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Fasciolosis is an endemic zoonotic parasitic disease with significant impacts on human health and both animal health and production. Early post-infection impacts on the host remain unclear. The objective of this study was to determine the changes, if any, to levels of endotoxin in cattle plasma in response to early-stage infection with Fasciola hepatica. Thirty-six (36) commercial bred cattle were experimentally infected with approximately 400 viable metacercariae. Plasma lipopolysaccharide (endotoxin) levels were examined on 24 occasions from 0 h before infection to 336 h after infection using the Limulus Amoebocyte Lysate chromogenic end point assay and compared with that of six (6) uninfected control animals. Peak lipopolysaccharide levels in infected animals were reached at 52 h after infection and returned to pre-infection levels at time 144 h after infection. Infected animals had significantly elevated lipopolysaccharide levels between 24 and 120 h after infection when compared to uninfected animals. The mean change in endotoxin units (EU)/mL over time after infection was statistically significant in infected animals. Elevations of lipopolysaccharide occurred in all infected animals suggesting a possible repeatable and titratable endotoxemia conducive to therapeutic agent model development.  相似文献   
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Ischemia and infarction of the spinal cord is a known cause of acute spinal injury in dogs. Currently, the diagnosis of spinal cord infarction in small animals is based on history, clinical signs, and the exclusion of other differentials with radiography and myelography. It is a diagnosis only confirmed through necropsy examination of the spinal cord. The aim of this paper is to describe the Magnetic resonance imaging (MRI) findings of the spinal cord of dogs with suspected spinal cord infarcts to utilize this technology for antemortem support of this diagnosis. This retrospective study evaluated the spinal MR examinations of 11 dogs with acute onset of asymmetric nonpainful myelopathies. All patients except one (imaged at 2 months) were imaged within 1 week of clinical signs and managed conservatively with minimal medical and no surgical intervention. They were followed clinically for a minimum of 4 months after discharge. MR findings in all dogs were characterized by focal, intramedullary, hyperintense lesions on T2-weighted images with variable contrast enhancement similar to what is reported in humans. Though it could not be used to diagnose spinal cord infarction definitively, MRI was useful in excluding extramedullary spinal lesions and supporting intramedullary infarction as a cause of the acute neurologic signs. Together with the history and clinical examination findings, MRI is supportive of a diagnosis of spinal cord infarction.  相似文献   
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Bluetongue virus serotypes 1 and 3 infection in Poll Dorset sheep   总被引:1,自引:0,他引:1  
Objective To study the clinical signs following bluetongue virus serotypes 1 and 3 infection in Poll Dorset sheep.
Design A clinical and pathological study.
Procedure Twenty Poll Dorset sheep were inoculated with bluetongue virus serotypes 1 or 3, each inoculum having a different passage history. The sheep were examined daily and their clinical appearance and rectal temperatures recorded. Heparinised and non-heparinised blood samples were taken at intervals for virological and serological study. Gross pathological findings were recorded for several sheep at necropsy and tissue samples were collected from three sheep for virological studies.
Results All inoculated sheep developed clinical disease. The clinical signs and gross pathological changes varied considerably but were consistent with damage to the vascular endothelial system. There was a decline in the titres of infectious bluetongue virus and of antigen in tissues collected between 7 and 12 days after infection.
