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81.
An indirect immunofluorescence (IFA) test with a 96-well, flat-bottomed microplate was developed to detect avian pneumovirus (APV) antigen in Vero cell cultures. Samples of nasal turbinates and swabs from infraorbital sinuses and trachea were collected from 4-week-old poults experimentally inoculated with APV. The APV titers by tissue culture IFA staining were compared with that of visual reading of cytopathic effect (CPE). The ability of IFA staining to detect APV antigen correlated well with visualizing CPE. The use of IFA staining of Vero cell cultures allowed detection of APV in substantially less time than the use of visualizing CPE. In addition, the use of IFA allowed specific identification of the virus in cell culture.  相似文献   
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83.
This fecal prevalence study targeted cattle from 7 large (10 000 to > 40 000 head) commercial feedlots in Alberta as a means of establishing Campylobacter levels in cattle just prior to animals entering the food chain. Overall, 87% [95% confidence interval (CI) = 86–88] of 2776 fresh pen-floor fecal samples were culture positive for Campylobacter species, with prevalences ranging from 76% to 95% among the 7 feedlots. Campylobacter spp. prevalence was 88% (95% CI = 86–90) in the summer (n = 1376) and 86% (95% CI = 85–88) in the winter (n = 1400). In addition, 69% (95% CI = 66–71) of 1486 Campylobacter spp. positive samples were identified as Campylobacter jejuni using hippurate hydrolysis testing. Of those, 64% (95% CI = 58–70) of 277 and 70% (95% CI = 67–72) of 1209 Campylobacter isolates were identified as C. jejuni in winter and summer, respectively. After accounting for clustering within pen and feedlot, feedlot size and the number of days on feed were associated with Campylobacter spp. isolation rates. The high isolation rates of Campylobacter spp. and C. jejuni in feedlot cattle feces in this study suggest a potential role for feedlot cattle in the complex epidemiology of campylobacters in Alberta.  相似文献   
84.
Reasons for performing study: There is limited objective information available on the treatment and the long‐term response to treatment of the different types of equine sinus disease. Objectives: To document the treatments and long‐term response to these treatments in 200 cases of equine sinus disease (1997–2009). Methods: The treatments of horses affected with subacute primary sinusitis (n = 52); chronic primary sinusitis (n = 37); dental sinusitis (n = 40); sinus cyst (n = 26); traumatic (n = 13); dental‐related oromaxillary fistula (n = 8); sinus neoplasia (n = 10); mycotic sinus disease (n = 7); and intrasinus progressive ethmoid haematoma (n = 7) and the long‐term response to these treatments were retrospectively reviewed. Results: Treatments evolved throughout the study and latterly were as conservative as possible, including sinoscopic lavage and standing sinusotomy, with a maxillary sinusotomy approach preferred for the mainly mature horses treated in this study. Removal of intrasinus inspissated pus, including transendoscopically (by sinusotomy and via existing sinonasal fistulae), was the main treatment for chronic primary sinusitis and sinonasal fistulation was seldom performed latterly. Attempted oral extraction of infected cheek teeth, even if unsuccessful, facilitated subsequent dental repulsion, resulting in few post operative problems. Sinus cyst removal carried an excellent prognosis. Except for cases of sinus neoplasia (only 22% cured), an excellent long‐term response to treatment (91% fully cured, 7% partially cured) was obtained for all other types of sinus disease following a median of one treatment. Conclusions: More conservative treatments, including removal of intrasinus inspissated pus by sinoscopy, pre‐existing sinonasal fistula or sinusotomy, are effective for chronic primary sinus disease. Standing sinusotomy, mainly using a small maxillary site, was suitable for most cases of sinus disease in mature horses.  相似文献   
85.
The aims of this study were to objectively evaluate and quantify the process of post-extraction cheek teeth (CT) dental drift in horses, and to report on associated disorders of CT wear and long-term periodontal health. Fifty horses that had CT oral extraction because of apical infection were prospectively re-examined and a full oral examination, including measurements of some dental parameters, was performed.Narrowing of the extraction space was noted in all cases with complete closure occurring in 18% of horses. The rate of dental drift was calculated as 15.7% of extraction space/year (range 4–50%) and was not associated with the age at extraction (P = 0.78) or frequency of dental care since extraction (P = 0.48). There was a significant negative relationship between the rate of dental drift and the duration of time since extraction (P = 0.008). Overgrowths were present on the opposite CT row in 98% of horses, including opposite the extracted CT and on the Triadan 06s and 11s. No significant difference was noted in either the number of diastemata (P = 0.9) or periodontal disease score (P = 0.8) between the extraction and the contralateral cheek tooth rows.  相似文献   
86.
