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51.
The spatial, temporal, and spatio-temporal features of the 2001 British foot-and-mouth disease epidemic in selected areas within the counties of Cumbria and Devon, which experienced the greatest incidence of disease, are described using hazard functions, extraction mapping and the space-time K-function. In Cumbria, the hazard of foot-and-mouth disease infection peaked at 2.8% in the week commencing 8 March 2001 and farm holdings in this area continued to be identified with disease to 12 September 2001. In contrast, peak infection hazard in Devon was 0.7% in the week commencing 15 March 2001 and eradication of the disease was achieved in this area by 31 May 2001. Persistence of the disease in Cumbria was consistent with: (1) many cattle holdings infected early in the epidemic (creating a high environmental viral load), and (2) a relatively large amount of medium-to-long-distance spread of the virus associated with seasonal farming activities-compounded to some extent by the movement of people and vehicles between disaggregated farm land parcels. The interaction of disease risk in Cumbria showed that premises remained infectious for longer throughout May, June and July, consistent with delays in disease detection during this period. 相似文献
52.
Fifty canine fecal samples were evaluated by five flotation procedures to compare the sensitivity of the zinc sulfate (ZnSO4) centrifugation flotation test with ZnSO4 flotation tests using benchtop incubation during the flotation period. One or more parasite species were detected in 40 samples. Results showed that centrifugation with ZnSO4 solution was significantly more likely to detect a positive sample than benchtop procedures. The difference in procedures was due primarily to increased detection of Trichuris eggs and Giardia cysts by centrifugal flotation. No significant difference was seen in the ability of benchtop procedures to detect positive samples when tests sat either for 5 or 10 minutes before examination. 相似文献
53.
Evaluation of cystatin C as an endogenous marker of glomerular filtration rate in dogs 总被引:2,自引:0,他引:2
Almy FS Christopher MM King DP Brown SA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(1):45-51
Cystatin C is a cysteine protease inhibitor produced by all nucleated cells. It is freely filtered by the glomerulus and is unaffected by nonrenal factors such as inflammation and gender. Because of greater sensitivity and specificity, cystatin C has been proposed to replace creatinine as a marker of glomerular filtration rate (GFR) in humans. The aims of this study were to validate an automated assay in canine plasma and to evaluate the usefulness of cystatin C as a marker of GFR in dogs. Western blotting was used to demonstrate cross-reactivity of an anti-human cystatin C antibody. An immunoturbidimetric assay was used to detect cystatin C in 25 clinically healthy dogs and 25 dogs with renal failure. Mean cystatin C concentration in the healthy dogs and the dogs with renal failure was 1.08 +/- 0.16 mg/L and 4.37 +/- 1.79 mg/L respectively. Intra- and interassay variability was <5%. The assay was linear (r = .974) between 0.14 and 7.53 mg/L. Both cystatin C and creatinine concentrations were measured in banked, frozen serum from 20 remnant kidney model dogs and 10 volume-depleted dogs for which GFR measurements by exogenous creatinine clearance had been determined previously. In the remnant kidney model, cystatin C was better correlated with GFR than creatinine (r = .79 versus .54) but was less well correlated with GFR in volume-depleted dogs (r = .54 versus .95). GFR measurements were repeated in the remnant kidney model dogs 60 days after initial GFR measurements. At this time, cystatin C and creatinine concentrations correlated equally well with GFR (r = .891 versus .894, respectively). Cystatin C concentration is a reasonable alternative to creatinine for screening dogs with decreased GFR due to chronic renal failure. 相似文献
54.
Polack EW King JM Cummings JF Mohammed HO Birch M Cronin T 《American journal of veterinary research》2000,61(6):609-611
OBJECTIVE: To compare concentrations of trace minerals in the spinal cord of horses with equine motor neuron disease (EMND) with those of horses without neurologic disease (control horses). ANIMALS: 24 horses with EMND and 22 control horses. PROCEDURE: Spinal cord trace mineral concentrations in horses with EMND and control horses were analyzed by use of inductively coupled plasma atomic emission spectroscopy (calcium, phosphorus, sodium, potassium, magnesium, copper, iron, manganese, nickel, zinc, aluminum, cobalt, and chromium), atomic absorption spectrophotometry (lead and cadmium), flameless atomic absorption (mercury), and fluorometry (selenium). RESULTS: Copper concentration was significantly higher in the spinal cord of horses with EMND, compared with control horses; spinal cord concentrations of all other trace minerals were similar between groups. CONCLUSION AND CLINICAL RELEVANCE: Among spinal cord trace minerals investigated in the study, only copper concentrations were significantly different between horses with EMND and horses without neurologic disease, which suggests that copper may be involved in the pathogenesis of EMND. An hypothesis of oxidative injury in this disease is supported by the finding of increased copper concentrations in the spinal cord and by low vitamin E concentrations reported by other researchers. 相似文献
55.
