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991.
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993.
A 20-year-old Warmblood gelding presented for evaluation and treatment of ventral oedema and azotaemia of unknown aetiology. On presentation, a diastolic heart murmur was appreciated and echocardiography revealed moderate aortic insufficiency due to chronic degenerative valve disease. The horse was hospitalised and failed to respond to oral and i.v. fluids and diuretics. Following discontinuation of all fluid and diuretic therapy, the horse became acutely agitated and developed monomorphic ventricular tachycardia. The ventricular tachycardia spontaneously converted to normal sinus rhythm, however the heart murmur changed in timing to a right basilar continuous murmur and bounding jugular pulses were noted. Repeat echocardiogram revealed an aorto-cardiac fistula with dissection into the basilar interventricular septum and left-sided chamber volume overload that was not previously present. Attempts at stabilisation were unsuccessful and euthanasia was elected. Post-mortem examination confirmed chronic renal disease of unknown aetiology in addition to an aorto-cardiac fistula originating from the right sinus of Valsalva with subsequent dissection into the basilar interventricular septum.  相似文献   
994.
995.
Selenium is a trace element of importance for animal health. It is essential for adequate functioning of many enzymes such as, the antioxidant enzyme, glutathione peroxidase, which protects the cell against free radicals. A muscular effort induces a rise in reactive oxygen species production which, in turn, can generate an oxidative stress. Two groups of eight racing pigeons were fed respectively with a diet containing 30.3 (control group) and 195.3 (selenium group) μg selenium/kg diet. The pigeons were submitted to a standardised simulation of a flying effort during 2 h. Blood was taken before and after the effort to measure antioxidant markers and blood parameters related to muscle metabolism. Plasma selenium concentration and glutathione peroxidase activity were significantly higher in the selenium group. There were no significant differences for the other measured parameters. As a consequence of the effort, the pigeons of the selenium group showed a higher increase of glutathione peroxidase activity and a smaller increase of plasma lactate concentration. Variations because of the effort in the other markers were not significantly different between the two groups. It is concluded that the selenium status was improved with the feeding of feedstuffs high in Selenium.  相似文献   
996.
A single screw technique is described as a temporary transphyseal bridge for the treatment of fetlock varus angular limb deformity in foals. This has been compared to tension band wiring with regards to rate of correction, cosmetic result and incidence of complications. The single screw was found to be an effective technique resulting in more rapid improvement of deviations in foals aged up to 5 months. Complications were minimal following both techniques and the final cosmetic result was better following single screw surgery.  相似文献   
997.
998.
Objectives were to investigate effects of nutritional plane and Se supply during gestation on visceral organ mass and intestinal growth and vascularization in ewes at parturition and during early lactation. Primiparous Rambouillet ewes (n = 84) were allocated to 2 × 3 × 2 factorial arrangement of treatments. Factors included dietary Se [adequate Se (ASe, 11.5 μg/kg BW) or high Se (HSe, 77.0 μg/kg BW)], nutritional plane [60% (restricted; RES), 100% (control; CON), or 140% (high; HIH)], and physiological stage at necropsy (parturition or d 20 of lactation). At parturition, lambs were removed and 42 ewes (7 per treatment) were necropsied. Remaining ewes were transitioned to a common diet which met lactation requirements and mechanically milked for 20 d. In the absence of interactions (P > 0.10), main effects are reported. At parturition, stomach complex and liver masses were greatest for HIH, intermediate for CON, and least for RES (P < 0.02). Small intestinal mass was greater (P ≤ 0.002) for HIH than RES and CON, and greater (P < 0.01) for ASe than HSe. During early lactation, RES and CON gastrointestinal masses increased disproportionally to BW (P < 0.05). At parturition, jejunal mucosal density was less (P ≤ 0.01) for RES than CON and HIH, whereas CON had greater (P < 0.003) jejunal mucosal RNA concentration and RNA:DNA than RES and HIH. Although there were no differences (P > 0.17) at parturition, jejunal cell percent proliferation was greatest in RES, intermediate in CON, and least in HIH (P ≤ 0.09) at d 20 lactation. At both stages, RES had less (P = 0.01) jejunal capillary area density than HIH and less (P ≤ 0.03) capillary surface density than CON and HIH. During lactation, jejunal capillary size was greater (P = 0.04) for ewes previously fed HSe compared with ASe. At parturition, ASe-HIH had greater (P < 0.02) jejunal mucosal endothelial nitric oxide synthase 3 mRNA than all other treatments and greater (P = 0.10) vascular endothelial growth factor (VEGF) than all treatments, except ASe-RES. In addition, CON had less (P ≤ 0.08) jejunal VEGF receptor-1 (FLT1) mRNA compared with RES and HIH, and ASe had greater (P = 0.003) FLT1 than HSe at parturition. Ewes fed HIH had greater (P = 0.04) jejunal VEGF receptor-2 mRNA compared with RES. Results indicate that maternal intestinal growth and vascularization are responsive to nutritional plane and dietary Se during gestation and undergo changes postpartum when under similar lactational management.  相似文献   
999.
Reasons for performing study: Accurate measurement of plasma fibrinogen concentrations is an important tool for assessment of horses with inflammatory diseases. Objectives: To determine the precision and accuracy of a benchtop instrument using both fresh and frozen equine plasma by comparing the plasma fibrinogen concentration measured by a benchtop instrument to 2 separate laboratory standard methods (ACL 100 and STA Compact) for fibrinogen measurement. Methods: Accuracy and precision of the VSPro was evaluated using both human fibrinogen standards and samples from horses. Fifty frozen samples from horses with gastrointestinal disease had the fibrinogen concentration measured using the ACL 1000 and the VSPro. Fifty fresh samples were collected from hospitalised horses and fibrinogen concentration was measured using the STA Compact coagulation machine and the VSPro. Correlations for measurements were performed, as well as Bland‐Altman analysis. Results: Coefficients of variability for the VSPro ranged from 7% to 15%. The VSPro fibrinogen values were well correlated to both the ACL 1000 (r = 0.94, P<0.001) and the STA Compact measurements (r = 0.926, P<0.001). Bland‐Altman analysis showed a mean bias of ‐0.83 g/l (95% confidence interval ‐2.03–0.324 g/l) for the ACL 1000 and a mean bias of ‐0.024 g/l (95% confidence interval ‐1.434–1.386 g/l) for the STA Compact. Conclusions: The VSPro appears to have adequate accuracy and precision for clinical measurement of plasma fibrinogen concentrations. Potential relevance: The VSPro provides a measurement of equine plasma fibrinogen concentration using a benchtop instrument with a rapid test time that has comparable accuracy to the fibrinogen concentration obtained from reference laboratories.  相似文献   
1000.
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