The effect of supplementation of vitamin E and herb extracts on chemical composition, quality traits and oxidative status of pork was evaluated. Total eighty hybrid pigs - crosses of Landrace sows and Hampshire x Pietrain boars were involved into the experiment. Pigs were divided to one control and three experimental groups (each of 20 animals with equal number of gilts and castrates). All pigs were heterozygotes on RYR1 gene. Experimental groups received diet with supplement of vitamin E (500 mg/kg feed) for 30 days before slaughter or supplement of this vitamin in combination with lemon balm extract (100 ml/pig/day) and/or oregano extract (60 ml/pig/day) for 10 days before slaughter. Supplementation of vitamin E singly or in combination with herb extracts had no effect on chemical composition of pork. Vitamin E significantly (P<0.05) increased the concentration of ?-tocopherol in longissimus dorsi muscle. Electrical conductivity in muscle 24 h post mortem was significantly lower in all experimental groups in comparison to control group (4.96 - 5.06 vs. 6.12 ?S). Significant positive effect of herb extracts on meat colour (parameter ?a?) in stored pork was found (3.22 and 3.41 vs. 2.54). Lipid oxidation measured as TBARS value was decreased significantly in groups with vitamin E and/or vitamin E + lemon balm extract after 5-days storage of pork (0.193 and 0.190 vs. 0.267 mg/kg).

An experiment was conducted to evaluate the effect of pea-based diet fed to growing and finishing pigs on performance, carcass and meat quality. Thirty pigs (Slovak White Meaty or crossbred Slovak White Meaty × Pietrain) were tested for the malignant hyperthermia (MH) syndrome using a DNA based test. Pigs were allotted to control and experimental groups (of 10 pigs each, equal for normal - NN and he-terozygotes - Nn and equal for barrows and gilts) with 2 pigs per pen. Pigs receiving the control treatment were fed soybean meal diets. In all diets fed to experimental pigs the soybean meal was replaced by 30% of raw or extruded pea-based meal balanced on an isonitrogenous and isoenergetic level. Pig performance was monitored for the entire experimental period. At the conclusion of the experiment, carcass and meat quality were measured. The results did not show any effects of dietary treatments on average daily gain (P > 0.05). The evaluation of carcass composition showed no significant differences (P > 0.05) in backfat and lean percentage values between the control and experimental pigs. Chemical composition (total water, protein, intramuscular fat) and fatty acid profile did not differ among treatments (P > 0.05). The differences in the omega-6/omega-3 ratio were significant (P > 0.05) between animals fed the control ration with soybean meal and animals receiving the pea ration. No differences were observed between control and experimental pigs in pH (45 min and 24 h), colour (24 h), drip loss (24 h) and tenderness (5 day) measured with Warner-Bratzler instrument (P > 0.05). In conclusion, peas may replace the soybean meal in diets fed to growing and finishing pigs without negative influence on pig performance, carcass composition and meat quality.

The objective of this study was to evaluate the possibility of prediction of intramuscular fat (IMF) in live pigs using ultrasound method. Moreover, the accuracy of prediction at five different ultrasound intensity levels was investigated. Cross-sectional images of longissimus dorsi muscle (LD) at right last rib area, from hybrid pigs, were taken. Each pig was scanned at the same frequency (3.5 MHz) and at the five different ultrasound intensity levels 70%, 75%, 80%, 85% and 90% of total amplifying of sonograph, using the device ALOKA SSD-500. The video image analysis was used to predict IMF content (ultrasound intramuscular fat (UIMF) 70 to UIMF90). The second day after slaughter the dissection of right half carcass was done. A sample of LD at the last rib was taken for laboratory analysis of IMF content (LAIMF). Scatter plots with UIMF on the x-axis and LAIMF on the y-axis were constructed to account for individual variability within and between intensity levels. Correlations between LAIMF and UIMF were significantly different from zero (r = 0.40-0.52), except for correlation between LAIMF and UIMF90 (r = 0.14). Statistical model with LAIMF (the dependent variable), UIMF (the same model for each intensity level), live weight (the covariates) and sex (the fixed effect) was developed. Coefficients of determination (R-2) were 0.33, 0.38, 0.34, 0.25 and 0.17 with UIMF at the intensity level 70%, 75%, 80%, 85% and 90%. Root mean square errors ranged from 0.516% to 0.639%. Standard errors of individual prediction ranged from 0.523% to 0.649%. Goodness-of-fit of the model was also justified by testing the residuals for normality Although the results are not quite unequivocal in favour of the one intensity level, it seems that intensity levels 75% and 80% are the most suitable to predict IMF in live pigs. Further research is needed, mainly to increase accuracy of collecting, processing and evaluating the sonograms using video image analysis.

