Performance,carcass and technological meat quality of pigs in indoor and outdoor production systems

Abstract

This study aimed to compare different production systems, i.e., the combined effect of outdoor and indoor rearing of pigs and organic diets fed ad libitum or restrictively. Furthermore, the suitability of two breed crosses for outdoor rearing was studied. The effects on performance, carcass and technological quality traits were investigated. During two years, 240 pigs of Duroc x Large White (D*LW) and Swedish Landrace x Large White (L*LW) were allocated to three production systems: 1) Pigs kept outdoors, fed an organic diluted diet (20% alfalfa roughage) ad libitum; 2) Pigs kept outdoors, strategically fed a diluted organic diet up to a live weight of approximately 80 kg and thereafter an undiluted organic diet ad libitum; 3) Pigs kept indoors, fed an undiluted organic diet restrictively. For outdoor pigs, strategic feeding increased daily weight gain and backfat thickness, compared with feeding a diluted diet throughout (p≤0.01). L*LW pigs in both outdoor systems grew slower than in the indoor system (p≤0.001), whereas for D*LW pigs only outdoor pigs fed the diluted diet had a slower growth rate. Outdoor pigs had lower dressing percentage than indoor pigs. Glycogen content and L* values in M. longissimus dorsi were higher, whereas b* values were lower in meat from pigs in the indoor system. D*LW pigs had higher water-holding capacity (lower drip, thawing and cooking losses), lower shear force and higher intramuscular fat content compared with L*LW pigs.     

Aggressive and sexual behaviour of growing and finishing pigs reared in groups,without castration

Abstract

Aggressive and sexual behaviour in entire males and females were studied on 408 pigs. The sum of aggressive interactions in the pen during routine feeding (ALP) was lowest in single-sex pens with females. ALP was higher at 132 than at 155 days. High ALP correlated with high average growth rate. Aggressive interactions in a competition test (IA) increased after slaughter of the three fastest-growing pigs in a pen (at 155 days), although the slaughtered pigs had initiated the most IA earlier (at 132 days). Entire male pigs displayed more sexual behaviour (mounting) than females. In 15% of entire males and 6% of females there were health problems specifically involving lameness or injured legs or feet. Five entire males and one female were euthanized in response to lameness or leg fracture. The rearing of entire male pigs may cause welfare problems, given their higher levels of aggression and sexual behaviour.     

Moss-Erwinia pathosystem reveals possible similarities in pathogenesis and pathogen defense in vascular and nonvascular plants

Vascular plants have various inducible resistance mechanisms as defense against pathogens. Mosses, small nonvascular plants (subkingdom Bryophyta), have been little studied in regard to their pathogens or modes of defense. Data here show that Erwinia carotovora, a bacterial plant pathogen that causes softrot in many dicotyledonous plants, can also cause soft rot symptoms in the moss Physcomitrella patens. Infection of moss by E. carotovora required pathogenicity factors similar to those required to infect vascular plants and, again as in vascular plants, salicylic acid (SA) induced moss to inhibit tissue maceration by Erwinia. These data reveal that SA-dependent defense pathways may have evolved before differentiation of vascular and nonvascular plants.     

Modelling the sprouting capacity from underground buds of the perennial weed Sonchus arvensis

Sonchus arvensis is a problematic perennial weed species causing problems in many crops. Control measures often rely on soil tillage or mowing; both methods are used to exhaust the root system. This approach fails during periods of restrictions in sprouting capacity or shoot regrowth. The aim of this study was to develop a simulation model for prediction of shoot sprouting capacity in underground buds of S. arvensis. We hypothesised restricted regrowth to be induced as a function of photoperiod and temperature sum and released as a function of cold temperature sum. The model was parameterised and calibrated against observations of shoot regrowth from an experiment on intact roots of S. arvensis. Subsequently, it was validated against observations of regrowth from another experiment on intact roots and sprouting from fragmented roots from a third experiment. Restriction in regrowth was attributed to reduction in the photoperiod, observed when the day length decreased below a threshold of 16.5 h, but also to a daily mean temperature below 16.8°C. Resumed regrowth occurred in late autumn at a daily mean temperature threshold of 4.7°C. The pattern of changes over time in shoot regrowth from an intact root system was well predicted by the model. The temporal change in sprouting capacity from buds on fragmented roots followed the same pattern, but with a quantitative difference between the model prediction and the observed sprouting capacity. We conclude that the model can be used to predict the pattern over time of sprouting capacity in intact roots of S. arvensis.     

