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481.
Nutrition is a critical component of equine health. Horse owners' knowledge of nutrition is likely to affect their feeding practices. The aim of this study was to survey feeding practices, dietary supplement use, and knowledge about equine nutrition in New England by surveying a subpopulation of horse owners (67/337 or 19.8%) who brought their horses to the Large Animal Hospital at the Cummings School of Veterinary Medicine at Tufts University between July and September 2008. All owners reported feeding hay, with the majority feeding grass or timothy hay. Most owners (96%) reported feeding a concentrate in addition to hay. Approximately 84% of owners reported including at least one dietary supplement in their horse's daily feeding. The most commonly used supplements were chondroprotectives, electrolytes, and multivitamins. Survey questions designed to assess the owner's knowledge of nutrition suggested that many owners may not have a basic understanding of principles of equine nutrition; less than 50% knew the daily water and hay requirements for a horse, and 69% lacked knowledge about the proper use of concentrates in a diet. Most of the surveyed owners consulted multiple sources of information concerning equine nutrition, including veterinarians (n = 36), trainers (n = 27), feed stores (n = 10), and the internet (n = 7). Although the major source of information was the veterinarian, it appears that the communication between horse owners and their veterinarian about optimal feeding practices could be enhanced. This survey demonstrated areas in the veterinarian–client dialog that need to be addressed when evaluating the health and well-being of the horse.  相似文献   
482.
OBJECTIVE: To provide information on the clinical features, diagnosis and treatment of bacterial septic arthritis in dogs. DESIGN: A retrospective study examining case records of all dogs diagnosed with bacterial septic arthritis at Murdoch University Veterinary Hospital between 1988 and 1997. RESULTS: Nineteen dogs were diagnosed with bacterial septic arthritis, which most commonly occurred after surgery involving the stifle joint. Haematogenous infection occurred in only five dogs. Diagnosis was based on clinical signs, joint fluid analysis, radiography, microbiology and/or response to treatment. Chronic lameness was the most common problem at presentation. Analysis of joint fluid invariably revealed large number of nucleated cells, which consisted primarily of neutrophils. In all but one case the neutrophils were nondegenerate. Culture of joint fluid was frequently successful. Staphylococcus spp were the most common bacteria isolated. Treatment involved antimicrobial drugs only in five dogs. Other dogs received antimicrobial drugs in combination with surgical procedures such as joint lavage and removal of nonabsorbable suture material (eight), arthrodesis (two) or amputation (one). Two dogs were euthanased. Most dogs responded well to treatment and were free of signs of septic arthritis at follow-up. CONCLUSION: Bacterial septic arthritis may often be mild and manifest as chronic lameness. Analysis of joint fluid will detect an inflammatory arthropathy but the presence of toxic neutrophils should not be relied on as an indicator of sepsis. Culture of infected joint fluid is likely to be successful if antimicrobials are not given prior to collection and if the sample is inoculated into enrichment broth. Treatment should involve antimicrobial drugs, open-joint lavage and removal of joint prostheses if the infection is associated with previous surgery.  相似文献   
483.
A Rottweiler dog was presented with an 8 week history of hindlimb ataxia. Neurological examination localised the lesion to the cervical spinal cord. Myelography demonstrated dynamic compressive lesions at C5-6 and C6-7 consistent with a diagnosis of caudal cervical spondylomyelopathy. Distraction/stabilisation of both discs was performed using interbody polymethyl methacrylate. Both implants subsequently failed leading to extrusion of the remaining dorsal annulus fibrosus of the C5-6 intervertebral disc and nonambulatory tetraparesis. A ventral slot combined with distraction/stabilisation using screws and polymethyl methacrylate was performed and resulted in nearly full neurological recovery.  相似文献   
484.
A method combining laser ablation cluster formation and vapor-liquid-solid (VLS) growth was developed for the synthesis of semiconductor nanowires. In this process, laser ablation was used to prepare nanometer-diameter catalyst clusters that define the size of wires produced by VLS growth. This approach was used to prepare bulk quantities of uniform single-crystal silicon and germanium nanowires with diameters of 6 to 20 and 3 to 9 nanometers, respectively, and lengths ranging from 1 to 30 micrometers. Studies carried out with different conditions and catalyst materials confirmed the central details of the growth mechanism and suggest that well-established phase diagrams can be used to predict rationally catalyst materials and growth conditions for the preparation of nanowires.  相似文献   
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