The objective was to study the effect of dietary magnesium oxide supplementation (Mgo) on glycogen and lactate level in muscle post mortem and on carcass and pork quality traits. Twenty four crossbred (Large White x White Meaty)x( Pietrain x hampshire) barrows and gilts were tested by DNa probe on malignant hyperthermia (Mh) and equal heterozygotes (n=12) and normal on Mh (n=12) pigs were taken in experiment. Dietary MgO supplementation (3.6 g additional magnesium per pig for 5 days prior to slaughter) increased plasma magnesium level (P 0.05) between control and magnesium supplement ed pigs. Comparison of meat quality traits indicates that MgO supplementation to pigs raised the ph in the LD muscle at 45 min after slaughter and significant differences (P<0.05) were found between homozygotes and heterozygotes pigs. Pigs fed the MgO supplemented diet had lower (P<0.05) percentage of drip loss in both normal and heterozygotes compared to control heterozygotes pigs. Significant differences were found in glycogen and lactate levels in LD between heterozygotes control group and normal MgO supplemented pigs.

the effects of addition of vitamin d3 and vitamin e to pig diet on blood plasma calcium concentration and meat quality (longis simus muscle) were investigated. the treatment consisted of supplementation with vitamin e (500 mg a-tocopheryl acetate/kg diet) for 30 days and vitamin d3 (500,000 Iu/d) for 5 days to growing pigs before slaughtering these fullgrown ones. animals fed with vitamin d3 exhibited higher (P<0.01) plasma calcium concentration compared with control pigs. the dietary supplementation of vitamin e significantly (P<0.05) increased the concentration of a-tocopherol in meat (longissimus muscle). Lipid oxidation meas ured as mda (malondialdehyde) was positively influenced by the supplementation with vitamin e. Vitamin d3 supplementation resulted in higher (P<0.05) a* values of loin chops at 5 d of shelf storage. Vitamin d3 and vitamin e supplementation did not affect other meat quality characteristics or tenderness (quantified via Warner-Bratzler shear force).

In total thirty pigs (Slovak Meaty) defined by DNA based test as not susceptible to malignant hyperthermia (non-mutant on RYR1) were used in the experiment. Treatment consisted in supplementation of vitamin E (500 mg α-tocopherol/kg diet as α-tocopherol acetate) (group E) and the same doses of vitamin E plus vitamin C (200 mg L-ascorbic acid/kg diet) (group E + C) to finishing pigs for the last 30 days before slaughter. The higher dietary vitamin E level resulted in higher levels of α-tocopherol in fresh (24 h), chill-stored (5 days, 4°C), chill-stored and cooked (80°C) and frozen meat (3 months, -25°C), (P < 0.05). Higher dietary vitamin C resulted in higher levels L-ascorbic acid in fresh and chill-stored meat (P < 0.05) but no significant differences vs. control pigs were observed in cooked and frozen meats. Supplementation with vitamins E and C (group E + C) had positive effects on pH (45 min) (P = 0.06) and on drip loss (P < 0.05) values as compared to control group. The rate of oxidation (malondialdehyde-MDA production) by stimulation with Fe2+/ascorbate (incubation of muscle LD for 0 and 30 min) was higher in control group as compared to both experimental groups (P < 0.05). Positive effects of vitamin E on oxidative stability measured as thiobarbituric acid reactive substances (TBARS, MDA) were observed mainly in chill-stored meat (P < 0.05). Using TBARS method, no additional effect of vitamin C on oxidative stability of fresh, chill-stored, cooked and frozen meat was found. In conclusion, supplementation of the combination of vitamin E (500 mg α-tocopherol/kg diet) and vitamin C (200 mg L-ascorbic acid/kg diet) for 30 days before slaughter improved meat quality values (drip loss, pH), however, it seems to depend on the genetic background of animals (occurrence of mutation on RYR1). Oxidative stability of meat lipids measured as TBARS value can be improved by vitamin E supplementation to feed.

