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121.
Colby MM Johnson YJ 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2002,3(1):31-42
Although geographic information systems (GIS) have been used in many disciplines, the available technology in planning and decision support has only recently begun to be used in intensive animal production, in areas such as confined animal feeding operations. GIS-based planning and decision support systems have the potential to enhance many aspects of intensive animal production, such as disease monitoring and prevention, emergency management and nutrient waste disposal. Current uses of GIS in animal production are reviewed. Potential uses are illustrated using the example of the poultry industry on the Delmarva Peninsula, USA. 相似文献
122.
Hinton LE McLoughlin MA Johnson SE Weisbrode SE 《Journal of the American Animal Hospital Association》2002,38(2):176-187
The records of 23 dogs and cats diagnosed with spontaneous gastroduodenal perforation (GDP) were retrospectively reviewed. Survival was 63% in dogs and 14% in cats. Rottweilers <5 years of age were overrepresented. Clinical evidence of gastrointestinal bleeding was common in dogs but not in cats. Shock was an uncommon presenting condition in dogs and was not closely linked to outcome. In fact, progression of an ulcerating lesion to GDP was not associated with marked changes in symptoms exhibited by many patients in this study. Most GDPs were associated with histopathological evidence of subacute or chronic peritoneal reaction at the time of diagnosis. This suggests that diagnostic methods employed lacked sensitivity in identifying early perforating lesions, and that dramatic signs of acute abdomen following gastroduodenal perforation may not be as common as was previously thought. 相似文献
123.
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
124.
Ramos-Vara JA Miller MA Johnson GC Turnquist SE Kreeger JM Watson GL 《Veterinary pathology》2002,39(1):127-132
Immunohistochemistry, using a monoclonal antibody to Melan A and a polyclonal antibody to S100 protein, was applied to 48 formalin-fixed, paraffin-embedded specimens of feline melanoma. Forty-two cutaneous, three oral, one mucocutaneous, and two metastatic melanomas comprised the tumors. Thirty-two tumors (67%) were positive for Melan A and 42 (87.5%) were positive for S100. All but one of the tumors that were positive for Melan A were also positive for S100. S100 was detected in 11 of 16 tumors that were negative for Melan A. Seventy-five percent (9 of 12) of amelanotic melanomas were negative for Melan A. Normal adrenal cortex, the cerebellum, and the skin had cells that were positive for Melan A. Sebaceous adenoma was the only nonmelanocytic tumor examined that reacted with antibody to Melan A. Although less sensitive than S100 protein, Melan A is more specific for melanoma and is useful in differentiating feline cutaneous melanoma from the more common pigmented basal cell tumor. 相似文献
125.
126.
Hierarchical Bayesian model for prevalence inferences and determination of a country's status for an animal pathogen 总被引:2,自引:0,他引:2
Certification that a country, region or state is "free" from a pathogen or has a prevalence less than a threshold value has implications for trade in animals and animal products. We develop a Bayesian model for assessment of (i) the probability that a country is "free" of or has an animal pathogen, (ii) the proportion of infected herds in an infected country, and (iii) the within-herd prevalence in infected herds. The model uses test results from animals sampled in a two-stage cluster sample of herds within a country. Model parameters are estimated using modern Markov-chain Monte Carlo methods. We demonstrate our approach using published data from surveys of Newcastle disease and porcine reproductive and respiratory syndrome in Switzerland, and for three simulated data sets. 相似文献
127.
