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101.
102.
This report describes a case of neutrophilic dermatosis in a dog, with a number of clinical and pathological similarities to human pyoderma gangrenosum. A seven-year-old, female German shepherd dog with a history of non-erosive idiopathic polyarthritis was presented with severe facial swelling, bilateral erosivoulcerative lesions on the muzzle and multiple, eroded, dermal-subcutaneous nodules on the cranial trunk. Histopathological examination of skin biopsies revealed a necrotising neutrophilic dermatitis. No infectious agents could be detected using specific stains, immunohistochemistry, serology and bacterial aerobic, anaerobic or fungal cultures. A sterile neutrophilic dermatosis resembling human pyoderma gangrenosum was presumptively diagnosed, and the patient showed an excellent response to treatment with prednisone and ciclosporin.  相似文献   
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Nineteen free-ranging maned wolves (Chrysocyon brachyurus) were captured in central Brazil from April through November 2003. Oral cavity examination revealed 34 teeth with crown trauma in twelve animals. Canine teeth were most commonly affected (44.2%), followed by premolar (29.4%) and incisor teeth (26.5%). Trauma to maxillary teeth (67.7%) was more frequent compared with mandibular teeth (32.3 %). The majority of dental fractures were located at the cuspid portion of the crown (56.0%). Slab fractures were the most frequent type (37.0%), followed by horizontal (24.0%), oblique (24.0%) and longitudinal fractures (15.0%). Complicated crown fracture (pulp exposure) was diagnosed in 13 (38.2%) of these teeth while pulpitis noted by tooth discoloration was diagnosed in 8 (23.5%) teeth.  相似文献   
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This study was planned to express the detailed traits of Karayaka sheep reared in Tokat province, also influencing factors on the traits were evaluated. While year effect was significant on 8 weeks weight, scanning weight, fat depth and muscle area, all the evaluated traits including birth weight and muscle depth were significantly affected by season (p < 0.05). Dam age was significant on birth weight (p < 0.05). Birth weight and 8 week weight were significantly affected by sex and birth type. Sex effect has been appeared on muscle depth while birth type effect has been detected on scanning weight (p < 0.05). While the strongest phenotypic correlation coefficient was detected between muscle depth and muscle area, the weakest ones were found between birth weight and scanning traits.  相似文献   
107.
The crayfish plague pathogen (Aphanomyces astaci) can be transmitted through the digestive system of fish, but its dispersal through mammalian and bird digestive tracts has been considered unlikely, and direct experimental evidence remains scarce. We present a small-scale transmission experiment with European otter and American mink fed with infected crayfish, and experiments testing survival of cultures of five A. astaci strains at temperatures corresponding to those inside mammal and bird bodies. The pathogen was neither isolated from predator excrements nor transmitted to susceptible crayfish exposed to excrements. In agar-based artificial media, it occasionally survived for 15 min at 40.5°C and for 45 min at 37.5°C, but not so when incubated at those temperatures for 45 min and 75 min, respectively. The five tested strains differed in resistance to high temperatures, two (of genotype groups E and D) being more susceptible than other three (of groups A, B and D). Their survival to some extent varied when exposed to the same temperature after several weeks or months, suggesting that some yet-unknown factors may influence A. astaci resistance to temperature stress. Overall, we support the notion that passage through the digestive tract of warm-blooded predators makes A. astaci transmission unlikely.  相似文献   
108.
We evaluated the relationship of stocking density to survival, growth performance and fin condition of European perch Perca fluviatilis with hand feeding and self-feeders. Hand-fed perch (body weight 19.1 ± 5.1 g and total length 107 ± 9 mm) were reared at 0.5, 1.0, 1.5 and 2.0 fish/L. Self-feeding perch (body weight 25.4 ± 3.9 g and total length 128 ± 7 mm) were reared at stocking densities of 0.6, 1.0 and 1.4 fish/L. Pond-reared perch served as a comparison group for fin damage assessment. We found no differences in survival rate among stocking densities with either feeding method. Hand-fed fish displayed the highest weight gain and SGR at stocking density of 0.5 fish/L. The self-feeding fish showed a non-linear association of weight gain with stocking density with the highest growth at 1.0 fish/L. Fin length was noticeably greater in pond-reared fish compared with RAS-reared fish regardless of feeding method. In both experiments, fin length relative to standard length showed a negative relationship with stocking density, with pectoral fins showing the greatest effect. Fin condition deteriorated with increasing stocking density, and growth was highest at 0.5 and 1.0 fish/L in hand-fed and self-feeding fish, respectively.  相似文献   
109.
Peach (Prunus persica L.) plants with symptoms of yellowing, reddening, curling and leaf necrosis, premature defoliation and internode shortening were observed in production fields in Jujuy province (Argentina). A phytoplasma was detected by PCR using the universal primer pairs P1/P7 and R16F2n/R16R2 in all the symptomatic samples analysed. The RFLP profile of PCR products, amplified with R16F2n/R16R2 primers, shows that this phytoplasma, named Argentinean Peach Yellows (ArPY), belongs to subgroup 16Sr III-B. The phylogenetic analysis of the 1244 bp 16S rDNA cloned sequence, grouped the ArPY phytoplasma into the X-disease group with a closer relationship with CFSD, PssWB and ChTDIII phytoplasmas. This is the first report of a phytoplasma infecting peach trees in Argentina.  相似文献   
110.
The identification of optimal management strategies for a given species is a major challenge of species conservation. It becomes especially challenging when the environmental conditions are expected to change in the future, and the optimal management applied today may differ from the management that is optimal under the changed conditions (e.g. due to climate change).This study evaluates prospect of a rare plant species endemic to semi-natural grasslands in central Europe, Gentianella praecox subsp. bohemica. The number of populations of this species has declined rapidly in the last 60 years; currently, a conservation action plan has been established in the Czech Republic, where most populations of this species occur. This study uses periodic matrix models to compare different management regimes under different scenarios of climate change and to identify the optimal management in each case.Without management, populations of the species are not able to survive. Flowering individuals can occur for a long time after the cessation of management, but the extinction of the population is inevitable within several decades. Without management, even very large populations (1000 flowering individuals) will go extinct in less than 50 years. Total extinction (including seed bank) will follow several years after observation of the last flowering plant. The most suitable management is mowing and disturbance (by harrowing), which is also the best method for restoration of threatened populations. Mowing is less suitable, but it is fully sufficient for large prospering populations. When managed, even small populations (10–15 flowering individuals) are able to survive. When management is applied, future climate change may have a relatively small impact on the probability of survival of the species. Climate change will, however, increase the extinction probability of very small populations.  相似文献   
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