fat source and vitamin E supplementation on jejunal cell desquamation in which the effect of dietary vitamin E was lower when diets with a low concentration of C18 : 2 were administered. In vitro- induced oxidation of jejunal mucosa homogenates was lower in pigs fed diets supplemented with α-tocopheryl acetate (p < 0.002). The dietary concentration of C18 : 2 significantly affected oxidation of pig jejunal mucosa (p < 0.002).     

Effect of dietary copper and vitamin E supplementation, and extensive feeding with acorn and grass on longissimus muscle composition and susceptibility to oxidation in Iberian pigs

The objective of this study was to assess the effect of dietary copper and/or vitamin E supplementation on composition and oxidation of M. longissimus in Iberian pigs and to compare it with meat samples from pigs produced extensively and fed with acorn and grass. Grass had the highest α-tocopherol content (> 150 mg/kg DM), while acorns had the highest copper concentration (78.1 mg/kg DM). Dietary treatment did not affect copper composition in muscle and no interactions were detected between copper and α-tocopherol. The α-tocopherol content in muscle from pigs fed diets supplemented with α-tocopheryl acetate (100 mg/kg feed) was 1.5 times greater (p < 0.0001) than those from pigs receiving a basel diet. M. longisssimus dorsi from pigs fed extensively had a higher concentration of α-tocopherol than those fed in confinement with the basel level of α-tocopheryl acetate, but lower values than pigs fed supplemented levels. Total n -3 fatty acids (p < 0.02) and hematin (p < 0.0001) concentrations were significantly higher in muscle from pigs fed extensively than when fed in confinement. Muscle homogenates from Iberian pigs fed in extensive conditions showed significantly (p < 0.02) higher susceptibility to oxidation than those from pigs fed mixed diets. Dietary α-tocopheryl acetate supplementation (100 mg/kg feed) significantly (p < 0.05) reduced lipid oxidation of muscle, while dietary copper concentration did not modify susceptibility to lipid oxidation.     

A water-soluble β-glucan improves growth performance by altering gut microbiome and health in weaned pigs

Beta-glucan has been shown to have a beneficial effect on gastrointestinal health. This experiment was conducted to investigate the effects of β-glucan isolated from Agrobacterium sp. ZX09 on growth performance and intestinal health of weaning pigs. A total of 108 weaned pigs (21 d of age; 6.05 ± 0.36 kg) were randomly divided into 3 groups (6 pens/group; 6 pigs/pen), and the groups were each treated with the following diets: 1) basal diet, 2) basal diet supplemented with 20 mg/kg olaquindox, 3) basal diet supplemented with 200 mg/kg β-glucan, for 21 d. Compared with the control group, pigs fed with 200 mg/kg β-glucan had greaterBW, average daily gain and duodenal villus height to crypt depth ratio (P < 0.05). Olaquindox increased the duodenal or jejunal villus height of pigs compared with β-glucan. Compared with the control group, β-glucan tended to increase the occludin mRNA expression in the jejunum (0.05 < P < 0.10). Beta-glucan enriched the beneficial microbiota in the ileum of pigs (P < 0.05). In conclusion, β-glucan may promote growth performance by improving intestinal health and increasing beneficial microbiota of weaned pigs. The study results will provide valuable theoretical guidance for the utilization of β-glucan in weaned pigs.     

Importance of diet of dam and colostrum to the biological antioxidant status and parenteral iron tolerance of the pig

Fifteen second-parity sows were used to determine the importance of vitamin E (E) and selenium (Se) supplementation of the sow's diet and colostrum consumption by the neonatal pig on tolerance to parenteral iron. Selenium (.1 ppm) and E (50 IU/kg) supplementation of the diet of the sow increased plasma tocopherol and Se concentrations, but did not increase plasma glutathione peroxidase (GSH-Px) activity. Colostrum had greater concentrations of E (primarily alpha-tocopherol) and Se than milk. Plasma biological antioxidant status (tocopherol level and GSH-Px activity) of pigs at birth was very low, but by 2 d of age had increased, especially in alpha-tocopherol (nearly a 20-fold increase). Liveability and body weight gain of pigs were not affected by the pre-colostrum iron injection (200 mg Fe as gleptoferron); however, plasma tocopherol concentrations of Fe-injected pigs were lower and plasma Se concentration and GSH-Px activities were higher at 2 d of age than values of pigs not receiving parenteral Fe. Supplementation of the dam's diet with E and Se maintained high tocopherol and Se levels in her colostrum and milk and a high biological antioxidant status in her pigs throughout the nursing period.     

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.     

