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Both vitamin E and C have antioxidative properties and may act synergistically. To examine a possible interaction between vitamin E, C and oxidative stability in various tissues, 40 barrows (25-105kg body weight) were allocated to four cereal-based diets (13.4MJ digestible energy/kg, 168g crude protein/kg, 140mg dietary dl-α-tocopheryl acetate) which were supplemented with 0 (B), 150 (C100), 300 (C200) or 600 (C400)mg/kg crystalline ascorbic acid. The influence of storage time on these factors in m. longissimus dorsi samples (LD) was investigated. Samples of liver (LI), heart (HT), spleen (SP), backfat outer layer (BF) and LD were obtained. Dry matter, vitamin E, vitamin C and thiobarbituric acid reactive substances (TBARS) were analyzed in all investigated tissues and in addition color (L(∗), a(∗), b(∗) values) and drip loss measurements in LD at day 0, 1, 2, 3, 4 and 8 were collected. The treatments did not influence growth performance and slaughter data of the pigs. Neither the vitamin E nor the vitamin C content of investigated tissues showed differences due to feeding treatments. There was also a lack of response to the amount in TBARS. Parameters in LD samples were only affected by storage time and not by diets. The results show that dietary use of both vitamins simultaneously did not further improve qualitative characteristics of the investigated pork tissues.

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To investigate the influence and possible interactions of dietary vitamin E and C supplementation on vitamin content of both vitamins and oxidative stability of different pork tissues 40 Large White barrows from 25 kg to 106 kg were allocated to four different cereal based diets: Basal diet (B), dl-alpha-tocopherylacetate + 200 mg/kg (E), crystalline ascorbic acid + 300 mg/kg (C) or both vitamins (EC). At slaughtering samples of liver, spleen, heart, kidney, backfat outer layer, ham and M. tongissimus dorsi were obtained. Growth performance of the pigs and carcass characteristics were not influenced by feeding treatments. Dietary vitamin E supplementation had a significant effect on the vitamin E and alpha-tocopherol concentration in all investigated tissues. Backfat outer layer, liver, spleen, kidney and heart had higher vitamin E concentrations than ham and M. longissimus dorsi. Dietary vitamin C supplementation tended towards enhanced vitamin E levels except for ham samples. Therefore, some synergistic actions without dietary vitamin E supplementation between the two vitamins could be shown. The vitamin C concentration and TBARS were increased or at least equal in all tissues due to vitamin C supplementation. Dietary alpha-tocopherol supplementation resulted in lower TBARS in backfat outer layer (malondialdehyde 0.35 mg/kg in B vs. 0.28 mg/kg in E), but increased in heart and ham. When both vitamins were supplemented (EC) TBARS were lower in M. longissimus dorsi and backfat outer layer, equal in heart and higher in liver and ham compared to a single vitamin C supplementation. Rancimat induction time of backfat outer layer was 0.3 h higher in C compared to B and 0.17 h higher in EC than in E. Correlations between levels of both vitamins were positive for kidney (r = 0.169), M. longissimus dorsi (r = 0.499) and ham (r = 0.361) and negative for heart (r = -0.350). In liver and spleen no interaction could be found. In backfat outer layer vitamin E was positively correlated with rancimat induction time (r = 0.550) and negatively with TBARS (r = -0.202), but provided no evidence that dietary vitamin E supply led to better oxidative stability.

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An experiment with 40 female growing pigs from 27.4 to 106.5 kg body weight (BW) in individual pens was conducted to evaluate the effect of different chromium supplements (Cr-chloride, Cr-yeast and Cr-picolinate) according to 0.5 ppm Cr in the diet compared with a control diet without any additional chromium. The influence on growth performance and carcass as well as meat composition was studied. In comparison with the control diet body weight gain and feed conversion ratio in the finishing period (60 to 106.5 kg BW) were significant increased and lowered respectively in the treatment with Cr-chloride and with the other Cr supplements tendentially. The results of the carcass composition as well as the fatty acid profile of neutral and complex lipids in the muscle (M. longissimus dorsi) at the 10th rib did not indicate a statistically significant effect of the Cr supplements. Furthermore energy utilization on the base of digestibility was not affected. Concerning the Longissimus muscle area and the intramuscular fat content there were positive tendencies of the investigated Cr supplements.

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The role of nutrition in the pathogenesis of E. coli enterotoxaemia was studied in weaned pigs inoculated with a field strain of E. coli O139:K82(B):H 4. Feeds extremely low in nutrients (5% crude protein, 4.6 MJ/kg digestible energy, 17% crude fibre) completely prevented the disease by inhibiting proliferation of the pathogenic bacteria in the intestine. This protective effect of the diet could not be used for disease control, because the pigs did not develop immunity. A diet moderately low in nutrients (8% crude protein, 9 MJ/kg digestible energy, 11% crude fibre) allowed proliferation of the inoculated bacteria to the point, where most of the pigs developed solid immunity and losses were significantly reduced. This diet combined with inoculation of the pigs with herd specific organisms allowed control of the disease in the field.

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1. A new method of determining dietary metabolisability of energy and digestibility of fatty acids is described. 2. The method requires the digestion of the faecal sample with 4N NC1 and ashing the residue. 3. Comparisons with the "total collection" method that the 4N HC1-insoluble method has similar accuracy.

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