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131.
S J Duffy R B Morrison D G Thawley 《Journal of the American Veterinary Medical Association》1991,199(1):66-70
Knowledge of the factors that place susceptible gilts at highest risk of pseudorabies virus (PRV) infection in a quarantined herd is crucial to reduce spread of PRV within the herd. Cohorts of PRV seronegative gilts were monitored in 17 herds that were endemically infected with PRV to determine the location of breeding females at the time of infection with PRV and identify herd characteristics and management and housing factors that may influence spread of PRV in the breeding section of swine herds endemically infected with PRV. Blood samples were collected every 1 to 2 months for an average of 13.6 months. In addition, blood was collected from a representative sample of finishing pigs (greater than or equal to 20 weeks old) 3 times per year to determine their serologic PRV status. Incidence rates and relative risks of PRV infection were estimated for 4 areas of the breeding section: gestation barn, gilt pool, farrowing room, and breeding area. Overall, 28, 11, 8, and 2 females became infected with PRV in each of these areas, respectively. The greater number of females infected in the gestation barns, compared with the number of females infected in other locations, is probably a consequence of being at risk for a longer period rather than of a higher incidence rate. Herd size, common housing for gilts in the gilt pool and sows, and serologic pattern of PRV infection in finishing pigs were associated with the detection of spread of PRV in the breeding section of the 17 herds.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
132.
C A Wyse T Preston S Love D J Morrison J M Cooper P S Yam 《American journal of veterinary research》2001,62(12):1939-1944
OBJECTIVE: To assess the 13C-octanoic acid breath test for determining gastric emptying in dogs. ANIMALS: 6 healthy adult dogs. PROCEDURE: Food was withheld for 12 hours before each test. Expired air was collected 30 minutes and immediately before each test and at frequent intervals thereafter for 6 hours. Concentration of 13CO2 in expired air was determined by use of continuous-flow isotope-ratio mass spectrometry. Basal concentration of 13CO2 was measured in dogs that were not fed a test meal. Effects of the standard unlabeled test meal on basal concentration of 13CO2 were then assessed. The optimum dose of substrate was determined by measuring 13CO2 concentration after ingestion of the standard test meal containing 50 or 100 mg of 13C-octanoic acid, whereas effect of energy density of the test meal on gastric emptying was determined after ingestion of the standard or high-energy labeled test meal. Gastric emptying coefficient (GEC), time to peak 13CO2 concentration (tmax), and half-dose recovery time (t(1/2)) were calculated. RESULTS: Basal concentration of 13CO2 in expired air was not significantly affected by ingestion of the unlabeled test meal. However, 13CO2 concentration significantly increased in a dose-dependent manner after ingestion of the labeled meal. Gastric emptying coefficient, and were significantly different between dogs fed the standard and high-energy test meals, indicating that ingestion of a high-energy meal delays gastric emptying. CONCLUSIONS AND CLINICAL RELEVANCE: The 13C-octanoic acid breath test may be a useful noninvasive and nonradioactive method for assessment of gastric emptying in dogs. 相似文献
133.
134.
Chronic renal disease is an important clinical problem in dogs. Until recently, diffuse renal fibrosis with chronic renal failure has been attributed mainly to chronic interstitial nephritis, itself considered to be the end stage of acute leptospiral nephritis. A clinical and morphological analysis of eight cases of chronic glomerulonephritis is described and a comparison made with eight dogs suffering from severe chronic interstitial nephritis. Clinically and biochemically, the two diseases were virtually indistinguishable, both resulting in uraemia. A possible distinguishing feature of chronic interstitial nephritis was the anaemia which was absent from chronic glomerulonephritis cases. Morphologically, the two diseases appeared to be distinguishable on three grounds; the pattern and severity of fibrosis, the degree of fibrin deposition and the immunofluorescence findings. 相似文献
135.
Evidence for the presence of circulating virus-immune complexes in dogs experimentally infected with canine adenovirus was found when deposits of canine IgG were present in the glomeruli of recipient mice. This passive transfer of complexes occurred only with serum taken at the height of the disease when antibody titres were low and when deposition of complexes in the donor dogs was maximal. Transfer of complexes was not obtained early in the disease (no circulating antibody and minimal deposition of complexes) nor later in the disease (high circulating antibody and minimal complex deposition). 相似文献
136.