Vitamins a, e and selenium blood levels in the fat cow syndrome

Blood plasma analyses for vitamins A, E and selenium were performed from calving to five weeks of lactation in 29 cows. Twelve of the 29 cows had fat cow syndrome. The healthy cows had significantly higher (P<0.01) plasma vitamin A (40 μg/dL) and vitamin E (5 μg/mL) levels than the cows with fat cow syndrome (29 μg vitamin A/dL and 3 μg vitamin E/mL). At parturition, vitamin A level in plasma was low (25 μg/dL) but increased progressively thereafter (up to 51 μg/dL) in healthy cows, whereas cows with fat cow syndrome had lower levels of vitamin A, bordering on deficiency. The possible role of vitamin E in the alleviation of fat cow syndrome by affecting oxidation-reduction reactions in the liver is discussed. Significant (P<0.01) difference was not observed in selenium blood plasma level (35 ng/mL) between the two groups of cows or in another random group of 12 cows clinically affected by fat cow syndrome.     

Dietary Induction of Mulberry Heart Disease and Hepatosis Dietetica in Pigs I. Nutritional Aspects

Two trials were conducted, involving 48 Yorkshire specific pathogen-free pigs, three to four weeks old, to investigate diets which would result in a high incidence of deaths from mulberry heart disease and hepatosis dietetica in pigs. Diets based on ground corn with torula yeast resulted in a high incidence of death. Protein supplements of dried skim milk or soybean meal with corn did not induce a high incidence of death. Diets supplemented with torula yeast had the lowest selenium concentration and highest _α-tocopherol concentration of the diets investigated and resulted in lower liver selenium concentrations. A higher frequency of hepatosis dietetica, mulberry heart disease, skeletal muscle degeneration and exudative diathesis was observed in pigs fed the low level selenium diets containing torula yeast.     

Therapeutic effects of vitamin E supplementation in 4 dogs with poor semen quality and low superoxide dismutase activity in seminal plasma

Four dogs with poor semen quality, low seminal plasma superoxide dismutase (SOD) activity and low blood plasma testosterone (T) levels were orally administered one vitamin E tablet containing 50 mg α-tocopheryl acetate per dog daily for 4 weeks. The mean values of semen quality were temporarily improved after the start of vitamin E treatment and the values of 4, and 5 weeks after that were significantly different from those before the treatment (P<0.05–0.001). The mean blood plasma T and seminal plasma SOD activity values slightly increased in the 4 dogs after the treatment. The results of the present study indicate that poor semen quality in dogs with low seminal plasma SOD can be improved by vitamin E treatment.     

Modulation of jejunal mucosa-associated microbiota in relation to intestinal health and nutrient digestibility in pigs by supplementation of β-glucanase to corn–soybean meal-based diets with xylanase

This study aimed to evaluate the effects of increasing levels of β-glucanase on the modulation of jejunal mucosa-associated microbiota in relation to nutrient digestibility and intestinal health of pigs fed diets with 30% corn distiller’s dried grains with solubles and xylanase. Forty pigs at 12.4 ± 0.5 kg body weight (BW) were allotted in a randomized complete block design with initial BW and sex as blocks. Dietary treatments consisted of a basal diet with xylanase (1,500 endo-pentosanase units [EPU]/kg) and increasing levels of β-glucanase (0, 200, 400, and 600 U/kg) meeting nutrient requirements and fed to pigs for 21 d. Blood samples were collected on day 19. On day 21, all pigs were euthanized to collect intestinal tissues and digesta. Tumor necrosis factor-alpha, interleukin (IL)-6, and malondialdehyde were measured in the plasma and mid-jejunal mucosa. Viscosity was determined using digesta from the distal jejunum. Ileal and rectal digesta were evaluated to determine apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients. Mucosa samples from the mid-jejunum were utilized for microbiota sequencing. Data were analyzed using the MIXED procedure on SAS 9.4. Overall, increasing dietary β-glucanase tended to increase (linear; P = 0.077) the average daily gain of pigs. Increasing dietary β-glucanase affected (quadratic; P < 0.05) the relative abundance of Bacteroidetes, reduced (linear; P < 0.05) Helicobacter rappini, and increased (linear, P < 0.05) Faecalibacterium prausnitzii. β-Glucanase supplementation (0 vs. others) tended to increase (P = 0.096) the AID of crude protein in the diet, whereas increasing dietary β-glucanase tended to increase (linear; P = 0.097) the ATTD of gross energy in the diet and increased (linear; P < 0.05) the concentration of IL-6 in the plasma of pigs. In conclusion, increasing β-glucanase up to 600 U/kg feed in a diet containing xylanase (1,500 EPU/kg) modulated mucosa-associated microbiota by increasing the relative abundance of beneficial bacteria and reducing potentially harmful bacteria. Furthermore, increasing β-glucanase up to 600 U/kg feed in a diet containing xylanase (1,500 EPU/kg feed) enhanced the status of the intestinal environment and nutrient utilization, as well as reduced systemic inflammation of pigs, collectively resulting in moderate improvement of growth performance. Supplementing β-glucanase at a range of 312 to 410 U/kg with xylanase at 1,500 EPU/kg feed showed the most benefit on jejunal mucosa-associated microbiota and reduced systemic inflammation of pigs.     

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.     

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.     

