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991.
Reasons for performing study: Postural balance can be quantified using stabilographic variables derived from force plate data that describe movements of the horse's centre of pressure (COP) in the horizontal plane. Most force plates are not large enough to accommodate all 4 limbs of a standing horse, so the study was designed to assess whether representative stabilographic data could be collected from the forelimbs or hindlimbs. Objective: To determine whether stabilographic data from either the forelimbs or the hindlimbs were representative of data for the total body. Methods: Stabilographic data (960 Hz) were collected from 17 sound horses standing with the forelimbs and the hindlimbs on separate force plates. To increase variability in the data, horses were of different sizes, the recording duration was varied (15–60 s) and data were collected under sighted and blindfolded conditions. Results: Correlation matrices indicated that total body stabilographic variables were highly significantly correlated with both forelimb and hindlimb data but correlation coefficients were higher for forelimb data. Forward stepwise regression selected forelimb data for inclusion in the model for 15/16 variables, the exception being mean absolute mediolateral velocity. Conclusions: Ground reaction force data from a pair of limbs, preferably the forelimbs, can be used to measure variables that represent total body postural balance in sound standing horses. Potential relevance: Stabilographic data from either the forelimbs or hindlimbs may be useful for detecting and quantifying deficiencies in postural balance in ataxic horses.  相似文献   
992.
Stallions (n = 8) were implanted with a thermal sensory device in the muscle of the neck and the subcutaneous tissue of the scrotum and then assigned to either a nonexercise (Non-EX; n = 4) or exercise (EX; n = 4) group. A motorized equine exerciser was used to work EX stallions 30 min/d for 4 d/wk during a 12-wk period from July through October 2010. Temperatures (subcutaneous scrotal, intramuscular neck, and rectal) were recorded at 0, 22, and 30 min after the start of exercise, as well as 60 and 120 min post-exercise. Hourly ambient temperature and relative humidity data were also obtained. Semen was collected at 0, 4, 8, and 12 wk and analyzed for volume, sperm concentration, total sperm numbers, percentages of total and progressively motile sperm, sperm morphologic characteristics, and sperm DNA quality. No effect (P > 0.05) of exercise was observed on any of the measured semen variables. Implantation of thermal sensory devices had no demonstrable acute or chronic effects on the scrotal or neck tissue, indicating that the thermal sensory devices are a safe and effective way to measure subcutaneous scrotal and neck temperatures. At 22 and 30 min of exercise, rectal and neck temperatures increased (P < 0.0001) approximately 1.9 and 2.4°C, respectively, and scrotal temperatures simultaneously increased, although not significantly (P = 0.33), approximately 0.8°C. Correlations existed between scrotal, neck, rectal, and ambient temperatures, with the correlation between scrotal and rectal temperatures being greatest (r(s) = 0.76; P < 0.0001). Although moderate exercise for a short duration in extreme heat and humidity did significantly increase core body temperatures in stallions, scrotal temperatures did not significantly increase, and sperm parameters were unaffected.  相似文献   
993.
The glycolipid CarLA (carbohydrate larval antigen) is present on the epicuticle of the infective-stage larvae of gastrointestinal nematode parasites infecting livestock. The molecule is lost from the surface of the larvae in the few days post-ingestion by a host animal, and the resulting anti-CarLA antibody response has been demonstrated to be protective in vivo. Both the anti-CarLA response, and anti-parasite immunity in general, are slow to develop, and several months of natural exposure to ingested larvae is required. The current study was designed to provide information on how the anti-CarLA response develops, and focuses on the initial recognition of the molecule by human monocyte derived dendritic cells (mdDC) in vitro. Immunofluorescence and flow cytometry demonstrated that mdDC recognise and internalise both the purified and the native form of CarLA, in the case of the latter once it is shed from the larval surface. However, the recognition of CarLA did not result in classical maturation of DC, while there was only transient or minor up-regulation of CD86, CD83, HLA-DR and CD40. Exposure of mdDC to purified CarLA resulted in the increased production of the pro-inflammatory cytokines IL-6 and to a lesser extent of IL-8 and TNF-α, and a reduced production of the anti-inflammatory cytokine IL-1RA. CarLA therefore has little ability to mature and functionally alter monocyte derived dendritic cell function.  相似文献   
994.
