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Quantitative study of the α-and γ-tocopherols accumulation in muscle and backfat from Iberian pigs kept free-range as affected by time of freerange feeding or weight gain AbstractThe experiment was undertaken to quantify the a and g-tocopherols accumulation in muscle and backfat from Iberian pigs given food free-range as affected by the time of free-range feeding or the weight gained during the fattening in free-range. Pigs were given their food in a free-range production system with pasture and acorns (Quercus rotundifolia) for different periods of time: 46 days (free-range 3), 83 days (free-range 2) and 111 days (free-range 1). A control was given food free-range for 0 days. In addition another experiment was developed to determinate the effect of the the weight gained on the tocopherols accumulation at a similar period of time (111 days) given food free-range: one group gained 68·7 kg of weight (free-range A) and the other 43·6 kg (free-range B). The concentration of g-tocopherol significantly ( P , 0·0001) increased after 83 days of feeding in the longissimus dorsi (LD) and biceps femoris (BF) muscles, and after 111 days in the inner and outer backfat layers. The concentration of a-tocopherol was not statistically affected by the days of free-range feeding in any case. Iberian pigs that put on more weight had significantly ( P , 0·0001) higher concentration of a and g-tocopherols in the inner and outer backfat layers, and a-tocopherol in the BF muscle than those given food free-range B. However, no differences were detected in the proportion of a-tocopherol in the LD and g-tocopherol in the LD and BF. The g-tocopherol content of LD and BF muscles depending on the days of feeding were adjusted to linear and quadratic regressions ( R 2 ¼ 0·8705 and 0·8697, respectively), while the outer and inner backfat layers were linear equations ( R 2 ¼ 0·8480 and 0·8119, respectively). However, the g-tocopherol concentration as affected by the weight gained in free-range showed in all tissues a linear and a quadratic trend that were adjusted to exponential responses. The a-tocopherol content was affected by the g-tocopherol concentration in muscle and outer backfat layer. The tocopherol concentration (a and g-tocopherols) in the backfat layers may discriminate better between the pigs of high quality that were given food free-range for a long period of time and those that stayed an intermediate period. However, to discriminate between the pigs on formulated food and those given food free-range, the quantification of the g-tocopherol concentration in muscle could be a better indicator.

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~~~ ~Streptomyces griseus ATCC 10137, S . griseus IMRU 3570, S. griseus JI 2212, S. acrimycini JI 2236 and S. albus G sporulated abundantly in several liquid media after nutritional downshift. Spores formed in submerged cultures were viable and as thermoresistant as aerial spores. Scanning electron microscopy showed that submerged spores are morphologically similar to aerial spores. The sporulation of the Streptomyces strains tested in complex medium appeared to be triggered by phosphate nutritional downshift, induced by addition of Ca2+ to the medium. Spore-shaped bodies were formed by S. lividans JI 1326 and S. coelicolor JI 2280 when grown in complex medium supplemented with Ca2+ and proline. The thermoresistance of these spore-shaped bodies differed from that of aerial spores.