Conclusions The severity of disease was related to the speed of onset and duration of pyrexia and not the development or titre of viraemia. Generally, those animals with sensitive mouths, depression, coronitis, recumbency and reluctance to move were the most debilitated. Whole blood was the most reliable source of infectious virus from acutely and chronically infected and convalescent animals. However, tissue samples particularly spleen, collected from dead or killed animals suffering from either peracute or acute forms of disease were most appropriate for the rapid confirmation of a clinical diagnosis.  相似文献   
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Inhibitors of cyclin‐dependent kinases, as roscovitine, have been used to prevent the spontaneous resumption of meiosis in vitro and to improve the oocyte developmental competence. In this study, the interference of oil overlay on the reversible arrest capacity of roscovitine in sheep oocytes as well as its effects on cumulus expansion was evaluated. For this, cumulus‐oocyte complexes (COCs) were cultured for 20 h in TCM 199 with 10% foetal bovine serum (Control) containing 75 μm roscovitine (Rosco). Subsequently, they were in vitro matured (IVM) for further 18 h in inhibitor‐free medium with LH and FSH. The culture was performed in Petri dishes under mineral oil (+) or in 96 well plates without oil overlay (?) at 38.5°C and 5% CO2. At 20 and 38 h, the cumulus expansion and nuclear maturation were evaluated under stereomicroscope and by Hoechst 33342 staining, respectively. No group presented cumulus expansion at 20 h. After additional culture with gonadotrophins, a significant rate of COCs from both Control groups (+/?) exhibited total expansion while in both Rosco groups (+/?) the partial expansion prevailed. Among the oocytes treated with roscovitine, 65.2% were kept at GV in the absence of oil overlay while 40.6% of them reached MII under oil cover (p < 0.05). This meiotic arrest was reversible, and proper meiosis progression also occurred in the Control groups (+/?). So, the culture system without oil overlay improved the meiotic inhibition promoted by roscovitine without affecting the cumulus expansion rate or the subsequent meiosis progression.  相似文献   
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Pulmonary edema is the most common complication of left‐sided heart failure in dogs and early detection is important for effective clinical management. In people, pulmonary edema is commonly diagnosed based on transthoracic ultrasonography and detection of B line artifacts (vertical, narrow‐based, well‐defined hyperechoic rays arising from the pleural surface). The purpose of this study was to determine whether B line artifacts could also be useful diagnostic predictors for cardiogenic pulmonary edema in dogs. Thirty‐one normal dogs and nine dogs with cardiogenic pulmonary edema were prospectively recruited. For each dog, presence or absence of cardiogenic pulmonary edema was based on physical examination, heartworm testing, thoracic radiographs, and echocardiography. A single observer performed transthoracic ultrasonography in all dogs and recorded video clips and still images for each of four quadrants in each hemithorax. Distribution, sonographic characteristics, and number of B lines per thoracic quadrant were determined and compared between groups. B lines were detected in 31% of normal dogs (mean 0.9 ± 0.3 SD per dog) and 100% of dogs with cardiogenic pulmonary edema (mean 6.2 ± 3.8 SD per dog). Artifacts were more numerous and widely distributed in dogs with congestive heart failure (P < 0.0001). In severe cases, B lines increased in number and became confluent. The locations of B line artifacts appeared consistent with locations of edema on radiographs. Findings from the current study supported the use of thoracic ultrasonography and detection of B lines as techniques for diagnosing cardiogenic pulmonary edema in dogs.  相似文献   
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BackgroundImplantable cardioverter defibrillators (ICD) are programmed to detect ventricular arrhythmias and terminate them by delivering an electrical shock. A defibrillation threshold (DFT) at least 10 J below the maximum device output is recommended for successful therapy. Shock waveform configuration is a programmable parameter used to achieve a low DFT. It is hypothesized that a fixed-pulse configuration results in lower defibrillation energy requirements than a fixed-tilt configuration.Animals10 mongrel dogs.Materials and methodsICD generator and transvenous lead were surgically implanted. Defibrillation threshold was determined using a protocol guided by the upper limit of vulnerability. Fixed-pulse and fixed-tilt (50%/50%) waveform configurations were tested in a random order. Plasma cardiac troponin I (cTnI) was measured for signs of myocardial injury.ResultsThe experiment was completed in 9 dogs. Overall mean DFT value was 424 ± 88 V (9.2 ± 3.9 J). Mean differences among voltage, energy and impedance at the DFT for fixed-pulse (422 ± 97 V, 9.1 ± 4.2 J, 62.6 ± 13.8 Ω) and fixed-tilt (426 ± 83 V, 9.3 ± 3.8 J, 62.8 ± 18.5 Ω) configurations were not statistically significant (All P > 0.21). Cardiac TnI concentration changed from 0.03 ng/mL (95% CI: 0.02–0.04) at baseline to 0.11 ng/mL (95 CI: 0.08–0.16) after DFT was obtained with the first waveform configuration and 0.19 ng/mL (95% CI: 0.13–0.28) at the end of the study period. There were no significant changes in heart rate, end-tidal CO2 and blood pressure over time (all P > 0.09).ConclusionThe tested ICD device and lead placement reliably produced acceptable DFT values, based on a 10-J safety margin below the maximum device output. A benefit of fixed-pulse configuration could not be demonstrated over the standard fixed-tilt waveform. Signs of acute myocardial damage from repeated high-voltage shocks and episodes of ventricular fibrillation seemed of limited clinical significance.  相似文献   
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