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61.
A three-year-old weimaraner was presented with lethargy, anorexia, neck pain and a soft fluctuant swelling in the thoracic inlet. A cough had been noted previously. Clinical examination revealed tachycardia, tachypnoea, pallor and a large subcutaneous swelling, with bruising, suggestive of a haematoma in the thoracic inlet. Thoracic radiographs revealed a cranial mediastinal mass which had the ultrasonographic appearance of fluid, and there was also a marked generalised interstitial lung pattern. Routine haematology revealed severe anaemia and thrombocytopenia, although coagulation tests were within normal limits. A diagnosis of immune-mediated thrombocytopenia was however made on the basis of a positive antiplatelet antibody test and a rapid response to prednisolone therapy. Furthermore, a tentative diagnosis of Angiostrongylus vasorum infection was suggested on the basis of clinical and radiographic findings, although no lungworm larvae were identified on faecal analysis. Despite initiating treatment with fenbendazole, the dog died suddenly. Postmortem examination revealed myocarditis, thrombosing arteritis, pneumonia and chronic membranoproliferative glomerulonephritis associated with A vasorum infection.  相似文献   
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This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows. The factors examined were: semen providing breed (Holstein-Friesian vs Limousin), outcome of gestation (male vs female newborn, and singleton vs twin pregnancies), lactation number, milk production at pregnancy diagnosis, plasma progesterone concentration, season of gestation (warm period, March–November vs cool period, December–February), and day of gestation (40, 90, 120, 150, 180 and 210). Pregnancy was diagnosed by transrectal ultrasound on day 40 post-insemination and by palpation per rectum on days 90, 120, 150, 180 and 210. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The relative contributions of the different factors on PAG-1 concentrations were evaluated by GLM repeated measures analysis of variance. No significant effects of the herd, foetal sex, milk production, lactation number and plasma progesterone concentrations were observed. In contrast, twin pregnancy, the use of Limousin semen and conception during the cool period were correlated with significantly increased plasma PAG-1 concentrations throughout gestation. Our data indicate that both cow well-being during early placental development, determined in our conditions by reduced heat stress when conception occurred in the cool season, and crossbreed pregnancies lead to improved PAG-1 production throughout the gestation period.  相似文献   
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High in vitro oxygen (O2) tensions are associated with enhanced levels of reactive oxygen species and cumulus oocyte complex (COC) apoptosis. The objective of this study was to determine the influence of O2 tension on cumulus cell (CC) viability from canine oocytes. Cumulus oocyte complexes were distributed into three groups (CG, T20 and T5) and two O2 tension levels (20% and 5%). The control group (CG) was matured in vitro in a humidified atmosphere with 5% CO2 in air in TCM199 with 26.19 m m sodium bicarbonate, 10% (v/v) foetal calf serum (FCS), 0.10 m m gentamicin, 0.20 m m pyruvic acid, 20 μg/ml oestradiol, 0.5 μg/ml follicle-stimulating hormone, 0.03 IU/ml human chorionic gonadotropin, and 1.0 μg/ml human somatotropin. Groups T20 and T5 were matured under 20% or 5% O2 tensions respectively in a high-glucose medium, without FCS. T20 and T5 were as CG, and supplemented with 0.1% Polyvinyl Alcohol, and 5.5 m m glucose. After 48 h of IVM, CCs from COCs were stained with propidium iodide (1.50 m m ). The results showed that viability of CCs (cytoplasmic features and nuclear morphological integrity) was different for the three groups. Rates of apoptosis were at 57.9% (521/900) for CG, 54.4% (490/900) for T20 and 38.9% (350/900) for T5 (p < 0.001). Predominant features in apoptotic cells (n = 1361) were DNA nuclear fragments (94.0%). It was concluded that CCs of canine COCs cultured in high-glucose medium showed significantly less apoptosis than those cultured in medium with FCS. Low O2 tension was efficient in reducing apoptosis in canine CCs.  相似文献   
