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Humane strategies for controlling feral cat populations 总被引:1,自引:0,他引:1
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Hall JA Yager J 《The Canadian veterinary journal. La revue veterinaire canadienne》2004,45(10):872, 874-874
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Microbial pathogens that normally inhabit our environment can adapt to thrive inside mammalian hosts. There are six dimorphic fungi that cause disease worldwide, which switch from nonpathogenic molds in soil to pathogenic yeast after spores are inhaled and exposed to elevated temperature. Mechanisms that regulate this switch remain obscure. We show that a hybrid histidine kinase senses host signals and triggers the transition from mold to yeast. The kinase also regulates cell-wall integrity, sporulation, and expression of virulence genes in vivo. This global regulator shapes how dimorphic fungal pathogens adapt to the mammalian host, which has broad implications for treating and preventing systemic fungal disease. 相似文献
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Management factors affecting stereotypies and body condition score in nonracing horses in Prince Edward Island 下载免费PDF全文
Christie JL Hewson CJ Riley CB McNiven MA Dohoo IR Bate LA 《The Canadian veterinary journal. La revue veterinaire canadienne》2006,47(2):136-143
In North America, there are few representative data about the effects of management practices on equine welfare. In a randomized survey of 312 nonracing horses in Prince Edward Island (response rate 68.4%), owners completed a pretested questionnaire and a veterinarian examined each horse. Regression analyses identified factors affecting 2 welfare markers: body condition score (BCS) and stereotypic behavior. Horses' BCSs were high (mean 5.7, on a 9-point scale) and were associated with sex (males had lower BCSs than females; P < 0.001) and examination date (P = 0.052). Prevalences of crib biting, wind sucking, and weaving were 3.8%, 3.8%, and 4.8%, respectively. Age (OR = 1.07, P = 0.08) and hours worked weekly (OR = 1.12, P = 0.03) were risk factors for weaving. Straw bedding (OR = 0.3, P = 0.03), daily hours at pasture (OR = 0.94, P = 0.02), and horse type (drafts and miniatures had a lower risk than light horses; P = 0.12) reduced the risk of horses showing oral stereotypies. Some of these results contradict those of other studies perhaps because of populations concerned. 相似文献
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Biofortification of maize with beta-carotene has the potential to improve vitamin A status in vitamin A deficient populations where maize is a staple crop. Accurate assessment of provitamin A carotenoids in maize must be performed to direct breeding efforts. The objective was to evaluate carotenoid extraction methods and determine essential steps for use in countries growing biofortified maize. The most reproducible method based on coefficient of variation and extraction efficiency was a modification of Kurilich and Juvik (1999). Heat and saponification are required to release carotenoids from biofortified maize and remove oils interfering with chromatographic analysis. For maize samples with high oil content, additional base may be added to ensure complete saponification without compromising results. Degradation of internal standard before carotenoids were released from the maize matrix required the addition of internal standard after heating to prevent overestimation of carotenoids. This modified method works well for lutein, zeaxanthin, beta-cryptoxanthin, alpha-carotene, and beta-carotene. 相似文献
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Injured or sick wild avian species, especially raptors (birds of prey, including hawks, owls, falcons, and eagles), can present different challenges to veterinary students and veterinarians who are trained in companion avian medicine (e.g., parrot medicine). Proper capture and restraint, feeding, housing, and certain diagnostic and treatment techniques involving raptors require different skills, knowledge, and resources than working with parrots. We developed an innovative raptor medicine program that enables students to acquire proficiency in safe capture, restraint, and examination techniques and in common diagnostic and treatment procedures. A self-assessment survey was developed to determine students' confidence and proficiency in 10 procedures taught in the lab. Groups were compared by class status (Year 1 vs. Year 2 and 3) and level of prior raptor experience (non-experienced or experienced). In surveys conducted before and after teaching two sets of raptor training labs, students rated themselves significantly more proficient in all 10 diagnostic and treatment procedures after completing the two raptor laboratories. The greatest improvements were observed in technical skill procedures such as fluid administration, intramuscular injections, cloacal swabs, venipuncture, and bandaging. Our approach to incorporating elective wildlife learning experiences into the veterinary curriculum may be replicable in other veterinary schools, with or without a wildlife rehabilitation program. 相似文献
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Poxvirus infections affecting the skin of cats are extremely rare in North America, in contrast to Europe where cowpox virus is well recognized as an accidental pathogen in cats that hunt small rodents. The virus or viruses responsible for the anecdotal cases in North America have never been characterized. This paper reports a case of raccoonpox infection in a Canadian cat. Biopsy of the initial ulcerative lesion on the forepaw revealed ballooning degeneration of surface and follicular keratinoctyes. Infected cells contained large eosinophilic type A inclusions. Electron microscopic examination revealed virions of an orthopoxvirus, subsequently identified as raccoonpox by polymerase chain reaction and gene sequencing. The cat made a full recovery. 相似文献