The effects of addition of vitamin E to pig diet and of calcium ascorbate injection in meat on the antioxidative status and meat quality (longissimus muscle) of pigs were investigated. The treatment consisted of supplementation with vitamin E (500 mg alpha-tocopheryl acetate/kg diet) for a minimum of 30 days to growing-finishing pigs before slaughter. Furthermore, meat samples (longissimus muscle) were injected with 10% by weight of a 1.5% calcium ascorbate solution. The dietary supplementation of fat soluble antioxidant vitamin E significantly (P < 0.05) increased the concentration of a-tocopherol in meat (longissimus muscle). Lipid oxidation measured as TBARS, and antioxidative capacity (Fe2+/ascorbate induced) of meat were significantly (P < 0.05) influenced by the supplementation with vitamin E, and the pH(1) and driploss was improved. Water soluble antioxidant calcium ascorbate, injected in meat, increased the concentration of calcium (P < 0.05) and ascorbic acid (P < 0.05), and stabilized the colour ("a" value; P < 0.05) in chill-stored meat and improved (P < 0.05) the antioxidative capacity (Fe2+/ascorbate induced). Further research is needed to optimise the dosage.

The effects of feeding a high level of organic selenium on the level of selenium, antioxidative status of m. longissimus lumborum et thoracis (MLLT) and m. semimembranosus (MSM) and meat quality of pigs (defined on malignant hyperthermia status, DNA based test) were investigated. Treatments consisted in supplementation of organic selenium (0.3 mg Se/kg diet) for the last 97 days to finishing pigs (basic diet with 0.18 mg Se/kg diet) before slaughter. MLLT was further examined for pH (45 min, 24 h), colour and conductivity (24 h), drip loss (48 h) and myofibrillar fragmentation index (MFI, 5 days). Chemical composition (protein, intramuscular fat) was also estimated. Concentration of Se (spectrofluorometric method) and antioxidative status (rate of oxidation by stimulation with Fe2+/ascorbate, production of malondialdehyde - MDA) were estimated in muscle samples obtained post mortem. The level of selenium was more than twice higher (P < 0.05) in muscles from pigs treated with higher selenium than in controls (0.377 vs. 0.922 mg/kg - MLLT and 0.377 vs. 0.836 mg/kg - MSM). The rate of oxidation was positively (P < 0.05) influenced by Se supplementation. Tendencies to lower drip losses were observed in MLLT of pigs supplemented with Se but the differences were not significant (P > 0.05). We concluded that dietary organic Se supplementation (0.3 mg Se/kg diet) to basic diet (0.18 mg Se/kg diet) of finishing pigs significantly increased the selenium concentration and improved the antioxidative status of muscle tissue.