Fenoldopam is a selective dopamine-1 receptor agonist that causes peripheral arterial vasodilation, increased renal blood flow, and diuresis. Enthusiasm exists for the use of fenoldopam in nonpolyuric kidney injury in dogs, although pharmacokinetic data are lacking. The purpose of this study was to collect basic pharmacokinetic and hemodynamic effect data for fenoldopam when administered to healthy awake dogs. Six healthy, awake beagles were given a 180-min fenoldopam constant rate infusion at 0.8 μg/kg per minute followed by a 120-min washout period. Citrated blood was collected during and after infusion for the measurement of plasma fenoldopam concentration by HPLC with mass spectrometry. Heart rate and indirect systolic blood pressure were concurrently measured. Mean ± SD, steady-state plasma fenoldopam concentrations of 20 ± 17 ng/mL were achieved within 10 min of starting the infusion. Area under the plasma concentration-time curve was 3678 ± 3030 ng/mL · min, and plasma clearance was 66 ± 43 mL/min per kg. Elimination was rapidly achieved in all dogs. Heart rate and systolic blood pressure were unaffected by the fenoldopam infusion. Based on the results of this study, further evaluation of the effects of fenoldopam in dogs at differing doses and in dogs with clinical conditions such as acute nonpolyuric kidney injury is warranted.  相似文献   
995.
996.
Canine separation anxiety is a common behavioral problem presented to veterinarians. Associated behaviors are distressing to both dog and owner, have the potential to disrupt the human-companion animal bond, and may lead to euthanasia. The results of this study demonstrate the clinical efficacy and safety of Reconcile (fluoxetine, 1 to 2 mg/kg/day [0.45 to 0.91 mg/lb/day]), in conjunction with behavior management, for the treatment of canine separation anxiety. The beef flavored chewable formulation was palatable to treated dogs and easy to administer. This study provides to veterinarians and owners valuable information about an effective separation anxiety treatment plan that combines use of Reconcile with behavior modification.  相似文献   
997.
An 11-year-old, female, spayed cocker spaniel was presented with dysphonia caused by a solitary laryngeal mass. Excisional biopsy was performed, and a diagnosis of plasmacytoma was made on the basis of histological examination. Further investigations showed no signs of systemic involvement. Coarse fractionated radiation therapy failed to control the tumour. Therapy was successfully instituted with a conventional combination chemotherapy protocol over a period of 14 months. The dog remains disease free 30 months after diagnosis. Most solitary, extramedullary plasmacytomas in dogs arise in the gastrointestinal tract, with fewer reports in other sites. The larynx is an uncommon sight of involvement in any species, and to the authors' knowledge, this is the first report of this tumour type in the canine larynx. In contrast to the therapeutic benefits reported in humans, the combination of surgery and radiation therapy was unsuccessful in this case, although sustained remission was gained following chemotherapy.  相似文献   
998.
Scrapie is the longest known and most widely spread of the transmissible spongiform encephalopathies and remains the model for much of the research regarding these diseases. Because scrapie is a reportable disease and the subject of an active eradication program in the United States, veterinary practitioners should have a basic understanding of the disease.  相似文献   
999.
1000.
Canine adenovirus type 1 infection of a Eurasian river otter (Lutra lutra)   总被引:1,自引:0,他引:1  
A 10-year-old female Eurasian river otter (Lutra lutra) died after prolonged anorexia and weight loss in the Seoul Grand Park Zoo, Seoul, Republic of Korea. On necropsy, the liver was found to be swollen and friable with 1 lobe enlarged and necrotic. The other organs showed no significant alterations except for mild atrophy of the right kidney. Microscopically, there was multifocal hepatic necrosis. The hepatocytes around the necrotic areas were swollen and contained large basophilic intranuclear inclusions. Periportal infiltration by plasma cells and lymphocytes was also evident. Transmission electron microscopy revealed characteristic hexagonal virus particles sized approximately 70 nm in diameter in the nuclei of the hepatocytes, which were consistent with an adenovirus. Polymerase chain reaction of the formalin-fixed, paraffin-embedded liver sections was used to determine whether the virus was either the canine adenovirus type 1 (CAV-1), canine adenovirus type 2 (CAV-2), or some other viral agent. The results of these tests showed that the virus was CAV-1. To our knowledge, this is the first report on a CAV-1 infection in an otter.  相似文献   
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