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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.

Mediterranean dehesas are an archetypal example of high nature value farmland in Europe. To better understand the interactions between trees and grasslands in the conservation and management of the dehesa, we measured, over 3 years, the contribution of scattered trees to the diversity and biomass dry-matter (DM) yield of the herb layer and the relationship between the herb layer (biomass and diversity interaction) and the trees. The study was based on 135 subplots representing four aspects and three distances from fifteen trees selected randomly in a plot within a dehesa in central Spain. The specific questions were the following: (i) To what extent do trees affect biomass of the herbaceous layer? (ii) What is the relationship between herbaceous layer biomass and species diversity under the influence of trees? and (iii) What are the effects of trees and small-scale topography on the herbaceous diversity? Results differed between years depending on water availability. Legume and forb DM yields were highest at the edge of the tree crown and beyond the canopy. Species richness was positively related to legume DM yield, and both were higher at the bottom of the hillside, especially in dry conditions. Given the importance of tree influence on the biomass and diversity of grasslands, maintaining proper agroforestry management practices for trees and grasslands is important for conserving dehesa diversity and productivity under the conditions of high climatic and soil variability in Mediterranean dehesas.

The effect of gender (entire males vs females) on growth performance, carcass traits and meat and fat quality of Avileña-Negra Ibérica calves, fattened under free range conditions and supplemented with concentrate, were investigated. The average daily gain, leg width and thorax depth were higher in males than in females. Carcass conformation score, fore-quarter weight and percentage in carcass were higher in males than in females, whereas dressing percentege, loins and flank percentages in carcass and carcass fatness degree were higher in females than in males. Instrumental colour variables of muscle were not affected by gender at days 1, 3, 7 and 9 of refrigerated storage. In muscle, the L * , a * , b * , chroma, oxymyoglobine and oxymyoglobine/metmyoglobine ratio values observed 9 days after slaughter were lower than those at days 1 and 3 after slaughter. Intramuscular fat percentage of Longissimus thoracis muscle was higher in females than in males. Gender had no effect on α-tocopherol content in intramuscular fat (IMF) from Longissimus thoracis muscle. The omental and IMF of females had lower C18:2 n-6, Σ n-6 and Σ PUFA proportions than those from the males. In IMF C16:1, C18:1 n-9 and Σ MUFA proportions were greater in females than in males. The IMF percentage in Longissimus thoracis affected significantly to its fatty acid composition.

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The main objective of this experiment was to asses the effect of acorn size consumed during the fattening period (90.1-137.9 kg) on growth performance, carcass characteristics and fat quality from Iberian pigs. Two groups of eight barrows were located in individual cages and fed ad libitum with acorns in confinement. One group of pigs received acorns of large size (average weight 4.26 g) and the other one acorns of small size (2.49 g). The pigs that received small acorns had lower average daily intake (5.5 kg) than those pigs given large acorns (5.7 kg) and consequently, weight average daily gain and carcass weight were significantly lower (0.7 vs 0.6 kg and 111.1 vs 106.2 kg respectively). The acorn size had not significant influence on major fatty acids proportions contained in subcutaneous fat and intramuscular Longissimus dorsi muscle.

Dehesas or montados are man-made systems whose conservation interest as a Mediterranean landscape or agroforestry system has been highlighted in the scientific literature due to their high levels of biodiversity. The understanding of how management practices influence the biodiversity of the dehesa requires a comprehensive approach that considers the broad spectrum of biological components (i.e., fungi, lichens, vascular plants, macroinvertebrates, and vertebrates) that make the dehesa an ecosystem. We have reviewed around seventy publications compiled through Scopus and other specialized bibliographic sources not included in Scopus that study the impact of land use and land cover on the biodiversity of Iberian dehesas. The most significant results have been organized and summarized into a group of factors related to habitat structure and management practices. The conclusion to be drawn from the scientific studies is that not all biological components respond in the same way to land-cover and human practices, and the maintenance of a high overall diversity in dehesas depends on a complex understorey vegetation and habitat heterogeneity.

The effect of feeding system (calves reared under free-range conditions supplemented with concentrate vs. calves fed on concentrate and cereal straw in confinement) during finishing period on growth performance, carcass traits and meat and fat quality was investigated. Fourteen entire males of Avileña-Negra Ibérica breed were used. The feeding system had no effect on growth performance, carcass characteristics, muscle colour, drip losses and intramuscular fat (IMF) percentage in Longissimus thoracis. Free-range calves had more content of vitamin E in omental fat and tended (p < 0.1) to have more vitamin E in IMF than calves finished in confinement. C16:0 and C16:1 n-9 proportions in omental fat were higher in calves finished in confinement, while C18:1 n-7, C18:3 n-3, Σn-3 proportions were lower. The ratio Σpolyunsaturated fatty acids (PUFA) to Σsaturated fatty acids (SFA) was significantly greater in omental fat from free-range calves. The C14:0, C16:0, C16:1, C17:0, C17:1, C18:1 n-9 and Σmonounsaturated fatty acids (MUFA) were higher and C18:3 n-3 and Σn-3 proportions lower in IMF from calves finished in confinement. The ratio C18:1 n-9 to C18:0 was higher in IMF from calves fed on concentrate and straw and the ratio ΣPUFA to ΣSFA tended (p < 0.1) to be greater in free-range calves. Intramuscular fat percentage affected to fatty acid composition of Longissimus thoracis. Feeding system based in finishing calves in confinement with straw and concentrate can be replaced by supplementation with concentrate in grazing without detrimental effect on quality.