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91.
Secondary bacterial infection is a frequent complication in lesional skin of dogs with immunomodulatory‐responsive lymphocytic–plasmacytic pododermatitis (ImR‐LPP). However, the influence of skin pH and temperature in determining the composition of the cutaneous microflora at lesional sites has not been investigated. The association between ImR‐LPP and pedal skin temperature, pH and Staphylococcus pseudintermedius isolates was thus evaluated. Temperature and pH were measured in 20 dogs with ImR‐LPP and in 30 clinically healthy control dogs, and S. pseudintermedius was cultured from interdigital and palmoplantar swabs in both groups and scored semi‐quantitatively for bacterial growth. In the ImR‐LPP group, mean skin pH was slightly, but significantly, higher at both interdigital and palmoplantar sites. Staphylococcus pseudintermedius was isolated more frequently, and scores for bacterial growth were also significantly higher. However, mean skin temperatures were not significantly different from those in the control group. The isolation of S. pseudintermedius was significantly associated with ImR‐LPP, with the single exception of isolates on Columbia blood agar from the palmoplantar region. However, pH and temperature were not significantly associated with the disease, and were not associated with the isolation of S. pseudintermedius at most sites sampled. Staphylococcus pseudintermedius was not isolated from all feet sampled in dogs with ImR‐LPP. Taken together, these data would suggest that S. pseudintermedius infection is most likely to be a secondary phenomenon in dogs with ImR‐LPP, and that changes in skin pH and temperature are not significant risk factors for this disease.  相似文献   
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Patrick L. Abbott 《CATENA》1981,8(1):223-237
Ancient weathering profiles provide mute evidence of the major climatic regimes that operated in the southern California area during the Cenozoic Era. A tropical climate during part of the Paleocene and Early Eocene caused severe weathering of Jurassic andesitic rocks, Cretaceous granitic rocks and Late Cretaceous and Early Eocene terrigenous rocks. Erosional remnants of this paleosol exist as buried soils up to 30 meters thick and as exhumed soils on some modern hills. The main weathering horizon is overwhelmingly composed of kaolinite with residual quartz grains and minor amounts of iron oxides. This tropical climate was in effect at 35° to 40° north latitude.Late Eocene sedimentary rocks were deposited under a semi-arid climate with 50 to 60 cm of annual rainfall that was concentrated during one season. This interpretation is based on: 1) the dominance of conglomerate and immature sandstone in the Upper Eocene section compared to the relative scarcity of claystone, 2) the immaturity of the clay mineral suite which is dominated by smectite and vermiculite, 3) the presence of fractured clasts presumably split by growth and differential expansion of salts, 4) the multiple caliche beds that individually are up to one meter thick, and 5) the paleohydrology of the fluvial deposits which transported rhyolite gravels over 300 km distance from an eastern bedrock source about 4,000 m high in a river of 1.3 sinuosity with 100 year flood discharges up to 30,000 m3/sec.The extensive marine terraces in San Diego are mantled by relict soils that record composite weathering characteristics from glacial and interglacial climates from Late Pliocene to present. Maximal development of the paleosol includes an ironstone concretion layer (Bir horizon) above an illuvial clay layer (Bt horizon) which rests on an iron- and silicacemented hardpan (Cm horizon).  相似文献   
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Charles Sturt University in New South Wales, Australia, is responding to a national need for veterinarians with the skills and attributes to fulfill roles in rural practice and the large-animal industries. Rural practitioners must competently and confidently handle a range of large animals if they are to build a relationship of mutual trust with clients and deliver effective animal-health services. Training in animal handling begins in the first year of the course with highly structured small-group practical classes involving cattle, horses, sheep, dogs, cats, pigs, poultry, and laboratory animals (rats and mice). Other experiences with animals in the first three years build on basic animal-handling skills while performing other veterinary activities. Students who provide documented evidence of prior animal-handling experiences are admitted, and learning and teaching strategies aim to enhance skills and knowledge. Rigorous examinations use a competency-based approach prior to extramural placements on farms and in veterinary practices. A continuing process of evaluation, review, and refinement will ensure continual improvement and graduate veterinarians with strong skills in animal handling.  相似文献   
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Persistence of MRSA infection   总被引:1,自引:0,他引:1  
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A study was conducted to evaluate and compare the efficacy of two injectable formulations of ivermectin (IVM-1 and IVM-2) at a dose rate of 0.3 mg/kg bodyweight versus placebo in the treatment and control of larval and adult stages of Ascaris suum and Oesophagostomum spp. in experimentally infected pigs. Seventy helminth free pigs were allocated on a liveweight basis to 7 groups each comprising 10 pigs (A-G). Group A served as an untreated control group. Groups B and C were used to investigate the efficacy of both formulations against adult stages of A. suum and Oesophagostomum spp., Groups D and E for efficacy against larval stages of A. suum and Groups F and G for efficacy against larval stages of Oesophagostomum spp. Pigs of groups A, B, C, D and E were infected on Day-0 with 1000 infective A. suum eggs each. Infective larvae of Oesophagostomum spp. (10,000/pig) were given on Day-0 to pigs of Groups F and G and on Day-21 to pigs of Groups A, B and C. Treatment was given to pigs of Group A (saline as placebo) on Day-7 and -28, IVM-1 to pigs of Group F on Day-7, pigs of Group D on Day-14 and pigs of Group B on Day-49. IVM-2 was given to pigs of Group G on Day-7, Group E on Day-28 and Group C on Day-49. Pigs of Groups F and G were sacrificed on Day-28, pigs of Groups A, D and E on Day-49 and pigs of Groups B and C on Day-56. Post mortem worm counts showed the following efficacies: (IVM-1) against larval A. suum 100%, against adult A. suum 94.4%, against larval Oesophagostomum spp. 52.0% and against adult Oesophagostomum spp. 83.0%. (IVM-2) against larval A. suum 100%, against adult A. suum 90.3%, against larval Oesophagostomum spp. 94.0% and against adult Oesophagostomum spp. 94.7%.  相似文献   
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