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51.
Johnson AL Probst CW DeCamp CE Rosenstein DS Hauptman JG Kern TL 《American journal of veterinary research》2002,63(1):42-46
OBJECTIVE: To define the vertical position of the patella in clinically normal large-breed dogs. SAMPLE POPULATION: Cadavers of 13 clinically normal large-breed dog. PROCEDURE: Both hind limbs were harvested with intact stifle joints and mounted on a positioning device that allowed full range of motion of the stifle joint. Lateral radiographic views were obtained with the stifle joints positioned at each of 5 angles (148 degrees, 130 degrees, 113 degrees, 96 degrees, and 75 degrees). Vertical position of the patella through a range of motion was depicted on a graph of mean stifle angle versus corresponding mean proximal patellar position (PPP) and distal patellar position (DPP) relative to the femoral trochlea for each dog. Ratio of length of the patellar ligament to length of the patella (L:P) was determined for each dog. Overall mean, SD, and 95% confidence intervals for L:P were calculated for all dogs. RESULTS: Evaluation of vertical position of the patella through a range of motion revealed a nearly linear relationship between joint angle and PPP and joint angle and DPPF Evaluation of L:P results did not reveal significant differences between limbs (left or right) or among joint angles. Overall mean +/- SD L:P for all dogs was 1.68 +/- 0.18 (95% confidence interval, 1.33 to 2.03). CONCLUSIONS AND CLINICAL RELEVANCE: The L:P proved to be a repeatable measurement of vertical patellar position, which is independent of stifle angles from 75 degrees to 148 degrees.This measurement could be used as a quantitative method for diagnosing patella alta and patella baja in large-breed dogs. 相似文献
52.
In the US eradication program for bovine tuberculosis, a definitive diagnosis depends on the isolation of Mycobacterium bovis. However, in some cases bacterial culture is unsuccessful, even though the tissue is considered suspicious by histopathology because granulomatous lesions and acid-fast organisms are present. The purpose of this study was to determine if polymerase chain reaction (PCR) tests on formalin-fixed tissue would successfully identify the organisms observed in suspect lesions from culture-negative animals. Diagnostic laboratory records were used to select paraffin blocks of tissue from 102 ruminants that had suspect microscopic lesions but no bacterial isolation. Sections from these blocks were examined with PCR primers for IS6110 to detect Mycobacterium tuberculosis complex infection, or with 16S ribosomal RNA and IS900 primers for detection of Mycobacterium avium. The PCR tests successfully identified a mycobacterial infection in 58 of 102 tissues, including 41 M. tuberculosis complex and 17 M. avium (11 subspecies paratuberculosis). These results demonstrate that PCR testing of formalin-fixed tissue, in combination with bacterial culture, may increase the effectiveness of laboratory diagnostic efforts to detect and identify the most common mycobacterial diseases of ruminants. 相似文献
53.
Results show that PuO(2+x), a high-composition (x = 0.27) phase containing Pu(VI), is the stable binary oxide in air. This nonstoichiometric oxide forms by reaction of dioxide with water and by water-catalyzed reaction of dioxide with oxygen. The PuO(2) + H(2)O reaction rate is 0.27 nanomoles per meter squared per hour at 25 degrees C; the activation energy at 25 degrees to 350 degrees C is 39 kilojoules per mole. Slow kinetics and a low lattice parameter-composition dependence for fluorite-related PuO(2+x) are consistent with a failure to observe the phase in earlier studies. Perplexing aspects of plutonium oxide chemistry can now be explained. 相似文献
54.
1. An experimental rig, designed and built to simulate conditions found in commercial poultry chilling systems, was used to investigate the effects of varying air temperature and chilling duration, and the effect of chlorinated water sprays, on the microbial load present on the skin and in the body cavity of freshly eviscerated poultry carcases; deep muscle and skin temperatures were monitored during chilling at three different temperatures. 2. During dry chilling for 2 h, total viable microbe counts (TVC) and counts of coliforms and pseudomonads from the body cavity fell by between half and one log unit; smaller reductions were observed in samples from the breast skin. 3. The situation changed when chlorinated water sprays (50, 100 or 250 ppm available chlorine) were applied for the first hour of chilling; spraying carcases enhanced the reduction in numbers on the skin; the effect was most pronounced with 250 ppm chlorine; conversely in the body cavity, the general effects of sprays was to increase contamination by up to one log unit. 4. There was no evidence that sprays increased the rate of chilling. 5. When carcases were held overnight in the rig at 11 degrees C after chilling, microbe counts on dry-chilled carcases remained stable, but increased on carcases that had been sprayed with chlorinated water. 相似文献
55.
The southern states produce large numbers of beef calves that are generally weaned and sold in autumn. Keeping calves in this region beyond weaning to graze high-quality forages through a stocker cattle phase could improve profitability. Autumn-weaned Angus crossbred steers were allocated by breeding and weight to four forage systems that began in mid-November and continued through mid-October as follows: System 1, tall fescue (Festuca arundinacea Schreb.) and Kentucky bluegrass (Poa pratensis L.)-white clover (Trifolium repens L.); System 2, tall fescue, caucasian bluestem (Bothriochloa caucasica [Trin.] C. E. Hubbard) and tall fescue-red clover (Trifolium pratense L.); System 3, orchardgrass-alfalfa and bluegrass-white clover; and System 4, rye (Secale cereale L.), soybeans (Glycine max)-foxtail millet (Setaria italica), and bluegrass-white clover. All steers were supplemented with hay or silage previously cut from their respective systems when forage for grazing was limited. System 2 which used stockpiled tall fescue for winter grazing and caucasian bluestem for summer forage plus fescuered clover for hay and grazing in a three-paddock system, resulted in greater (P < .01) gain per hectare and per steer, more grazing days, and reduced stored forage requirements and produced more surplus feed than the other systems tested. Gains per hectare for Systems 1 through 4 were 454, 554, 472, and 487 kg (SE = 18), respectively. Harvested forage from Systems 1, 2, and 3 met needs for stored forages but System 4 required additional "purchased" hay. Stored forage was fed for 61, 38, 112, or 104 d for Systems 1 through 4, respectively. Within the physio-climatic region of this experiment, a simple three-paddock system based on cool- and warm-season perennial forages could improve beef production per unit of land area while reducing inputs of labor and equipment. 相似文献
56.