Dietary fat modulates dl-α-tocopheryl acetate (vitamin E) bioavailability in adult cockerels

1. A trial was designed to assess the effect of fat supplementation (amount and type of fatty acids) on vitamin E bioavailability in adult cockerels.

2. A total of 60 birds were force-fed three different diets: a semi-purified diet without added fat (Control diet) or supplemented with 3% fat as linseed (Linseed diet) or hydrogenated coconut oil (Coconut diet). The three experimental diets were also supplemented with dl-α-tocopheryl acetate to provide 40 mg vitamin E per bird.

3. After one week of depletion, blood was collected from the wing vein before (baseline) and 6, 12, 24 and 96 h after the gavage. Plasma samples were analysed for their α-tocopherol, cholesterol and triglycerides concentrations.

4. Results showed that the addition of 3% fat in the experimental diet increased post-gavage plasma α-tocopherol response by 153% for Linseed diet and by 75% for Coconut diet (P < 0.0001) compared to the Control group. Furthermore, the plasma α-tocopherol response observed with the Linseed diet was 44% greater than that observed with the Coconut diet (P < 0.0001). There was no effect of treatments on either plasma triglycerides (P = 0.91) or cholesterol (P = 0.45) responses.

5. In conclusion, this study shows that the addition of 3% fat to the diet significantly increases dl-α-tocopheryl acetate bioavailability in adult cockerels. Supplementation of fat rich in unsaturated fatty acids also leads to a higher dl-α-tocopheryl acetate bioavailability than fat rich in saturated fatty acids.

     

Influence of Dietary Sodium Selenite on Tissue Selenium Levels of Growing Pigs

Twenty Norwegian Landrace pigs were divided into 5 groups and fed a basal diet consisting of a mixture of dried skim milk and whey powder together with ground barley. The diet was supplemented with 0, 0.2, 0.8, 1.2 and 2.2 μg selenium as sodium selenite and was fed for 12 weeks. The muscle selenium level was increased by a factor of about 4 and the liver selenium by a factor of about 12 when the dietary selenium supplement was increased from zero to 2.2 μg/g. There was a significant linear correlation between dietary selenium and selenium concentrations in tissues. Possible benefit for humans consuming meat from animals having received the selenium doses used in this experiment are discussed.dietary selenium; tissue levels; pigs.     

Study of immune response in pigs fed with high vitamin E-dosages

The effects of long-term vitamin E-supplementation on phagocytic cells, lymphocyte sub-populations, and SWC3+ cell count were studied in pigs. Eighteen weaned pigs were divided into three groups: 1) 100 mg DL-alpha tocopheryl acetate/kg diet, 2) 200 mg DL-alpha tocopheryl acetate/kg diet, 3) control group (basic feed with 10 mg DL-alpha tocopheryl acetate/kg diet). The examination of the immune indices was performed on day 120 of feeding the supplemented diets. The higher dietary levels of vitamin E resulted in increased serum concentration of alpha-tocopherol for both experimental groups (p < 0.05) and there were no significant differences in counts of CD2+, CD4+, CD8+, B lymphocytes nor SWC3+ cells among the groups. Similarly, vitamin E supplementation did not affect the functions of phagocytic cells tested.     

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.     

营养水平和酵母硒对烟台黑猪屠宰性能及肉品质的影响

本试验旨在研究不同营养水平及酵母硒对胴体性状和肉质指标的影响。选取体况良好、体重为(70.30±1.30)kg的烟台黑猪48头,公、母各半,随机分成4个处理组,每个处理组4个重复,每个重复3头。Ⅰ组饲喂低营养水平日粮(消化能11.19 MJ/kg、粗蛋白质12.28%),Ⅱ组饲喂低营养水平+0.5 mg/kg酵母硒日粮,Ⅲ组饲喂高营养水平日粮(消化能13.11 MJ/kg、粗蛋白质14.73%),Ⅳ组饲喂高营养水平+0.5 mg/kg酵母硒日粮。试验预试期为7 d,正试期为105 d。结果表明:与低营养水平组相比,高营养水平能够极显著提高烟台黑猪的胴体重(P0.01),显著提高眼肌面积和瘦肉率(P0.05);营养水平和酵母硒对烟台黑猪的肉质性状影响均不显著(P0.05),其中高营养水平有提高其肌内脂肪及肌肉风味氨基酸含量的趋势(P0.05);与未添加酵母硒组相比,添加酵母硒能够显著提高肌肉中油酸含量(P0.05),有提高其肌肉中亚油酸含量的趋势(P0.05),能够极显著提高其肌肉中硒元素含量(P0.01);营养水平和酵母硒对屠宰性能、胴体性能、肉品质等无互作效应(P0.05)。由此可见,在本试验条件下,高营养水平能够提高烟台黑猪肌内脂肪及风味氨基酸的含量;酵母硒有利于提高烟台黑猪肌肉中油酸含量,有提高亚油酸含量的趋势。