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31.
In terms of animal welfare, farming systems of dairy cows are perceived positively by consumers when compared to pigs or poultry. A main reason is that the majority of consumers associate dairy farming with pasture, which in turn they relate with benefits for animal health and welfare. However, holistic scientific assessments of the effects of pasturing on animal welfare are rare. Hence, it was the aim to study the animal welfare level in 61 German loose housing dairy farms by using the measures of the Welfare Quality® protocol for dairy cattle (WQP). Data were collected twice per farm at the end of the pasture season (July to October) and approximately 6 months later at the end of the barn season (December to April). Farms were classified based on the duration cows had access to pasture per day during the pasture season: group 1 (G1)>10 h; group 2 (G2) 6 to 10 h; group 3 (G3)<6 h and group 4 (G4) without pasture access. The average herd size was 129 Holstein-Friesian or Red-Holstein cows (range 58 to 527). In addition to WQP data, performance data were gathered from routine herd data recordings. The indicators were aggregated to criteria applying the scoring system of the WQP. G4 received lower scores at the first than at the second visit for the criterion absence of hunger, while there were no differences between visits in the other groups (P=0.58 – group×farm visit effect). All pasturing groups were scored better at the end of the pasture season than G4 for the criterion comfort around resting (P<0.01). Compared with G1 for both farm visits and G2 for the end of the barn season, G4 reached inferior scores for the criterion absence of injuries, including indicators such as hairless patches, lesions, and swellings and lameness. At both assessments G2 was scored higher than the other groups for the criterion absence of diseases (P=0.04). In conclusion, pasture access had positive effects only on selected welfare indicators, however, these effects were not maintained throughout the barn season.  相似文献   
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The ability to authenticate the feed given to animals from the animal products has become a major challenge for scientists, monitoring bodies and commercial entities alike. This study compared two methods based on the use of the visible reflectance spectrum of the fat to discriminate pasture-fed (P) from stall concentrate-fed (S) lamb carcasses. A total of 307 (143 P and 164 S) Limousine lambs were used over 2 years. Pasture-fed lambs grazed a permanent pasture that was maintained at a leafy, green vegetative stage, and offered ad libitum; they received no supplementation at pasture. Body weight of P lambs when turning out to pasture and at slaughter averaged 9.2 (standard deviation (s.d.) 2.21) kg and 33.2 (s.d. 2.89) kg, respectively. S lambs were fed indoors on an ad libitum diet of commercial concentrate and hay until slaughter at a mean body weight of 33.7 (s.d. 3.62) kg. The reflectance spectrum of perirenal and subcutaneous caudal fat was measured at slaughter and at 24 h post mortem. Plasma carotenoid concentration was measured at slaughter. In method 1, the fat reflectance spectrum data were used at wavelengths between 450 and 510 nm to calculate an index quantifying light absorption by carotenoid pigments. In method 2, a multivariate analysis was performed over the full set of fat reflectance data at wavelengths between 400 and 700 nm. Method 2 yielded a higher proportion of correctly classified lambs compared with method 1 (P < 0.05 to 0.001), except for measurements made at 24 h post mortem on perirenal fat for S lambs. The proportion of lambs correctly classified using method 2 was 87.4% and 92.9% for measurements made on perirenal and caudal fat at slaughter, and 93.9% and 91.0% for measurements made on perirenal and caudal fat 24 h post mortem. Plasma carotenoid concentrations were higher in P lambs than in S lambs (P < 0.001), which led to correct classification of 90.7% of the lambs.  相似文献   
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Aim We used a landscape‐scale study of birch invasion onto heather moorland to determine the consistency of changes in vegetation type and soil properties and in the community composition of five soil organism groups. Our aim was to determine whether the degree to which soil organisms respond to natural changes and/or induced changes (e.g. changes in land‐use type and climate) in habitat is consistent across trophic and taxonomic groups in the context of conservation policies for birch woodland and heather moorland. Location Mainland Scotland. Methods We sampled mesostigmatid mites, oribatid mites, fungi, bacteria and archaea in adjacent patches of birch woodland (dominated by Betula pubescens) and heather moorland (dominated by Calluna vulgaris) at 12 sites for which annual rainfall ranged between 713 and 2251 mm. Differences in community composition were visualized using non‐metric multidimensional scaling based on Bray–Curtis dissimilarities. The factors contributing to differences between habitats within sites were explored using general linear models and those among sites using redundancy analysis. Results The communities of all groups differed between habitats within sites, but only the oribatid mites and fungi differed consistently between habitats across sites. Within sites, dissimilarity in fungal communities was positively related to the difference in C. vulgaris cover between habitats, whereas dissimilarities in bacteria and archaea were positively related to differences in soil pH and C:N ratio between habitats, respectively. Main conclusions The influence of vegetation type and soil properties differed between groups of soil organisms, albeit in a predictable manner, across the 12 sites. Organisms directly associated with plants (fungi), and organisms with microhabitat and resource preferences (Oribatida) were strongly responsive to changes in habitat type. The response of organisms not directly associated with plants (bacteria, archaea) depended on differences in soil properties, while organisms with less clear microhabitat and resource preferences (Mesostigmata) were not strongly responsive to either vegetation type or soil properties. These results show that it is possible to predict the impact of habitat change on specific soil organisms depending on their ecology. Moreover, the community composition of all groups was related to variation in precipitation within the study area, which shows that external factors, such as those caused by climate change, can have a direct effect on belowground communities.  相似文献   