Pouchelon JL Martel E Champeroux P Richard S King JN 《American journal of veterinary research》2000,61(8):960-964
OBJECTIVE: To determine the effects of clomipramine hydrochloride on heart rate and rhythm in dogs. ANIMALS: 17 healthy Beagles. PROCEDURES: In experiment 1, 8 dogs received placebo or clomipramine (20 mg/kg of body weight, q 24 h, PO) for 7 days in a 2-way crossover design. In experiment 2, 9 dogs were evaluated for 48 hours before and 24 hours after oral administration of clomipramine (4 or 12 mg/kg) in a 2-way crossover design. Electrocardiogram and heart rate were monitored continuously by use of telemetry. RESULTS: A significant diurnal rhythm in heart rate was detected; minimum values were recorded at night. Administration of 20 mg of clomipramine/kg induced a significant reduction in heart rate, with peak effect achieved approximately 12 hours after dosing. Administration of 4 or 12 mg of clomipramine/kg did not result in significant changes in heart rate. Sinoatrial and second-degree atrioventricular block and ventricular escape beats were observed during periods of slow heart rate in more dogs that received clomipramine (3 to 4 of 8 dogs), compared with dogs that received placebo (1 to 2 of 8 dogs), but this difference was not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Short-term administration of clomipramine induced benign cardiovascular effects in dogs rather than the potentially dangerous arrhythmias or tachycardia reported following administration of tricyclic antidepressants to humans. Precautions regarding cardiovascular effects may not be needed for the use of clomipramine in healthy dogs. 相似文献
56.
OBJECTIVE: To determine pharmacokinetics of clomipramine and its principle metabolite (desmethylclomipramine) in the plasma of dogs after IV or oral administration of a single dose. ANIMALS: 6 male and 6 female Beagles. PROCEDURES: Clomipramine was administered IV (2 mg/kg), PO (4 mg/kg) after food was withheld for 15 hours, and PO (4 mg/kg) within 25 minutes after dogs were fed. Plasma clomipramine and desmethylclomipramine concentrations were measured by use of a gas chromatography with mass-selection method. RESULTS: Time to peak plasma concentrations of clomipramine and desmethylclomipramine following oral administration was 1.2 hours. For clomipramine, after IV administration, elimination half-life was 5 hours, mean residence time was 3 hours, and plasma clearance was 1.4 L/h/kg. Values for mean residence time and terminal half-life following oral administration were similar to values obtained following IV administration, and systemic bioavailability was approximately 20% for clomipramine and 140% for desmethylclomipramine, indicating fast absorption of clomipramine from the gastrointestinal tract and extensive first-pass metabolism. Administration of clomipramine with food did not alter the area under the concentration versus time curve for desmethylclomipramine but resulted in a 25% increase for clomipramine. Clomipramine and desmethylclomipramine were extensively bound (> 96%) to serum proteins. There were no significant differences in area under the concentration versus time curve between male and female dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that there should not be any clinically important differences in efficacy regardless of whether clomipramine is administered with or without food. 相似文献
57.
OBJECTIVE: To document pulmonary function, ventilator management, and outcome of dogs with thoracic trauma that required mechanical ventilation because of severe pulmonary contusions. DESIGN: Retrospective study. ANIMALS: 10 dogs that required mechanical ventilation because of severe pulmonary contusions caused by blunt thoracic trauma. PROCEDURE: Signalment, historical data, arterial blood gas values, oxygen tension-based indices, ventilator settings, peak inspiratory pressure, positive end-expiratory pressure, tidal volume, and minute ventilation values were retrieved from medical records. RESULTS: All 10 dogs required positive-pressure ventilation because of dyspnea following trauma and had severely abnormal pulmonary function. Survival rate to discharge was 30%. Dogs were categorized into 2 groups; group A included 5 dogs in which pulmonary function improved during ventilation, whereas group B included 5 dogs that were euthanatized because of progressive lung dysfunction (n = 4) or cardiac arrest (1). Mean +/- SD body weight of group-A dogs (30.9 +/- 15.9 kg [68 +/- 35 lb]) was significantly greater than that of group-B dogs (7.6 +/- 1.8 kg [16.7 +/- 4 lb]). Dogs with improved lung function had peak inspiratory pressure that decreased progressively, whereas lung compliance deteriorated in dogs in group B. CONCLUSIONS AND CLINICAL RELEVANCE: Dyspneic dogs with severe pulmonary contusions may require and benefit from positive-pressure ventilation Prognosis is better for dogs that weigh > 25 kg (55 lb). 相似文献
58.
