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The cDNAs of two turkey cytokines, interleukin (IL)-10 and IL-13, were cloned using oligonucleotide primers designed from their chicken orthologues. The coding regions of the chicken and turkey genes are highly conserved, with IL-10 and IL-13 exhibiting 94.1% and 90% nucleotide and 92% and 79.9% amino acid identity respectively. Both showed consistent mRNA expression in turkey lymphoid and gut tissues. Expression in non-lymphoid tissues was more variable but generally highest in the skin and trachea. Recombinant turkey IL-10 was expressed and bioactivity demonstrated by inhibition of IFN-γ synthesis from activated splenocytes. Chicken and turkey IL-10 cross-reacted in functional assays.  相似文献   
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Nine mature horses were used to evaluate superoxide dismutase (SOD) response to a low-intensity standard exercise test and the effect of copper (Cu) and zinc (Zn) supplement form on enzyme activity. The modified switchback experiment was conducted over seven 28-day periods. Horses were conditioned to perform an average daily workload of 3.93 kg∗km∗10−3 with a digestible energy (DE) demand of approximately 29 Mcal. Following a controlled Cu and Zn repletion-depletion diet sequence, horses were fed a diet intended to be marginally deficient in Cu and Zn with the minerals supplemented in either sulfate or organic chelate forms. Horses were then subjected to a standardized exercise test to enable evaluation of SOD activity during exercise and immediate recovery. In the final analyses, mineral contents of the experimental diets were significantly different (P < .05). The mean mineral concentration of the sulfate diet was 6.28 ppm Cu and 35.99 ppm Zn, while the chelate diet contained 23.62 ppm Cu and 90.67 ppm Zn. Even so, resting SOD activity was not altered by diet (1793.47 ± 323.00 U/g Hb for the sulfate diet, 1355.70 ± 148.32 U/g Hb for the organic-chelate diet), nor did SOD activity change in response to the low-intensity workout. The SOD activity was unchanged by feeding a Cu and Zn supplemented diet to horses fed to be in a mineral-deficient state. These exercise bouts did not appear to have a significant impact on SOD activity. Other types of oxidative stress should be considered when trying to evaluate the antioxidant responsiveness of this enzyme.  相似文献   
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This study was to evaluate the effect of xylanase supplementation and the addition of live yeast, Saccharomyces cerevisiae, on growth performance and intestinal microbiota in piglets. One hundred and eighty commercial crossbred 23-d-old piglets (PIC 417) were sorted by initial BW and allocated to 3 treatments: control (CTR) diet, CTR diet supplemented with xylanase at 16,000 birch xylan units/kg (XYL) and XYL diet supplemented with live yeast (2 × 1010 CFU/g) at 1 kg/t (XYL + LY). Each treatment had 10 replicates, with 6 animals each. A sorghum-based diet and water were available ad libitum for 42 d of the study. Average daily gain (ADG) and average daily feed intake (ADFI) were measured from 0 to 42 d (23- to 65-d-old) and feed conversion ratio (FCR) calculated. At the end of the study, bacterial identification through 16S rRNA (V3 to V4) sequencing of the ileal and caecal digesta from one piglet per replicate was performed. No treatment effects were observed on ADFI. Pigs offered the live yeast in addition to the xylanase had increased ADG compared with those supplemented with xylanase alone (XYL + LY vs. XYL; P = 0.655). FCR was improved with XYL and XYL + LY compared with CTR (P = 0.018). Clostridiaceae counts in the ileum tended to reduce by 10% with XYL and 14% with XYL + LY compared to CTR (P = 0.07). XYL and XYL + LY increased the counts of Lactobacillaceae in the caecum compared with CTR (P < 0.0001). Dietary supplementation of live yeast combined with xylanase improved growth performance and microbial balance of piglets during the nursery phase.  相似文献   