Twenty four crossbred (Large White, White Meaty, Pietrain, Hampshire) pigs were tested by DNA probe for a mutation on the ryanodine receptor RYR1 (malignant hyperthermia-MH). An equal number of pigs heterozygote (monomutant-MON) and normal on MH (nonmutant-NON) were used in the experiment. The pigs were fed finisher feed (control group) or finisher feed supplemented with magnesium (3.6 g MgO per pig per day; MgO group) for 5 days prior to slaughter. Pigs fed the diet supplemented with MgO had higher plasma Mg concentrations. Phosphorus nuclear magnetic resonance (31P NMR) measurements on postmortem (15 min) muscle samples (longissimus muscle) showed the highest phosphocreatine levels in normal pigs fed MgO (P<0.05). The MgO supplementation caused increased Ca2+ uptake and Ca2+ ATPase activity only in normal (NON) pigs. ATPase activity was lowest (P<0.05) in heterozygote control pigs. Pigs fed MgO supplemented diet had higher pH (45 min postmortem). A significant lower pH (P<0.05) was obtained in heterozygous (MON) control pigs. Also pigs fed with MgO had lower percentage of drip losses and significant differences (P<0.05) were obtained between heterozygous (MON) pigs. The results indicate that dietary MgO supplementation can improve parameters of muscle energetic metabolism, Ca2+ uptake and meat quality (pH, drip loss).

The objective of this research was to examine the impact of supplementation with magnesium oxide (MgO) oil the fatty acid composition, antioxidative capacity and quality parameters, determined oil 24 pork longissimus muscles (LD). Crossbred pigs equal for halothane genotypes (12 normal, nonmutant - NON, 12 heterozygous, monomutant - MON) and sex, were fed a diet supplemented with MgO (3.6 g magnesium daily) for 5 days prior to the slaughter. There was a tendency of higher intramuscular fat, a significant higher concentration of C17:0 and C18 2n-6, C22: 5n-3 and the total amount of n-3 fatty acids (P<0.05) in LD of supplemented pigs. A higher resistance to ill vitro stimulation of peroxidation in muscle With MgO supplementation was observed. Increasing dietary level of MgO resulted in higher concentration (P<0.05) of magnesium in plasma. Genotype had significant effects oil some quality indicators. Pigs fed the MgO supplemented diet had higher muscle pH compared to pigs fed the control diet. Significant differences (P<0.05) were received between control heterozygous pigs and MgO normal pigs. The LD of pigs fed diets supplemented with MgO had lower percentage of drip loss compared to pigs fed the control diet. Significant differences (P<0.05) were found between heterozygotes control group and the other three groups. In conclusion MgO supplementation could not only improve post mortem pH rate breakdown and water holding capacity but also the antioxidant stability.

The effect of feeding a high level of vitamin E on the level of alpha-tocopherol in muscle tissue and on the antioxidative status of longissimus thoracis (LT) and psoas major (PM) of bulls (Slovak Pied, n = 16) was investigated. Treatments (n = 8) consisted in supplementation of vitamin E (1 000 mg alpha-tocopherol acetate/head/day) for the last 100 days before slaughter (average 540 kg live weight). Concentration of alpha-tocopherol was estimated from ante-mortem biopsy (taken before slaughter) samples of m. semitendinosus (ST) and post-mortem samples of LT and PM. Total protein, total water, intramuscular fat, total pigments; pH 48 h post-mortem and rate of oxidation by stimulation with Fe2+/ascorbate were estimated in LT and PM muscles. The level of alpha-tocopherol was higher (P < 0.05) in muscles, (LT, PM and ST) from bulls treated with higher vitamin E than in controls in the order PM > ST > LT The level of alpha-tocopherol can be controlled also ante-mortem (ST muscle). The rate of oxidation was positively influenced by vitamin E supplementation in the order PM > LT We concluded that dietary vitamin E supplementation (1000 mg alpha-tocopherol acetate/head/day) for the last 100 days to finishing bulls increases alpha-tocopherol concentrations in muscle and improves the antioxidative status of muscle tissue.