Adenovirus-mediated gene delivery of anticytokines is a powerful tool for modulating the cytokine environment under conditions of respiratory disease. In order to determine the feasibility of cytokine modulation in the context of respiratory disease in swine, nonreplicating E1- and E3-deficient adenovirus constructs expressing a model protein, beta-galactosidase, and an anticytokine, the IL-1 receptor antagonist (IL-1Ra), were evaluated for in vitro expression in porcine PK15 cells, and in vivo following endotracheal instillation into the lungs. beta-Galactosidase and IL-1Ra were readily expressed in vitro in swine cells. Endotracheal administration of lacZ-containing adenovirus demonstrated that endothelial and epithelial cells in the alveolar spaces and bronchi of the middle and lower lobes were the principal sites of infection and expression, whereas beta-galactosidase staining was not observed in the upper lobe. Endotracheal administration of IL-1Ra recombinant adenovirus resulted in sustained expression of IL-1Ra into the alveolar spaces, where it was recovered in a concentration of 660 pg/ml in 500 ml of lavage fluid, equivalent to 330 ng IL-1Ra, in the lungs 7 days after treatment. Moreover, in vivo instillation of nonreplicating adenovirus did not induce an inflammatory response in the 1-week time frame of the study period. Lung weight as a percent of body weight, serum zinc, serum amyloid A, leukocyte differentials, neutrophil activity, and TNF levels all were the same between untreated pigs and pigs treated with either recombinant adenovirus. The results indicate that the delivery of IL-1Ra to swine lungs via nonreplicating, recombinant adenovirus may be an effective method for in vivo modulation of IL-1 activity and investigation of cytokine involvement in respiratory disease pathogenesis. 相似文献
137.
Assessment of the rate of solid-phase gastric emptying in ponies by means of the 13C-octanoic acid breath test: a preliminary study 总被引:1,自引:0,他引:1
The aim of this study was to assess the feasibility of applying the 13C-octanoic acid breath test for assessment of gastric emptying in ponies by investigating the pattern of 13C enrichment in breath following the administration of a test meal +/- 13C-octanoic acid. After a 14 h fast, the ponies received either no meal (Test I) or a standardised test meal labelled with 0 mg (Test II), 125 mg (Test III), 250 mg (Test IV) or 500 mg (Test V) 13C-octanoic acid. For each test (I-V), exhaled breath samples were collected in duplicate at 1 h and immediately before ingestion of the test meal and at frequent intervals thereafter for 12 h. Breath samples were analysed by continuous flow isotope ratio mass spectrometry. Three indices of breath 13C-enrichment were computed; half dose recovery time (t1/2), gastric emptying coefficient (GEC) and time to peak breath 13C-enrichment t(max). For Tests I and II, the ratio of 13CO2:12CO2 remained stable for the duration of the sampling period. For Tests III, IV and V, an increase in the ratio of 13CO2:12CO2 was detected. The test was reproducible within individuals, and intersubject variation was low. Further validation studies of this noninvasive technique are justified. 相似文献
138.
Gionfriddo JR Melgarejo T Morrison EA Alinovi CA Asem EK Krohne SG 《American journal of veterinary research》2000,61(10):1289-1293
OBJECTIVE: To analyze and compare contents of the preocular tear films of llamas and cattle. ANIMALS: 40 llamas and 35 cattle. PROCEDURE: Tear pH was determined by use of a pH meter. Total protein concentration was determined by use of 2 microtiter methods. Tear proteins were separated by use of electrophoresis and molecular weights of bands were calculated. Western blot immunoassay was used to detect IgA, lactoferrin, transferrin, ceruloplasmin, alpha1-antitrypsin, alpha1-amylase, and alpha2-macroglobulin. Enzyme electrophoresis was used to detect proteases. RESULTS: The pH of llama and cattle tears were 8.05 +/- 0.01 and 8.10 +/- 0.01, respectively. For results of both methods, total protein concentration of llama tears was significantly greater than that of cattle tears. Molecular weights of tear protein bands were similar within and between the 2 species, although llama tears had a distinct 13.6-kd band that was not detected in cattle. Lactoferrin, IgA, transferrin, ceruloplasmin, alpha1-antitrypsin, alpha1-amylase, alpha2-macroglobulin, and proteases were detected in both species. CONCLUSIONS AND CLINICAL RELEVANCE: Llama tears have significantly greater total protein concentration than cattle tears, whereas pH is similar between species. Because little variation was detected within species for the number and molecular weight of protein bands, pooling of tears for analysis is justified. Results suggest that lactoferrin, ceruloplasmin, transferrin, alpha1-antitrypsin, alpha2-macroglobulin, alpha1-amylase, and IgA are present in the tears of llamas and cattle. 相似文献
139.
Morrison WI Bourne FJ Cox DR Donnelly CA Gettinby G McInerney JP Woodroffe R 《The Veterinary record》2000,146(9):236-242
In last week's Veterinary Record, members of the Independent Scientific Group on Cattle TB discussed the approach they are adopting in attempting to develop sustainable strategies for controlling bovine tuberculosis in cattle (VR, February 19, pp 207-210). In this second, complementary article, they consider the extent to which efforts to control the disease may be constrained by limitations in current testing procedures. 相似文献
140.
J.E. Slovak C. Wang J.A. Morrison K.L. Deitz D.N. LeVine C. Otoni R.R. King L.E. Gerber K.R. Hanson A.P. Lundberg A.E. Jergens 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(5):1442-1446