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11.
This study was conducted to study absorption of glucosamine (GlucN) and chondroitin sulfate (CS) in horses immediately after feeding. Six mature mares were used in a replicated 3 × 3 Latin-square-designed experiment. The experiment consisted of three 15-day periods, which included 10 days of diet adaptation followed by a 5-day sampling period. Blood was drawn after feeding on one day during each sampling period. Horses were fed a control diet (40% hay, 60% concentrate) balanced to meet NRC requirements for maintenance of mature horses (NRC, Nutrient requirements of horses, 1989). In one experimental diet, 2.0 g CS and 5.5 g GlucN were added to the basal ration at each feeding. In the other experimental diet, 3.5 g CS and 8.5 g GlucN were added to the basal ration at each feeding. After collections, blood was centrifuged and plasma was harvested and stored until analyzed for the presence of each compound. Analyses for plasma GlucN were performed using high-performance liquid chromatography. CS in the plasma was analyzed using a color reagent, dimethylmethylene blue, followed by ultraviolet spectrophotometry. There were no significant differences (P < .05) in the concentration of either CS or GlucN in plasma, when comparing the three different diets. This leads to a conclusion that these compounds were not absorbed intact through the intestinal wall into the bloodstream. This poses a question as to whether oral forms of these compounds are absorbed and are able to migrate to joints through the blood to improve joint function.  相似文献   
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Plants link atmospheric and soil carbon pools through CO2 fixation, carbon translocation, respiration and rhizodeposition. Within soil, microbial communities both mediate carbon-sequestration and return to the atmosphere through respiration. The balance of microbial use of plant-derived and soil organic matter (SOM) carbon sources and the influence of plant-derived inputs on microbial activity are key determinants of soil carbon-balance, but are difficult to quantify. In this study we applied continuous 13C-labelling to soil-grown Lolium perenne, imposing atmospheric CO2 concentrations and nutrient additions as experimental treatments. The relative use of plant- and SOM-carbon by microbial communities was quantified by compound-specific 13C-analysis of phospholipid fatty acids (PLFAs). An isotopic mass-balance approach was applied to partition the substrate sources to soil respiration (i.e. plant- and SOM-derived), allowing direct quantification of SOM-mineralisation. Increased CO2 concentration and nutrient amendment each increased plant growth and rhizodeposition, but did not greatly alter microbial substrate use in soil. However, the increased root growth and rhizosphere volume with elevated CO2 and nutrient amendment resulted in increased rates of SOM-mineralisation per experimental unit. As rhizosphere microbial communities utilise both plant- and SOM C-sources, the results demonstrate that plant-induced priming of SOM-mineralisation can be driven by factors increasing plant growth. That the balance of microbial C-use was not affected on a specific basis may suggest that the treatments did not affect soil C-balance in this study.  相似文献   
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Previous studies using F1 reciprocal crosses and two parental lines of broilers show the sire is instrumental in determining the in vitro leukocyte function and cytokine/chemokine profile. Since the innate immune response is the primary means young chickens have to protect themselves, we hypothesize utilizing a novel genomics approach to select sires based on an elevated pro-inflammatory cytokine and chemokine profile. By identifying sires with increased pro-inflammatory cytokine (interleukin [IL]-1beta and IL-6) and chemokine (CXCLi2 and CCLi2) mRNA expression levels, we expect the progeny will also have elevated profiles. We characterized the pro-inflammatory cytokine and chemokine profile of 119 sires using quantitative real-time RT-PCR (qRT-PCR) and identified two populations with inherently high and low mRNA expression levels of IL-1beta, IL-6, CXCLi2, and CCLi2. Select high and low sires were then used to produce progeny for the second phase of the trial. Blood samples were collected from 214 progeny and the cytokine and chemokine mRNA expression levels determined. Progeny from high sires had significantly (P相似文献   
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Birds are continuously confronted by a large number of stressors, including pathogens. Despite their variety, all stressors induce an elevation in plasma corticosterone concentration, and consequently increase heterophil to leukocyte (H/L) ratio. In order to evaluate and differentiate effects of endocrine (non-bacterial) and bacterial stress on the proportions and ultrastructural characteristics of chicken leukocytes, a series of experiments were conducted with seven-week old chickens exposed either to dietary corticosterone or to intravenous (i.v.)-injected lipopolysaccharide (LPS). Samples were taken for haematological, endocrine, and electron microscopy examination. Administration of corticosterone and LPS significantly elevated plasma corticosterone concentrations and increased H/L ratios. Electron microscopy observations indicated changes in heterophil size, shape, and granulation, and lymphocyte cytoplasmic characteristics. Immature heterophils were observed in the peripheral blood, suggesting that corticosterone and LPS both stimulate an earlier release of heterophils from bone marrow and enhance their influx into blood circulation. The LPS induced a degenerative morphology and the destruction of lymphocytes, whereas corticosterone appeared to stimulate their redistribution rather than destruction. The results indicate that exposure to corticosterone or LPS similarly increase H/L ratios, but differentially alter the ultrastructure of heterophils and lymphocytes. Elucidation of the mechanisms that cause such changes may play an important role in distinguishing between a nonimmune and immune stress challenge at the molecular level.  相似文献   
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Scarcity of water and emission of greenhouse gases (GHGs) are the two key environmental issues affecting crop production in India.Reducing the carbon footprint (CF) and water footprint (WF) of crop production can help to mitigate the environmental hazards that stem from GHG emissions and water scarcity.The CFs and WFs of three major cereal crops,rice,wheat,and maize,were estimated for the year 2014 under the environmental conditions in India,based on national statistics and other data sources.To...  相似文献   
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A 3‐month‐old female Basset Hound‐Shar Pei mix puppy (Ba‐Shar or Sharp Asset) presented with oral bleeding due to a cracked molar. On physical exam, an aural hematoma was also noted that the owner indicated was chronic. The puppy was hospitalized for over 24 h until the bleeding was brought under control. At 4 months of age, the puppy again presented with oral bleeding due to loss of deciduous teeth and was hospitalized until bleeding was controlled. Coagulation screening tests, platelet numbers, and von Willebrand Factor antigen levels were within reference limits. Based on the presence of platelet‐type bleeding in the face of normal screening test results, samples were submitted for DNA testing for Basset Hound thrombopathia. The puppy tested as affected for the calcium and diacylglycerol regulated guanine nucleotide exchange factor I (CalDAG‐GEFI) mutation causing this disorder. This is the first time thrombopathia has been diagnosed in a “designer” breed.  相似文献   
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