Christiansen JS Hottinger HA Allen L Phillips L Aronson LR 《Journal of the American Animal Hospital Association》2000,36(5):385-389
Hepatic microvascular dysplasia (HMD) is a disease involving a microscopic shunting of blood through the liver without the presence of a macroscopic portosystemic shunt (PSS). Data was collected from medical records and telephone conversations with referring veterinarians and owners of 24 dogs diagnosed with HMD. Criteria for diagnosis included histopathological evidence of microvascular dysplasia on hepatic biopsy as well as surgical exploration and a normal mesenteric portogram to rule out a macroscopic PSS. Dogs with HMD frequently have less severe clinical signs and a better long-term prognosis than do those with a PSS that are managed medically. 相似文献
57.
Bruce K Wobeser Beverly A Kidney Barbara E Powers Stephen J Withrow Monique N Mayer Maria T Spinato Andrew L Allen 《Journal of veterinary diagnostic investigation》2007,19(4):439-443
Agreement among pathologists interpreting histologic specimens is an area of interest within human pathology, but little work in this area has been reported in the veterinary literature. Agreement among pathologists evaluating routine histologic sections of amputated digits from cats and dogs submitted to multiple diagnostic centers was examined. Histologic sections from surgical specimens were reviewed in a blinded fashion by two pathologists, and a comparison to the original diagnosis, as stated in the diagnostic report, was recorded. A total of 513 cases were reviewed, and complete agreement was reached in 409 (79.7%). Of the 104 instances of disagreement, 77 (74.0%) were considered to be of clinical significance. The diagnosis of keratoacanthoma was disagreed with in 19 of 21 diagnoses (90.4%). No other individual diagnosis was similarly disputed. The overall level of disagreement is large and is similar to that reported in human pathology and suggests that further study of this issue would be useful in veterinary pathology. 相似文献
58.
John M Sykes Michael M Garner Leah L Greer Nancy P Lung Rob L Coke Frank Ridgley Mitch Bush Richard J Montali Ben Okimoto Robert Schmidt Jack L Allen Bruce A Rideout Patricia A Pesavento Edward C Ramsay 《Journal of zoo and wildlife medicine》2007,38(2):300-308
Oral eosinophilic granulomas were diagnosed in 16 tigers (Panthera tigris). All lesions were located on the hard or soft palate and typically consisted of flat or slightly raised circular ulcers. Histologic features of these lesions were essentially identical to those seen in oral eosinophilic granulomas of domestic cats and dogs. No clinical signs were noted in eight cases, though various degrees of inappetence, excessive salivation, and dysphagia were noted in the other eight tigers. Six cases were not treated. Treatment for the remaining 10 cases centered on corticosteroids and additional treatments included surgical removal, cryotherapy, antibiotics, and chlorpheniramine. Treatment with corticosteroids did appear to be effective in some cases, though lesions would worsen after cessation of therapy and no cases were cured. In addition, three cases developed complications possibly related to this corticosteroid therapy. The etiology of these lesions remains unknown, though an underlying allergic condition is likely. 相似文献
59.
Yonow T Brewster CC Allen JC Meltzer MI 《The Onderstepoort journal of veterinary research》1998,65(4):263-273
We present a simple model of the dynamics of heartwater that we use to explore and better understand various aspects of this disease. We adapted the Ross-Macdonald model for malaria epidemiology so that we could consider both host and vector populations, and evaluate the interactions between the two. We then use two more biologically detailed models to examine heartwater epidemiology. The first includes a carrier state and host mortality, and the second includes density dependence. The results from all three models indicate that a stable equilibrium with high disease levels is probably the standard situation for heartwater (R0 between 5.7 and 22.4). More than 80% of cattle become infected with heartwater if only 12% of infected tick bites produce an infection in cattle, if tick burdens are as low as only five ticks per host per day, or if tick lifespans are as short as 7 d. A host recovery rate of 30 d results in over 50% of the cattle becoming infected with heartwater. Our analyses indicate that it is quite difficult to prevent the establishment and maintenance of high levels of heartwater in a herd, thereby supporting previous suggestions that any attempts at controlling this disease through stringent tick control regimens are not warranted. 相似文献
60.
1. The performance of six commercial stocks of laying hens fed on a diet composed of home‐produced foodstuffs, not usually used for human consumption, was compared with that of birds fed on a conventional diet.
2. The experimental diet was calculated to be low in energy and methionine and high in fibre by conventional standards. Birds ate up to 12% more of this diet, but the calculated intakes of energy and methionine were less than those of the corresponding controls.
3. White stocks fed on the experimental diet produced seven eggs less per bird than controls while the production of brown stocks was essentially unaffected.
4. The gross efficiency of energy utilisation for egg production was better with the experimental diet. 相似文献