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Newcastle disease (ND) is a highly contagious avian disease and one of the major causes of economic losses in the poultry industry. The emergence of virulent NDV genotypes and repeated outbreaks of NDV in vaccinated chickens have raised the need for fundamental studies on the virus–host interactions. In this study, the profiles of B and T lymphocytes and macrophages and differential expression of 26 immune-related genes in the spleen of specific-pathogen-free (SPF) chickens, infected with either the velogenic genotype VII NDV strain IBS002 or the genotype VIII NDV strain AF2240, were evaluated. A significant reduction in T lymphocyte population and an increase in the infiltration of IgM+ B cells and KUL01+ macrophages were detected in the infected spleens at 1, 3 and 4 days post-infection (dpi) (P < 0.05). The gene expression profiles showed an up-regulation of CCLi3, CXCLi1, CXCLi2 (IL-8), IFN-γ, IL-12α, IL-18, IL-1β, IL-6, iNOS, TLR7, MHCI, IL-17F and TNFSF13B (P < 0.05). However, these two genotypes showed different cytokine expression patterns and viral load. IBS002 showed higher viral load than AF2240 in spleen at 3 and 4 dpi and caused a more rapid up-regulation of CXCLi2, IFN-γ, IL-12α, IL-18, IL-1β, iNOS and IL-10 at 3 dpi. Meanwhile, the expression levels of CCLI3, CXCLi1, IFN-γ, IL-12α, IL-1β and iNOS genes were significantly higher in AF2240 at 4 dpi. In addition, the expression levels of IL-10 were significantly higher in the IBS002-infected chickens at 3 and 4 dpi. Hence, infection with velogenic genotype VII and VIII NDV induced different viral load and production of cytokines and chemokines associated with inflammatory reactions.  相似文献   
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Ecosystem service supply and vulnerability to global change in Europe   总被引:12,自引:0,他引:12  
Global change will alter the supply of ecosystem services that are vital for human well-being. To investigate ecosystem service supply during the 21st century, we used a range of ecosystem models and scenarios of climate and land-use change to conduct a Europe-wide assessment. Large changes in climate and land use typically resulted in large changes in ecosystem service supply. Some of these trends may be positive (for example, increases in forest area and productivity) or offer opportunities (for example, "surplus land" for agricultural extensification and bioenergy production). However, many changes increase vulnerability as a result of a decreasing supply of ecosystem services (for example, declining soil fertility, declining water availability, increasing risk of forest fires), especially in the Mediterranean and mountain regions.  相似文献   
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The scaling up of processes in the plant–soil–microbe system represents one of the greatest challenges facing environmental scientists and yet is essential for sustainable land management worldwide. The latter encompasses, for example, the mitigation of and adaptation to anthropogenic climate change, the bioremediation of industrially contaminated sites, catchment management of human pathogens such as Escherichia coli O157 and integrated crop management on the farm. Scaling up is also essential for the regional and global biogeochemical modelling that will inform policy-makers of the critical environmental factors driving climate change. Despite increasing understanding of the links between gene expression and process on a microscale, there is still much progress to be made when relating this to processes at the macroscale. In this paper, we explore the challenges this poses and examine key case studies of successful up-scaling.
Dominic StandingEmail:
  相似文献   
40.
A specific method of rehabilitation was used to manage obese horses with laminitis, and clinical outcome was evaluated after 5 to 20 months. Clinical data from 14 similar laminitis cases were statistically analyzed to evaluate response to rehabilitation. Data were analyzed using repeated measures or logistic regression methodologies. Each horse presented as obese and laminitic with no history of a systemic inflammatory disease. The rehabilitation method emphasized a mineral-balanced, low nonstructural carbohydrate diet; daily exercise; hoof trimming that minimized hoof wall loading; and sole protection in the form of rubber hoof boots and/or hoof casts. Distal phalanx alignment within the hoof capsule was significantly improved, and hoof wall thickness was significantly decreased (P < .0001) following treatment. Solar depth was significantly increased (P < .0015). Reduction of palmar angle measurements was detected in acutely and chronically affected horses. This treatment effect was statistically greater for horses with chronic laminitis than for horses with acute laminitis (P interaction < .0001). Horses were 5.5 times more likely to be sound post-treatment than before treatment. Daily exercise, dietary modification, and removal of ground reaction force from the hoof wall were foci of the rehabilitation program. Hoof care and husbandry as applied to these horses may be an effective method of rehabilitation of horses from obesity-associated laminitis.  相似文献   
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