King RH Campbell RG Smits RJ Morley WC Ronnfeldt K Butler K Dunshea FR 《Journal of animal science》2000,78(10):2639-2651
Sixty male and 60 female crossbred pigs were allocated to an experiment to investigate the effects of porcine somatotropin (pST) administration (0 or 6 mg/d) and dietary lysine content on growth performance, tissue deposition, and carcass characteristics over the live weight range of 80 to 120 kg. Pigs receiving pST were given diets containing 6.9, 7.8, 8.8, 9.7, 10.6, or 11.5 g lysine/kg, whereas control pigs received diets containing 4.8, 5.8, 6.9, 7.8, 8.8 or 9.7 g lysine/kg. These dietary levels ranged from 0.40 to 0.70 g available lysine/MJ of DE for pST-treated pigs and from 0.28 to 0.58 g available lysine/MJ of DE for control pigs. Pigs were individually housed in pens, and there were five replicates of each treatment. All diets contained 14.5 MJ of DE/kg and were offered for ad libitum consumption to pigs between 80 and 120 kg live weight. Growth rate increased exponentially and food conversion ratio (FCR) decreased exponentially with increasing levels of lysine. In addition, there was a significant sex x pST interaction such that pST reduced the sex difference in FCR. Growth rate was faster in boars than in gilts and was increased by pST at the higher levels of dietary lysine. Similarly, FCR was lower for boars than for gilts and was decreased by pST at the higher dietary lysine levels. The optimum growth rate and FCR were defined as the lysine level at which growth rate and FCR were 95% and 105%, respectively, of the lysine plateau. The optimum growth rate and FCR were achieved at similar dietary lysine contents and were approximately 0.35 and 0.52 g available lysine/MJ of DE for control and pST-treated pigs, respectively. Protein deposition in the carcass increased exponentially with increasing dietary lysine level, was higher in boars than in gilts, and was increased by pST at the higher dietary lysine contents. Sex had no effect on dietary lysine required to maximize protein deposition. The dietary lysine contents required to ensure 95% of plateau protein deposition of 104 and 153 g/d were 0.39 and 0.55 g available lysine/MJ of DE for control and pST-treated pigs, respectively. The increase in lysine requirement with pST seems to be commensurate with the increase in protein deposition. 相似文献
59.
Johnson EH Windsor JJ Muirhead DE King GJ Al-Busaidy R 《Veterinary research communications》2000,24(1):63-67
Veterinary Research Communications - 相似文献
60.
Buergelt CD Layton AW Ginn PE Taylor M King JM Habecker PL Mauldin E Whitlock R Rossiter C Collins MT 《Veterinary pathology》2000,37(5):428-438
Gross and histopathologic examinations were performed on 70 North American bison (Bison bison) from a Mycobacterium avium paratuberculosis culture-positive herd. The bison examined were part of a breeding herd totaling 2,800 animals. Eight of 70 (11%) animals had gross findings of intestinal mucosal thickening, and 16 of 70 (23%) of the animals had enlarged mesenteric lymph nodes. Histologic lesions compatible with Johne's disease were diagnosed in 30 of 70 (43%) bison on the basis of the demonstration of noncaseating granulomatous inflammatory infiltrates and of one or more acid-fast bacilli characteristic of Mycobacterium avium paratuberculosis. A suspicious diagnosis of Johne's disease was obtained in 11 of 70 (16%) bison on the basis of the observation of noncaseating granulomatous inflammatory infiltrates without demonstrable acid-fast bacteria. Twenty-nine of 70 (41%) animals were assessed as histologically paratuberculosis free. Histologic results were compared to Johne's disease tests such as culture, serology, and polymerase chain reaction, which were performed on some of the cohort animals. 相似文献