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51.
In the Spring of 2009, a veterinarian reported suspected classical swine fever (CSF) on a multiplier pig farm in the southern part of The Netherlands (close to the Belgian border). Over a 5-week period there had been a number of sick sows and an excessively high percentage of stillborn and preterm piglets. Sick animals were treated with anti-inflammatory drugs and antibiotics, but did not respond as well as anticipated. A visiting specialist team from the Food Safety Authority could not exclude CSF as the cause of the clinical problems and sent blood samples to the reference laboratory in Lelystad for a PCR test on CSF antigen. Fortunately, test results obtained 6 hours later were negative for CSF, and the disease control measures were lifted. It later appeared that porcine reproductive and respiratory syndrome (PRRSV) might have been responsible for the problems. But what if CSF had caused the clinical problems? A CSF-transmission model was used to simulate CSF outbreaks dependent on the duration of the high-risk period (HRP). As the duration of the HRP increased, there was an exponential growth in the number of pig farms infected during this period. Simulations also showed that with a longer HRP, the virus spread over greater distances from the source herd. It was also investigated whether a possible CSF outbreak could be detected on the basis of an increased mortality and hence increased number of cadavers sent to a rendering plant. However, the calculated mortality incidence was not sensitive enough to serve as an alarm signal. It is recommended that CSF-exclusion diagnostics be used much earlier in similar clinical situations on pig farms.  相似文献   
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The metabolism of α-pinene, a major monoterpene in Pinus spp. in the United States, has been examined utilizing microsomal fractions from larval and adult Dendroctonus terebrans and rat liver. Under hydroxylating conditions, both insect and rat liver microsomes convert α-pinene into α-pinene oxide and several other undentified products. α-Pinene oxide was identified by mass spectrometry. α-Pinene is an inducer of cytochrome P-450 in rat liver microsomes and its effect on the pattern of α-pinene metabolism is very similar to β-naphthoflavone. No increase in cytochrome P-450 was observed when insects were treated with α-pinene; however, the quantity of α-pinene metabolic products was increased by α-pinene pretreatment. The role of cytochrome P-450 linked reactions in the production of insect pheromones via the α-pinene epoxide intermediate is discussed.  相似文献   
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Strains of Xanthomonas campestris pv. vignicola (Xcv), isolated from cowpea leaves with blight or minute pustules and collected from various geographic areas, were selected on the basis of pathological and physiological features. All strains were analyzed for genotypic markers by two methods: ribotyping with EcoRI endonuclease, and RFLP analysis with a plasmid probe (pthB) containing a gene required for pathogenicity from Xanthomonas campestris pv. manihotis. Ribotyping revealed a unique pattern for all the strains that corresponded to the previously described ribotype rRNA7. Based on polymorphism detected by pthB among Xcv strains, nine haplotypes were defined. The observed genetic variation was independent of the geographic origin of the strains and of pathogenic variation. Some haplotypes were widely distributed, whereas others were localized. In some cases, we could differentiate strains isolated from blight symptoms and pustules according to haplotypic composition. However, in most cases, no significant differences were observed. Our results and the previous pathogenic and biochemical characterizations suggest that the strains isolated from leaves with blight symptoms or minute pustules belong to the same pathovar. We provide information on pathogen diversity that can be used to identify and characterize resistant germplasm.  相似文献   
55.
During the last two decades bacterial strains associated with necrotic leaf spots of pepper and tomato fruit spots were collected in Serbia. Twenty-eight strains isolated from pepper and six from tomato were characterized. A study of their physiological and pathological characteristics, and fatty acid composition analysis revealed that all of the strains belong to Xanthomonas campestris pv. vesicatoria. Being non-amylolytic and non-pectolytic, pathogenic on pepper but not on tomato, containing lower amounts of fatty acid 15 : 0 ante–iso, the pepper strains were designated as members of the A group of X. campestris pv. vesicatoria. However, the tomato strains hydrolyzed starch and pectate, caused compatible reactions on tomato but not on pepper, had higher percent of 15 : 0 ante–iso fatty acid, and were classified into B phenotypic group and identified as X. vesicatoria. PCR primers were developed which amplified conserved DNA regions related to the hrp genes of different strains of X. campestris pv. vesicatoria associated with pepper and tomato. Restriction analysis of the PCR product resulted in different patterns and enabled grouping of the strains into four groups. When xanthomonads isolated from pepper and tomato in Serbia were analyzed, they clustered into two groups corresponding to the grouping based on their physiological and pathological characteristics. According to the reaction of pepper and tomato differential varieties, the strains from pepper belong to races P7 and P8 and tomato strains belong to the race T2. All strains were sensitive to copper and streptomycin. Advantages and disadvantages of various bacterial spot management practices are discussed.  相似文献   
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The objective of this study was to confirm that weight loss after treatment with mitratapide (Yarvitan®) is loss of adipose tissue. Obese dogs were treated with the recommended treatment schedule of mitratapide. Dual-energy X-ray absorptiometry (DEXA) was done before and after the treatment schedule. Body weight, feed consumption and pelvic circumference were recorded and a glucose tolerance test was performed. Dual-energy X-ray absorptiometry measurements showed an impressive loss of fat tissue, corresponding to a mean loss of approximately 41.6% of the body fat mass recorded before treatment. After treatment with mitratapide, the mean body fat percentage had returned within the normal range. At the end of the study, the dogs had lost on average 14.2% of their body weight and 15.2% of their pelvic circumference compared to baseline. The results also suggest that losing weight with mitratapide might help to reverse insulin resistance.  相似文献   
57.
In October 2004, 41 goats > 2 years old from a Saanen dairy goat herd located in Purranque County, 10th Region, Chile, were sampled and tested for paratuberculosis. While collecting samples it was observed that several goats were thin and emaciated. One goat was sufficiently debilitated to warrant humane euthanasia. This animal was brought to the Veterinary School at the Universidad Austral de Chile for necropsy. The goat selected for necropsy was a 12-year-old doe. The animal showed classical clinical signs of caprine paratuberculosis: emaciation despite willingness to eat, dry and rough hair coat, and no evidence of diarrhea. Gross pathology and histopathology of the necropsied goat were consistent with paucibacillary paratuberculosis. Bacteriology, serology, and PCR confirmed the diagnosis. This is the first published report of goat paratuberculosis in Chile confirming a case of caprine paucibacillary paratuberculosis.  相似文献   
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