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291.
Without effective pain relief, rubber ring castration of lambs is acutely painful and can also produce chronic pain. The potential of novel, smaller rubber rings to reduce this pain substantially has been investigated. Three groups of eight 2-3 day old lambs, were castrated either with conventional rubber rings (cRR), or novel smaller rubber rings without (nRR) and with local anaesthetic treatment (nRR+La). Behavioural responses and chronic lesions indicative of pain were compared. No major reductions in behavioural responses were produced by castration with nRRs compared with cRRs, but injection of local anaesthetic did reduce these responses significantly. Lambs in all groups developed chronic inflammatory lesions but behavioural evidence of chronic pain was rarely seen. After 28 days, 6/8 necrotic scrotums had been shed by nRR+La; 4/8 by nRR and 2/8 by cRR lambs. The dimensions of rubber rings on necrotic scrotums, suggest that cRRs contracted to their un-stretched size before being shed, whereas nRRs did not. It is concluded that neither of these rubber rings exerted sufficient pressure on trapped nerves to produce anaesthesia rapidly and this may be explained by the physical properties of the tissues at the neck of the scrotum which support the ring.  相似文献   
292.
Objective To describe the histologic features of canine distichiasis using excised tarsoconjunctival specimens that included roots of distichiatic cilia. Procedures The study group included 21 strips of cilia‐bearing tarsoconjunctiva resected from 20 dogs with distichiasis. Eyelid tissue specimens were also collected from 11 euthanized dogs without distichiasis to serve as controls. All flat mount preparations were processed for histologic examination, and serial sections were stained with hematoxylin‐eosin (H&E). A total of 157 slides were examined for the study group to describe the follicles and path of the distichiatic hairs and determine their potential connection with the tarsal glands. A total of 82 slides were examined for the control group. Results In 19 of the 20 dogs with distichiasis, serial sections of the specimens identified anatomic segments of hair follicles located abnormally in the eyelid tarsus and associated with the aberrant cilia. They appeared as hair bulbs adjacent to tarsal glands, middle portions of hair follicles located between sebaceous lobules, and single or multiple hair shafts present within the sebaceous duct. The tarsal glands in the cilia‐bearing tarsoconjunctiva were not different from those of the controls, in which no distichiatic hair bulbs or shafts were observed. Conclusions These results demonstrate that adventitious cilia are not associated with histologic changes of the tarsal glands, and appear to arise from ectopic hair follicles present in the tarsus. Canine distichiasis may result from anomalous regulation of morphogenesis of hair follicles in the mesenchymal tissue of the tarsal plate.  相似文献   
293.
Over the next decades, green infrastructure initiatives such as tree planting campaigns, and ecological restoration will dramatically change the species composition, species distribution and structure of urban forests across the United States. These impending changes are accompanied by a demand for urban public spaces where people can engage in practices such as gleaning, gardening, and livestock production. This article analyzes the institutional framework that undergirds efforts in Seattle, Washington to normalize the production and use of edible landscapes. We focus attention on the role of grassroots fruit gleaning groups and highlight their bridging function between Seattle's agriculture and forestry policy arenas, creating an entry point for re-conceptualizing urban forests as sites of production. We conclude that a vision of urban forests as providers of goods as well as services may provide a more solid foundation for achieving urban sustainability than the current “hands off” approach to urban forest management. Gleaning and gathering in urban wild and cultivated landscapes provides opportunities for inhabitants to steward public natural resources and interact deeply with nature.  相似文献   
294.
295.