87.
The present peer‐reviewed veterinary literature contains conflicting information regarding the impact of surgical margin completeness on risk of local tumour recurrence in canine soft tissue sarcoma (STS). This systematic review and meta‐analysis was designed to answer the clinical question: “Does obtaining microscopically tumour‐free surgical margins reduce risk for local tumour recurrence in canine cutaneous and subcutaneous STS?” A total of 486 citations were screened, 66 of which underwent full‐text evaluation, with 10 studies representing 278 STS excisions ultimately included. Cumulatively, 16/164 (9.8%) of completely excised and 38/114 (33.3%) of incompletely excised STS recurred. Overall relative risk of 0.396 (95% confidence interval = 0.248‐0.632) was calculated for local recurrence in STS excised with complete margins as compared to STS excised with incomplete margins. Risk of bias was judged to be low for all studies in terms of selection bias and detection bias but high for all studies in terms of performance bias and exclusion bias. The results of the present meta‐analysis, coupled with the results of individual previous studies, strongly suggest that microscopically complete surgical margins confer a significantly reduced risk for local tumour recurrence in canine STS. Future studies ideally should adhere to standardized conducting and reporting guidelines to reduce systematic bias.  相似文献   
88.
Background: The diagnosis of canine pancreatitis is challenging. Clinical presentation often includes nonspecific clinical signs, such as vomiting, anorexia, and abdominal discomfort. Increased serum lipase activity can be indicative of pancreatitis; however, it can also be increased with other conditions. An immunoassay for measurement of canine pancreas‐specific lipase in canine serum that would be suitable for commercial application and provide rapid results would be beneficial. Objective: The goal of this study was to validate the Spec cPL assay, a commercially available ELISA for the quantitative measurement of canine pancreas‐specific lipase. Methods: Dynamic range, dilutional linearity, precision, interfering substances, assay stability, and reproducibility were investigated for analytical validation. The method was compared with the reference assay, canine pancreatic lipase immunoreactivity (cPLI), and included evaluation of a sample population of dogs and bias. Results: Analytical validation showed a dynamic range of 36–954 μg/L; good precision (intra‐ and interassay coefficient of variation <12%); absence of interference from lipid, hemoglobin, or bilirubin; 12‐month kit stability; and good reproducibility. Method comparison showed a positive bias relative to the cPLI reference method; however, the bias can be accommodated by adjustment of decision limits. The upper limit of the reference interval for Spec cPL was determined to be 216 μg/L based on the upper 97.5th percentile of results from 93 clinically healthy, kennel‐housed dogs. Conclusions: Validation data demonstrated that the Spec cPL assay provides reproducible results for canine pancreas‐specific lipase. A readily available assay for measurement of this enzyme allows broader clinical utilization of this analytical tool, generating timely results to aid in the diagnosis of canine pancreatitis.  相似文献   
89.
An irregular cardiac rhythm was identified in ten adult cows during auscultation of the heart and was subsequently characterized as atrial fibrillation by electrocardiography. The occurrence of the arrhythmia was associated with primary, organic disease of the heart in two animals which had valvular endocarditis. In seven of the other cows secondary or “functional” atrial fibrillation occurred in association with disorders of abdominal origin, six gastrointestinal disorders and one uterine torsion. Spontaneous conversion to normal sinus rhythm occurred in six cows after elimination of the primary disease.  相似文献   
90.
Disease resulting from infection by Zygomycetes fungi (including two groups of coenocytic fungal pathogens: the Mucormycota and the Entomophthoramycota) has been collectively referred to as zygomycosis. Clinical disease associated with both the Mucormycota and the Entomophthoramycota is rarely encountered in horses. Potentially life-threatening, mucormycosis is an angioinvasive disease that principally affects immunocompromised individuals. The order of Entomophthorales include two genera: Conidiobolus and Basidiobolus. The most common of these, Conidiobolus coronatus, typically causes chronic necrohaemorrhagic tumefactions in the nostrils, nasal passages and nasopharyngeal walls of immunocompetent equine hosts, most commonly seen in the south-eastern USA and parts of Australia. Infection by Basidiobolus ranarum is reported less frequently and usually causes solitary ulcerative skin lesions with pruritus. This short commentary intends to complement the accompanying review of conidiobolomycosis by summarising reported cases of mucormycosis and basidiobolomycosis in horses. Moreover, some new information regarding taxonomic challenges to traditional ‘Zygomycosis’ classification is presented.  相似文献   
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