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The annual activity and spatial distribution of Muscidae and Calliphoridae were investigated in a holm-oak ('dehesa') ecosystem in western Spain over two years in pasture and woodland habitats, using wind-orientated traps baited with a mixture of fresh cattle faeces, liver and sodium sulphide solution. Lucilia sericata (Meigen) was always the dominant species and, with Chrysomya albiceps (Weidemann), Hydrotaea ignava (Harris), Muscina levida (Harris) and Muscina prolapsa (Harris), was more abundant during the second than the first year. By contrast, Calliphora vicina Robineau-Desvoidy, Calliphora vomitoria (L.), Hydrotaea armipes (Fallén), Hydrotaea penicillata (Rondani) and Hydrotaea dentipes (Fabricius) were more numerous during the first than the second year of the study. In summer, the Diptera sampled were significantly more abundant in a wooded than a pasture area. However, in autumn, while H. penicillata remained significantly more abundant in woodland, L. sericata became more abundant in the pasture, whereas C. vicina was captured in open and wooded areas in similar proportions. During winter and spring the populations sampled were relatively small. The changing patterns of abundance are discussed in relation to differences in climate within and between years.  相似文献   
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Ellis  S.  Yamulki  S.  Dixon  E.  Harrison  R.  Jarvis  S.C. 《Plant and Soil》1998,202(1):15-25
Total denitrification and nitrous oxide (N2O) losses were measured from three contrasting dairy management systems representing good commercial practice (system 1), production maintained but with reduced N losses (system 2); and nitrate leaching less than 50 mg L-1 but with reduced production (system 3). Measurements were made following mineral fertiliser application and from two plot experiments where four treatments were applied: control, NH4NO3 at 60 kg N ha-1, cattle slurry applied to the surface (equivalent to 45 kg N ha-1), and cattle slurry injected. Despite low soil temperatures (<6 °C) and low rainfall (<3 mm), total denitrification and N2O losses peaked at 56 and 16 g N ha-1 d-1, respectively. Total denitrification losses decreased: system 1 system 2 > system 3, whereas N2O losses decreased: system 2 > system 3 > system 1. Total denitrification losses tended to decrease with decreasing fertiliser application rate, whereas fertiliser application rate was not the sole determinant of the N2O loss. The system 3 field was injected with cattle slurry for 2 yr, system 2 received some slurry by injection and system 1 received slurry to the surface. Thus, the amount, timing and method of previous cattle slurry application was important in determining the loss following subsequent fertiliser application. For the plot experiments, total denitrification and N2O losses decreased in the order: slurry injected > mineral fertiliser > slurry applied to the surface > control for 5 days following application. However, 16 and 19 days after application, N2O losses above the control were measured from plots that had received cattle slurry. It was inferred that the application of cattle slurry to the pasture soil stimulated greater N2O production and increased losses over a longer time period compared with mineral fertiliser additions.  相似文献   
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The conversion of two‐thirds of New Zealand's native forests and grasslands to agriculture has followed trends in other developed nations, except that pastoral grazing rather than cropping dominates agriculture. The initial conversion of land to pasture decreased soil acidity and elevated N and P stocks, but caused little change in soil organic C stocks. However, less is known about C and nutrient stock changes during the last two decades under long‐term pastoral management. We resampled 31 whole soil profiles in pastures spanning seven soil orders with a latitudinal range of 36–46°S, which had originally been sampled 17–30 years ago. We measured total C, total N, and bulk density for each horizon (generally to 1 m) and also reanalyzed archived soil samples of the same horizons for C and N. On average, profiles had lost significant amounts of C (− 2.1 kg C m−2) and N (− 0.18 kg N m−2) since initial sampling. Assuming a continuous linear decline in organic matter between sampling dates, significant losses averaged 106 g C m−2 yr−1 (P=0.01) and 9.1 g N m−2 yr−1 (P=0.002). Removal of C through leaching and erosion appears too small to explain these losses, suggesting losses from respiration exceed the inputs of photosynthate in the soil profile. These results emphasize that resampling soil profiles provide a robust method for detecting soil C changes, and add credence to the suggestion that soil C losses may be occurring in some temperate soil profiles. Further work is required to determine whether these losses are continuing and how losses might be extrapolated across landscapes to determine the implications for New Zealand's national CO2 emissions and the sustainability of the implied rates of soil N loss.  相似文献   
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Aims:  To assess the bacterial biodiversity level in bovine raw milk used to produce Fontina, a Protected Designation of Origin cheese manufactured at high-altitude pastures and in valleys of Valle d'Aosta region (North-western Italian Alps) without any starters. To study the relation between microbial composition and pasture altitude, in order to distinguish high-altitude milk against valley and lowland milk.
Methods and Results:  The microflora from milks sampled at different alpine pasture, valley and lowland farms were fingerprinted by PCR of the 16S–23S intergenic transcribed spacers (ITS-PCR). The resulting band patterns were analysed by generalized multivariate statistical techniques to handle discrete (band presence–absence) and continuous (altitude) information. The fingerprints featured numerous bands and marked variability indicating complex, differentiated bacterial communities. Alpine pasture milks were distinguished from lowland ones by cluster analysis, while this technique less clearly discriminated alpine pasture and valley samples. Generalized principal component analysis and clustering-after-ordination enabled a more effective distinction of alpine pasture, valley and lowland samples.
Conclusions:  Alpine raw milks for Fontina production contain highly diverse bacterial communities, the composition of which is related to the altitude of the pasture where milk was produced.
Significance and Impact of the Study:  This research may provide analytical support to the important issue represented by the authentication of the geographical origin of alpine milk productions.  相似文献   
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