Johnson CR Baird AN Baird DK Wenzel JG 《Journal of the American Veterinary Medical Association》2000,216(8):1291-1293
OBJECTIVE: To determine clinical and radiographic findings, treatment, and outcome for llamas with long-bone fractures. DESIGN: Retrospective study. ANIMALS: 6 llamas. PROCEDURE: Medical records of llamas admitted between 1993 and 1998 because of long-bone fractures were reviewed. Data collected included age, sex, type of fracture, method of fracture repair, and postoperative complications. The Fisher exact test was used to compare age and sex of the llamas with long-bone fractures with those of the hospital population of llamas. All owners were contacted by telephone to determine perceived postoperative problems and whether the llamas were able to perform as expected. RESULTS: Mean age was 160.8 days (range, 23 to 365 days). There was 1 male and 5 females. Fractures were more likely to occur in young llamas (< or = 1 year old) than in adults. Five of the fractures were attributed to traumatic episodes. Long bones affected included the tibia (n = 2), radius (2), femur (1), and humerus (1). Internal fixation with lag screws, plating, or both was performed on fractures of all llamas except 1; that llama was treated by use of confinement to a stall. None of the llamas had intraoperative complications, but postoperative complications were reported in 2 llamas. All fractures healed eventually, and clients were pleased with outcomes. CONCLUSIONS AND CLINICAL RELEVANCE: Long-bone fractures in llamas are uncommon. Several types of long bone fractures can be successfully repaired by use of internal fixation, resulting in few complications and minimal convalescent time. 相似文献
128.
OBJECTIVE: To identify factors affecting radial alignment after oblique corrective osteotomy stabilized with a type II external fixator and to evaluate the results of this treatment for antebrachial growth deformities. STUDY DESIGN: Retrospective study SAMPLE POPULATION: Twenty-eight dogs with unilateral antebrachial growth deformities treated with acute corrective osteotomy stabilized with a type II external fixator. METHODS: Medical records and preoperative and postoperative radiographs of the affected and contralateral limb were reviewed. Cause of deformity, age, weight, and gender were recorded. Radial length, varus/valgus angulation, and cranial/caudal angulation were measured from radiographs of the treated and contralateral limbs. Preoperative and postoperative angulation and length discrepancy were compared between affected and contralateral limbs. RESULTS: Correction of varus/valgus angle discrepancy was achieved by using acute corrective osteotomy stabilized with type II external skeletal fixation. No significant change was noted for correction of cranial/caudal angle discrepancy or length discrepancy between the affected and control limb. CLINICAL RELEVANCE: Varus/valgus angle deformities can be treated successfully with type III external fixation after oblique corrective osteotomy. Patients with significant length or cranial/caudal angle discrepancies or both that negatively impact function may require the use of hinged circular fixators or other dynamic techniques to achieve adequate correction. 相似文献
129.
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
130.
Paracox anticoccidial vaccine was administered to a 7-day-old flock of commercial broiler breeder stock subsequently reared to point-of-lay in the same house. For comparison, three subgroups of another flock of broiler breeders were also vaccinated with Paracox at 7 days of age, reared to 42 days and then transferred to new litter on another farm until point-of-lay. The first subgroup received no further treatment, but the second and third each received a second vaccination with Paracox, either immediately after transfer to the new litter or 42 days after transfer. Using an Eimeria necatrix model, protective immunity was demonstrated by virulent challenge of samples of birds from all groups by the age of 37–40 days (30–33 days after the first vaccination), and was maintained to at least 122–125 days of age, whether the birds remained on the same litter or were transferred to another farm, and whether they received one or two anticoccidial vaccinations. Therefore, there is no disadvantage in transferring birds onto new litter 35 days after a single Paracox vaccination, nor is there any advantage in giving a second vaccination after such a transfer. Vaccinated birds seeded the new litter with oocysts, despite being clinically immune to coccidiosis. A supplementary laboratory experiment showed that birds vaccinated at 8 days of age passed almost no oocysts after a second vaccination at 43 days of age. This indicated that they were not only protected against clinical coccidiosis, but were almost solidly immune to a homologous infection 5 weeks after a single vaccination. Nevertheless, oocysts appeared in the litter of all four groups of commercial breeders throughout the trial, showing that wild-type heterologous infections occurred whether the birds were transferred to new litter or not, but these did not overwhelm the acquired protective immunity and cause clinical coccidiosis. 相似文献