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81.
Macroscopic, histopathologic, and histochemical investigations were made on a group of eight neonatal Angus X Hereford calves, selected from an ongoing outbreak of crooked calf disease among calving heifers. Arthrogryposis of the forelimbs was seen to varying degrees in all eight animals, and torticollis was present in six calves. Histopathology, using hematoxylin and eosin stain, did not reveal any striking or consistent lesion in the affected animals; the majority of the tissues sampled were normal. Muscle samples were processed for adenosine triphosphatase (ATPase) and NADH-tetrazolium reductase (NADH-tr) histochemistry, and the data suggest that a primary myopathy is not responsible for the congenital anomalies in the affected calves. 相似文献
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84.
据欧盟最新的家禽数据显示,虽然欧盟在2009年禽肉产量增长了0.6%,但在2010年预计将下降0.5%.
2009年禽肉进口量和出口量在数量上相差无几,但相关数据表明,如果按价值计算,进口额则显得相对较高,这是因为欧盟出口的禽肉都是低价值的欧盟内部不愿食用的产品,而进口的禽肉绝大部分都是以高于欧盟内部价格进口的高价值的鸡胸肉和火鸡胸肉. 相似文献
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86.
Geun‐Pyo Hong Nicole Avramenko Andrea Stone Dawn Abbott Hank Classen Michael Nickerson 《Cereal Chemistry》2012,89(6):276-283
Extractability and molecular modifications of gliadin and glutenin proteins withdrawn from different stages of a commercial ethanol fuel/distillers dried grains with solubles (DDGS) process using a wheat feedstock were investigated. Materials were taken postliquefaction (PL), postdistillation (whole stillage), and postdrying (DDGS) during the process and then fractionated to separate the gliadins and the soluble high‐ and low‐molecular‐weight glutenins following a modified Verbruggen extraction method. Each fraction was characterized based on the extraction efficiencies within various aqueous alcohols of propan‐1‐ol, electrophoretic patterns, intrinsic and extrinsic fluorescence, free and total sulfhydryl content, and total disulfide bond levels. Findings indicated significant changes to the composition of extracted proteins and modifications to the protein structure (i.e., surface properties and conformation) throughout the ethanol/DDGS process, beginning with the first step of production (PL, ≈83°C). Overall, processing resulted in a shift toward an unextractable gluten matrix, accompanied by increases in hydrophobicity, disulfide bridging, and excessive protein aggregation. 相似文献
87.
Sanjutha Shanmugam Lynette K. Abbott Daniel V. Murphy 《Biology and Fertility of Soils》2014,50(7):1047-1059
The addition of clay to lime-amended biosolids has been proposed as a soil amendment (LaBC®) for remediating acidic-sandy soil. We investigated whether the presence of clay in LaBC® altered soil microbial processes over a 30-week period. Aerobic-incubation and CO2 respiration assays were used to monitor water repellence and chemical and microbiological properties of amended soil. Dry LaBC® was applied at equivalent wet weight of 50, 100 and 150 t ha?1. In addition, dry components of LaBC® (lime, clay, lime + clay (LAC) and lime + biosolids (LAB)) were applied separately at rates equivalent to their fractions within LaBC®. Inclusion of clay in LaBC® was effective in eliminating water repellence at all application rates. Inclusion of clay in LaBC® decreased nitrogen (N) release from the biosolids (by 58 %), even at 50 t ha?1, but only during the first 2 weeks of incubation. LaBC® consistently decreased soil microbial respiration compared with LAB alone when applied at 150 t ha?1 thereby protecting organic matter decomposition. There was no significant N release with lime and clay amendment alone or in combination (LAC) in the absence of the biosolids. There may be a complex interaction between clay, lime and organic matter, but each may have had a role in altering N release from biosolids at different times during the 30-week incubation. Addition of clay to LAB increased its effectiveness in remediating this water-repellent, acidic-sandy soil and prolonged the N release from the biosolids following soil amendment. 相似文献
88.
Erin N. Kishi Shannon P. Holmes Jeffrey R. Abbott Nicholas J. Bacon 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(4):383-388
A 12-year-old dachshund dog was presented for persistent hypercalcemia and hyperparathyroidism despite bilateral parathyroidectomy. Magnetic resonance imaging of the head, neck, and cranial mediastinum identified an increased number of cranial mediastinal lymph nodes with heterogeneous signal intensity. Hypercalcemia and hyperparathyroidism resolved after surgery to remove multiple cranial mediastinal lymph nodes, one of which contained presumed metastatic parathyroid tissue. 相似文献
89.
Biochar is a potential micro-environment for soil microorganisms but evidence to support this suggestion is limited. We explored imaging techniques to visualize and quantify fungal colonization of habitable spaces in a biochar made from a woody feedstock. In addition to characterization of the biochar, it was necessary to optimize preparation and observation methodologies for examining fungal colonization of the biochar. Biochar surfaces and pores were investigated using several microscopy techniques. Biochar particles were compared in soilless media and after deposition in soil. Scanning electron microscopy (SEM) observations and characterization of the biochar demonstrated structural heterogeneity within and among biochar particles. Fungal colonization in and on biochar particles was observed using light, fluorescence and electron microscopy. Fluorescent brightener RR 2200 was more effective than Calcofluor White as a hyphal stain. Biochar retrieved from soil and observed using fluorescence microscopy exhibited distinct hyphal networks on external biochar surfaces. The extent of hyphal colonization of biochar incubated in soil was much less than for biochar artificially inoculated with fungi in a soilless medium. The location of fungal hyphae was more clearly visible using SEM than with fluorescence microscopy. Observations of biochar particles colonized by hyphae from soil posed a range of difficulties including obstruction by the presence of soil particles on biochar surfaces and inside pores. Extensive hyphal colonization of the surface of the biochar in the soilless medium contrasted with limited hyphal colonization of pores within the biochar. Both visualization and quantification of hyphal colonization of surfaces and pores of biochar were restricted by two-dimensional imaging associated with uneven biochar surfaces and variable biochar pore structure. There was very little colonization ofbiochar from hyphae in the agricultural soil used in this study. 相似文献
90.
OBJECTIVES: To compare the family, educational and animal-related backgrounds and career aspirations of students who were selected on the basis of academic criteria with those selected using additional criteria. METHODS: Questionnaires were completed during class time in the first few weeks of enrolment by incoming veterinary students at the University of Sydney, who had been selected on the basis of academic background, and at Charles Sturt University, selected using more broadly-based criteria. The data were transferred to an Excel spreadsheet, and frequency distributions and chi2 statistics estimated using the SAS System for Windows 8. RESULTS: Students selected principally on academic criteria alone had higher average UAI scores, were more likely to have completed high school in a capital city, and to have parents with higher education levels than those selected using additional criteria. Both groups indicated that their choice of veterinary science was based largely on their affinity for animals and keenness to work in a veterinary practice. However, those at CSU placed much greater importance than those at Sydney on a desire to live and work in a rural area, and a desire to help farmers. The broad-based selection methods were the main reasons for students applying to CSU whereas the reputation of the university was the main attraction for Sydney students. Two-thirds of CSU students, but one-third of Sydney students, planned to enter rural mixed practice when they graduated, and most planned to stay for at least 10 years. Conversely, no CSU students, but 42% of those at Sydney, planned to enter small animal practice initially. The percentage planning to work full-time in the first, fifth and tenth year after graduation was not significantly different between the two groups. CONCLUSIONS: Criteria which included actual experience with farm animals have resulted in the selection of more students who plan to enter and remain in rural mixed practice. Further studies over the longer term will be necessary to assess the extent to which these plans are realized. 相似文献