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A 2 yr old dog presented for dysphagia and coughing secondary to a 4 cm × 4 cm turgid subepiglottic mass. Cervical radiographs, an esophagram, and computed tomography confirmed the presence of a cystic mass that was not intimately associated with any surrounding structures. An incisional biopsy confirmed the cystic nature of the mass and helped to rule out a malignancy. A marginal surgical excision was performed via a ventral approach. Histopathology of the mass was consistent with a thyroglossal duct cyst. This is the first report of a thyroglossal duct cyst in this location in a dog. There was no recurrence of clinical signs 14 mo after surgery.  相似文献   
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A 7 yr old spayed female mastiff presented for examination of a left pelvic limb lameness of 3 mo duration. Six years previously, the dog had undergone tibial plateau leveling osteotomy (TPLO) surgery of the left pelvic limb for the treatment of cranial cruciate disease. On presentation, the dog had a painful and swollen proximal tibia. Following investigation, a diagnosis of osteosarcoma of the proximal left tibia at the site of the previous TPLO surgery was made. This is the first reported case of osteosarcoma following TPLO using an implant other than the Slocum plate.  相似文献   
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An antemortem diagnosis of disseminated hemangiosarcoma with extensive hepatic and splenic involvement was made in a 9-year-old cow evaluated for lethargy, weight loss, regenerative anemia, thrombocytopenia, and elevated liver enzymes. This is the first report of hemangiosarcoma in a cow with a suspected primary location of the liver and/or spleen.  相似文献   
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During the past decade the British livestock industry has suffered from several major pathogen outbreaks, and a variety of regulatory and disease control measures have been applied to the movement of livestock with the express aim of mitigating the spread of infection. The Rapid Analysis and Detection of Animal-related Risks (RADAR) project, which has been collecting data on the movement of cattle since 1998, provides a relatively comprehensive record of how these policies have influenced the movement of cattle between animal holdings, markets, and slaughterhouses in Britain. Many previous studies have focused on the properties of the network that can be derived from these movements--treating farms as nodes and movements as directed (and potentially weighted) edges in the network. However, of far greater importance is how these policy changes have influenced the potential spread of infectious diseases. Here we use a stochastic fully individual-based model of cattle in Britain to assess how the epidemic potential has varied from 2000 to 2009 as the pattern of movements has changed in response to legislation and market forces. Our simulations show that the majority of policy changes lead to significant decreases in the epidemic potential (measured in multiple ways), but that this potential then increases through time as cattle farmers modify their behaviour in response. Our results suggest that the cattle industry is likely to experience boom-bust dynamics, with the actions that farmers take during epidemic-free periods to maximise their profitability likely to increase the potential for large-scale epidemics to occur.  相似文献   
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The objective of this study was to describe the kinetics of urinary recovery and to evaluate the effects of postmucosal factors on urinary recovery of 5 intravenously administered saccharides. Ten cats received an isotonic sugar solution containing lactulose, rhamnose, xylose, methylglucose, and sucrose intravenously. These sugars were selected because of their prior use for intestinal permeability and mucosal function testing in humans and dogs. Urethral catheterization with a closed collection system was used for collection of cumulative urine samples prior to and 2, 4, 6, 8, 10, 12, and 24 h after administration of the sugar solution. High-pressure anion exchange liquid chromatography with pulsed amperometric detection was used to measure the concentrations of each sugar in the urine and calculate urinary recovery. Twenty-four hour cumulative urinary recovery for each sugar from the cats, was lower than expected compared to dogs and humans. All 5 sugars had the highest percentage of urinary recovery during the first 2 h after administration. Mean sugar elimination rate constants and half-lives ranged from 0.268/h for methylglucose to 0.415/h for lactulose and 1.67 h for lactulose to 2.59 h for methylglucose, respectively. Metabolism and incomplete urine collection are possible reasons for lower cumulative urinary recoveries of these 5 sugars in cats compared with dogs. Although these 5 sugars are not ideal marker molecules, they may still be useful for intestinal permeability and mucosal function testing in cats.  相似文献   
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It is commonplace for trainers and judges to comment that riders are “crooked” or “collapsed in the hip.” This asymmetrical posture will likely have a significant effect on stability/balance and may subsequently have a detrimental effect on performance. Although the effects of asymmetry on athlete performance has received much attention on human-only sports, there has been little scientific research investigating the influence of these factors in equestrianism, despite anecdotal acknowledgment that “a good seat” and core stability has strong influence on the horse and that crookedness may contribute to high incidences of back pain in both the rider and horse. Asymmetry among athletes has been shown to lessen after physiotherapy intervention (PI).This study examined whether the effect of PI to a group of experienced riders improved seated postural stability (determined as the root mean square [RMS] of the center of pressure signal in the medial–lateral directions) collected for more than 30 seconds and medial–lateral symmetry in force distribution when sat astride a saddle for 10 seconds. Riders were divided into 2 groups either receiving PI to the pelvic region or no intervention. After intervention, the PI group showed a significant reduction in RMS, and initial asymmetry in distribution of pressure was reduced.Preliminary findings suggest that improvements in rider asymmetry and stability can be attenuated through manipulation of the pelvic region. Further work to ascertain the benefits that targeted physiotherapy and training regimes can have on effective horse–rider communication, performance, and behavioral, anatomical, and physiological indicators of welfare in both horse and rider are justified.  相似文献   
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Conventional wisdom among rangeland professionals has been that for long-term sustainability of grazing livestock operations, rangeland should be kept in high good to low excellent range condition. Our objective was to analyze production parameters, costs, returns, and profit using data generated over a 34-yr period (1969–2002) from grazing a Clayey range site in the mixed-grass prairie of western South Dakota with variable stocking rates to maintain pastures in low–fair, good, and excellent range condition classes. Cattle weights were measured at turnout and at the end of the grazing season. Gross income · ha?1 was the product of gain · ha?1 and price. Prices were based on historical National Agricultural Statistics Services feeder cattle prices. Annual variable costs were estimated using a yearling cattle budget developed by South Dakota State University agricultural economists. All economic values were adjusted to a constant dollar using the Bureau of Labor Statistics' Consumer Price Index. Stocking rate, average daily gain, total gain, net profit, gross revenue, and annual costs · ha?1 varied among range condition classes. Net income for low–fair range condition ($27.61 · ha?1) and good range condition ($29.43 · ha?1) were not different, but both were greater than excellent range condition ($23.01 · ha?1). Over the life of the study, real profit (adjusted for inflation) steadily increased for the low–fair and good treatments, whereas it remained level for the excellent treatment. Neither drought nor wet springs impacted profit differently for the three treatments. These results support generally observed rancher behavior regarding range condition: to maintain their rangeland in lower range condition than would be recommended by rangeland professionals. Ecosystem goods and services of increasing interest to society and associated with high range condition, such as floristic diversity, hydrologic function, and some species of wildlife, come at an opportunity cost to the rancher.  相似文献   
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