Application of Relaxed Eddy Accumulation Technique to Quantify Hg0 Fluxes Over Modified Soil Surfaces

Fluxes of mercury from a waste repository and from an agricultural field amended with sewage sludge were measured. The measurements were performed by utilising a Relaxed Eddy Accumulation (REA) system synchronously coupled to automated mercury cold vapour atomic fluorescence analysers (CVAFA). The waste repository was severely contaminated and fluxes of between 0.16μg m^?2 h^?1 and 29μg m^?2 h^?1 could be measured. Fluxes at the slightly contaminated agricultural field measured between 8 ng m^?2 h^?1 and 1.9μg m^?2 h^?1. The results showed that the REA-CVAFA system could be used for measurements above both severely-and slightly contaminated soils. The measurements at the chlor-alkali plant showed that temperature was the most important parameter controlling the release of mercury at this site. At the agricultural field, the measurements indicated that both solar radiation and temperature may have influenced the emissions. Most of the mercury added to the field was lost to the atmosphere during the summer season.     

Effects of liming on carbon and nitrogen mineralization in coniferous forests

A temporary decline in tree growth has often been observed after liming in coniferous forests poor in N but seldom in forests rich in N. To test the hypothesis that the decline was caused by decreases in N supply, C and N mineralization were estimated in incubated soil: (1) after liming in the laboratory, and (2) after earlier liming in the field. Liming increased the C mineralization rate in needle litter, mor humus and 0 to 5 cm mineral soil for a period of 40 to 100 days at 15°C. After that period, liming had no effect on the CO₂ evolution rate in materials poor in N (C:N ratios 30 to 62) but increased the CO₂ evolution rate in materials rich in N (C:N ratios 24 to 28). When liming induced nitrification, the CO₂ evolution rate was reduced. Liming resulted in lower net N mineralization rate in needle litter and mor humus. The reduction was more pronounced when NH ₄ ⁺ was the only inorganic form than when NO ₃ ^? was the predominant form. The reason is probably that chemical fixation of NH₃ and amino compounds increases with increasing pH. Because of the fixation, the incubation technique most likely underestimated the mineralized N available to the roots. Taking this underestimation into consideration, liming initially reduced the N release in the litter layer. In the other soil layers, liming increased the N release in soils rich in N and had only small effects in soils poor in N. For the total N supply to the roots in the litter, humus and 0 to 5 cm mineral soil layers, liming caused a slight reduction in soils poor in N and a slight increase in soils rich in N. Data on tree growth corresponded with these results. The hypotheses that tree growth depressions can be caused by reduced N supply after liming and that tree growth increases can be caused by increased N supply after liming thus seem reasonable.     

Competitive adsorption of water soluble plasma proteins from egg yolk at the oil/water interface

Water soluble plasma proteins were fractionated from hen's egg yolk, and the molecular weight and pI of the most abundant protein species were characterized with gel electrophoresis. The proteins were identified by mass spectrometry. The protein fraction was used to produce oil-in-water emulsions, both at various protein concentrations and at various pH values, and the surface load was determined through serum depletion. The competitive adsorption was studied through the determination of nonadsorbing species with gel electrophoresis. The results show that it was possible to form an oil-in-water emulsion for which droplet size and maximum surface load depended on the protein concentration and pH. Serum albumin and YGP40 adsorbed selectively at the oil/water interface throughout the pH range investigated, and for albumin the selectivity increased close to its pI. It is suggested that this selective adsorption is due to long hydrophobic stretches in the polypeptide chain, which are present in the selectively adsorbing species but absent in less adsorbing species.     

Chromosome Y-specific DNA is transferred to the short arm of X chromosome in human XX males

Y-chromosomal DNA is present in the genomes of most human XX males. In these cases, maleness is probably due to the presence of the Y-encoded testis-determining factor (TDF). By means of in situ hybridization of a probe (pDP105) detecting Y-specific DNA to metaphases from three XX males, it was demonstrated that the Y DNA is located on the tip of the short arm of an X chromosome. This finding supports the hypothesis that XX maleness is frequently the result of transfer of Y DNA, including TDF, to a paternally derived X chromosome.