Phosphorus nuclear magnetic resonance ((31)P NMR) measurements were made to determine muscle energetic metabolism on muscle biopsy samples of heterozygote malignant hyperthermia (Nn) and normal (NN) pigs DNA tested on occurrence of mutation in RYR 1 gene. Biopsy samples (approx. 1 g) were obtained by spring-loaded biopsy instrument (Biotech, Slovakia) from Longissimus dorsi (LD) muscle at 80 kg live weight. The spectra were recorded at 121 MHz on a VXR 300 (Varian) spectrometer in 10 mm diameter tube (maintained at 39 °C) for 50 min. pH of bioptates after NMR measurements were also measured at 60 min. The changes in inorganic phosphate (Pi), phosophocreatine (PCr) and adenosine triphosphate (ATP) were faster in heterozygote malignant hyperthermia (MH; 29 crossbred White Meaty×Pietrain) than in normal (13 Duroc, Yorkshire and White Meaty). The values of PCr at 20 min and pH at 60 min after taking biopsy allowed discrimination between NN and Nn pigs and significant (P<0.05) differences were also found between two subgroups in heterozygote MH pigs with different rate of post mortem muscle metabolism. The values of PCr and pH as measured at definite time on the biopsies, were significantly (P<0.05) correlated with the rate of post mortem metabolism (pH) and with meat quality traits (r approx. 0.4-0.6). The (31)P NMR measurements pointed to impaired muscle energetic metabolism connected with the occurrence of mutation on the RYR 1 gene in heterozygote MH pigs.

The effect of feeding high levels of alpha -tocopherol and organic selenium (Se) to pigs on colour stability and on the susceptibility to oxidative deterioration was investigated. Treatments consisted of supplementation of vitamin E (200 mg/kg diet), organic Se (0.3 mg/kg diet) and both vitamin E and organic Se for the last 60 days to finishing pigs before slaughtering. Longissimus dorsi (LD) and psoas major (PM) muscles were examined after 2 and 7 days of storage on colour stability and on lipid peroxidation (measured as malondialdehyde equivalents). Rate of oxidation by stimulation with Fe2+/ascorbate was also estimated in LD samples obtained post mortem. In PM 7 days post mortem we found differences between control and groups of pigs supplemented with vitamin E and Se on reflectance, but significant differences (P<0.05) were found only in the vitamin E + Se group.Positive effects (P<0.05) of vitamin E and Se on colour in psoas major muscle refrigerated for 7 days are supported with significant (P<0.05) lower levels of TBARS values in pigs supplemented with vitamin E and organic Se as well. Supplementation with organic Se does not affect the oxidative stability of muscle tissue (longissimu dorsi) when the rate of iron-induced lipid oxidation was examined.Dietary Se had limited potential for enhancing the quality of pork carcasses (psoas major) and accentuating the effect of vitamin E on the oxidative stability of longissimus dorsi muscle was not found.

The effect of feeding a high level of vitamin E on the antioxidative status of longissimus dorsi muscle and meat quality of pigs was investigated, Treatments consisted of supplementation of vitamin E (200 mg/kg diet) for the last 60 days to finishing pigs before slaughtering. Longissimus dorsi (LD) muscle was examined after 2 and 5 days of storage for colour (reflectance), drip loss and shear force. alpha -Tocopherol level, total protein, intramuscular fat and pH (45 min post mortem) were also determined. Lipid peroxidation (thiobarbituric acid reactive substances - TBARS - measured as malondialdehyde equivalents) in 5 and 6 days after thawing of muscle samples and rate of oxidation by stimulation with Fe2+/ascorbate were estimated in LD samples. alpha -Tocopherol level was higher (P < 0.05) in LD from pigs treated with higher vitamin E than in controls (1.71 vs. 2.73 mg/kg). There were observed tendencies to lower drip losses and higher shear force in LD pigs supplemented with vitamin E. Inhibition of TBARS during storage (frozen and thawed) and rate of oxidation were positively influenced by vitamin supplementation. We concluded that dietary vitamin E supplementation (200 mg/kg diet) to pigs during the last 60 days of finishing increases the <alpha>-tocopherol concentration of tissue, reduces lipid peroxidation and improves the antioxidative status of muscle tissue.