Stagonosporopsis andigena and S. crystalliniformis are serious foliage pathogens on potato (Solanum tuberosum) and tomato (Solanum lycopersicum). As both species have been recorded only in the Andes area, S. andigena is listed as an A1 quarantine organism in Europe. The actin region of isolates of Stagonosporopsis and allied species of Boeremia, Didymella, Peyronellaea and Phoma was amplified using generic primers. DNA sequence differences of the actin gene were utilised to develop species-specific real-time (TaqMan) PCR assays for the detection of S. andigena and S. crystalliniformis in leaves of potato or tomato. The specificity of the TaqMan PCR assays was determined on genomic DNA extracted from two S. andigena and two S. crystalliniformis isolates and 16 selected isolates of Stagonosporopsis, Phoma and Boeremia, which are the closest relatives. The validation of the methods developed included the DNA extraction and the TaqMan PCR assays. The performance criteria specificity, analytical sensitivity, reproducibility, repeatability and robustness of the TaqMan PCR assays demonstrated the reliability of both methods for the detection of S. andigena and S. crystalliniformis in leaf material. The TaqMan PCR assays were tested on symptomatic leaves of potato and tomato that were obtained after artificial inoculation of detached leaves with both pathogens under quarantine conditions. In the artificial inoculation experiments both S. andigena and S. crystalliniformis caused leaf infections on potato and tomato.  相似文献   
296.
In a serologic survey of Montana-source weaned calves and yearling cattle, the apparent prevalence of antibodies to Bluetongue virus was 0.68% and 1.26% in 2002 and 2003, respectively, and to Anaplasma marginale at a positive cutoff at 30% inhibition it was 1.82% and 1.35% in 2002 and 2003, and at a positive cutoff at 42% inhibition it was 0.76% and 0.55% in 2002 and 2003, respectively, suggesting that the risk of importing infected animals was very low.  相似文献   
297.
Reduction factors (RFs) for bacterial counts on examiners' hands were compared when performing a standardized equine physical examination, followed by the use of one of 3 hand-hygiene protocols (washing with soap, ethanol gel application, and chlorohexidine-ethanol application). The mean RFs were 1.29 log10 and 1.44 log10 at 2 study sites for the alcohol-gel (62% ethyl alcohol active ingredient) protocols and 1.47 log10 and 1.94 log10 at 2 study sites for the chlorhexidine-alcohol (61% ethyl alcohol plus 1% chlorhexidine active ingredients) protocols, respectively. The RFs were significantly different (P < 0.0001) between the hand-washing group and the other 2 treatment groups (the alcohol-gel and the chlorhexidine-alcohol lotion). The use of alcohol-based gels or chlorhexidine-alcohol hand hygiene protocols must still be proven effective in equine practice settings, but in this study, these protocols were equivalent or superior to hand washing for reduction in bacterial load on the hands of people after they perform routine physical examinations.  相似文献   
298.
There are concerns regarding the safety of feeding raw meat to household pets. This study demonstrated that Salmonella persists in food bowls that are inoculated with Salmonella-containing raw meat. Standard methods of cleaning and disinfection were minimally effective at eliminating Salmonella contamination.  相似文献   
299.
OBJECTIVE: To determine the clinical applications, short and long-term survival, and complications of using transfixation pin casts for treatment of comminuted phalangeal fractures in adult horses. DESIGN: Retrospective case series. ANIMALS: 20 horses. PROCEDURES: Medical records were reviewed to obtain information regarding signalment, fracture location, treatment methods, complications, and short-term survival (discharge from hospital). Long-term follow-up information was obtained via contact with owners or trainers. RESULTS: 12 fractures were in a hind limb, and 8 were in a forelimb. Fourteen fractures occurred in a middle phalanx, and 6 occurred in a proximal phalanx. Eleven fractures were treated with internal fixation combined with transfixation pin casts, and 9 fractures were treated with transfixation pin casts alone. Transfixation pin casts were maintained for a mean of 52 days (median, 49 days; range, 1 to 131 days). Fourteen (70%) horses were discharged from the hospital, whereas 6 (30%) were euthanized during the treatment period. Reasons for euthanasia included secondary fracture of the third metacarpal or metatarsal bone, avascularity of the distal aspect of the limb associated with an open fracture, and displacement of the fracture after transfixation pin cast removal. A significantly greater number of horses was discharged from the hospital when the transfixation pin cast was maintained for > 40 days, compared with those in which the transfixation pin cast was maintained for < 40 days. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that horses should be maintained in a transfixation pin cast for a minimum of 40 days, as this was associated with an increase in short-term survival without an increased risk of catastrophic failure.  相似文献   
300.
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