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The global dairy industry, the predominant pathogens causing mastitis, our understanding of mastitis pathogens and the host response to intramammary infection are changing rapidly. This paper aims to discuss changes in each of these aspects. Globalisation, energy demands, human population growth and climate change all affect the dairy industry. In many western countries, control programs for contagious mastitis have been in place for decades, resulting in a decrease in occurrence of Streptococcus agalactiae and Staphylococcus aureus mastitis and an increase in the relative impact of Streptococcus uberis and Escherichia coli mastitis. In some countries, Klebsiella spp. or Streptococcus dysgalactiae are appearing as important causes of mastitis. Differences between countries in legislation, veterinary and laboratory services and farmers' management practices affect the distribution and impact of mastitis pathogens. For pathogens that have traditionally been categorised as contagious, strain adaptation to human and bovine hosts has been recognised. For pathogens that are often categorised as environmental, strains causing transient and chronic infections are distinguished. The genetic basis underlying host adaptation and mechanisms of infection is being unravelled. Genomic information on pathogens and their hosts and improved knowledge of the host's innate and acquired immune responses to intramammary infections provide opportunities to expand our understanding of bovine mastitis. These developments will undoubtedly contribute to novel approaches to mastitis diagnostics and control.  相似文献   
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Objective To compare the incidence of anesthetic complications in diabetic and nondiabetic dogs undergoing general anesthesia and phacoemulsification cataract surgery. Procedure The medical and anesthetic records of all dogs undergoing phacoemulsification cataract surgery at Davies Veterinary Specialists between 2005 and 2008 were reviewed. Anesthetic records were evaluated by an ECVAA Diplomate. Dogs for which records were incomplete were excluded. The anesthetic technique, including all drugs administered in the perioperative period, was recorded. The anesthetic complications investigated included hypotension (MAP (mmHg): ≥55 none/mild; ≤54 moderate/severe), bradycardia (<60 bpm associated with hypotension) and hypothermia (esophageal temperature <36.7 °C). Where hypotension was present, the method of and response to treatment was recorded. The incidence of severe hyperglycemia (blood glucose >13.75 mmol/L (250 mg/dL)) in the diabetic group was also assessed. Results 66 diabetic and 64 nondiabetic dogs were included in the study. Diabetic dogs were more likely to develop moderate and severe intraoperative hypotension than nondiabetic dogs. Forty‐four percent of diabetic dogs had at least one episode of severe hyperglycemia whilst anesthetized. Conclusions Diabetic dogs undergoing phacoemulsification are more likely to suffer the anesthetic complications of moderate and severe hypotension than nondiabetic dogs. The increased incidence and severity of hypotension in diabetic dogs may be explained by hypovolemia secondary to hyperglycemia and resultant osmotic diuresis.  相似文献   
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Oxidative stress represents a challenge during sperm manipulation. We have tested the effect of increasing hydrogen peroxide (H2O2) levels on red deer spermatozoa after cryopreservation, and the role of male‐to‐male variation in that response. In a first experiment, eight thawed samples were submitted to 0, 25, 50, 100 and 200 μm H2O2 for 2 h at 37°C. Intracellular reactive oxygen species (H2DCFDA‐CM) increased with H2O2 concentration, but we only detected a decrease in sperm function (motility by CASA and chromatin damage by sperm chromatin structure assay) with 200 μm . Lipoperoxidation assessed by the thiobarbituric acid reactive substance (TBARS) method increased slightly with 50 μm H2O2 and above. In a second experiment, samples from seven males were submitted to 0 and 200 μm H2O2 for 2 h, triplicating the experiment within each male. Males differed at thawing and regarding their response to incubation and H2O2 presence. We found that the kinematic parameters reflected male‐to‐male variability, whereas the response of the different males was similar for lipid peroxidation and viability. A multiparametric analysis showed that males grouped differently if samples were assessed after thawing, after incubation without H2O2 or after incubation with H2O2. Red deer spermatozoa are relatively resilient to H2O2 after thawing, but it seems to be a great male‐to‐male variability regarding the response to oxidative stress. The acknowledgement of this individual variability might improve the development of optimized sperm work protocols.  相似文献   
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