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271.
Cook AG Maxwell VB Donaldson LL Parker NA Ward DL Morrow JK 《Journal of the American Veterinary Medical Association》2002,221(2):208-211
OBJECTIVE: To determine whether antibodies against Sarcocystis neurona could be detected in CSF from clinically normal neonatal (2 to 7 days old) and young (2 to 3 months old) foals. DESIGN: Prospective study. ANIMALS: 15 clinically normal neonatal Thoroughbred foals. PROCEDURE: Serum and CSF samples were obtained from foals at 2 to 7 days of age and tested for antibodies against S. neurona by means of western blotting. Serum samples from the mares were also tested for antibodies against S. neurona. Additional CSF and blood samples were obtained from 5 foals between 13 and 41 days after birth and between 62 and 90 days after birth. RESULTS: Antibodies against S. neurona were detected in serum from 13 mares and their foals; antibodies against S. neurona were detected in CSF from 12 of these 13 foals. Degree of immunoreactivity in serum and CSF decreased over time, and antibodies against S. neurona were no longer detected in CSF from 2 foals 83 and 84 days after birth. However, antibodies could still be detected in CSF from the other 3 foals between 62 and 90 days after birth. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that antibodies against S. neurona can be detected in CSF from clinically normal neonatal (2 to 7 days old) foals born to seropositive mares. This suggests that western blotting of CSF cannot be reliably used to diagnose equine protozoal myeloencephalitis in foals < 3 months of age born to seropositive mares. 相似文献
272.
OBJECTIVE: To determine the status of rural veterinary services in Western Australia. PROCEDURE: Two questionnaires were mailed to eligible, registered veterinary surgeons in Western Australia in 2006. The first was mailed to government veterinarians and the second to private practitioners in rural practice. Part A presents the replies from government veterinary officers and Part B the replies from rural practitioners. Replies were transferred to Microsoft Excel for analysis. RESULTS: Sixty-seven per cent of government veterinary officers responded to the questionnaire. Eighty per cent of these had been in the service for 20 years or more and their average age was 54. Work with sheep and beef cattle occupied 75% of their time, with dairy cattle receiving 10% and pigs and poultry less than 10%. The majority of respondents reported changes in the attitude of farmers to the service as a result of rural recessions and the decision to make a direct charge for government veterinary services. Although most respondents thought that the government veterinary service would continue in the future there were differences of opinion as to what form that would take. CONCLUSION: Government veterinary services in Western Australia are undergoing major changes, with the service decreasing in size and scope. Recently the Department of Agriculture has been renamed the Department of Agriculture and Food and it is likely that the role of its veterinary officers will change accordingly. 相似文献
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Andrew T. SMITH BADINGQIUYING Maxwell C. WILSON Brigitte W. HOGAN 《Integrative zoology》2019,14(1):87-103
Understanding a species' functional traits allows for a directed and productive perspective on the role a species plays in nature, and thus its relative importance to conservation planning. The functional‐trait ecology of the plateau pika Ochotona curzoniae is examined to better understand the resilience and sustainability of the high alpine grasslands of the Qinghai–Tibetan Plateau (QTP). The key functional traits of plateau pikas are their abundance and behavior of digging extensive burrow systems. Plateau pikas have been poisoned over a significant part of their original geographic distribution across the QTP, allowing comparison of ecological communities with and without pikas. Nearly all mammalian and avian carnivores, most of which are obligate predators on pikas, have been lost in regions where pikas have been poisoned. Most endemic birds on the QTP nest in pika burrows; when pikas are poisoned, burrows collapse, and these birds are greatly reduced in number. Due to the biopedturbation resulting from their burrows, regional plant species richness is higher in areas with pikas than without. The presence of pika burrows allows higher rates of infiltration during heavy monsoon rains compared to poisoned areas, possibly mitigating runoff and the potential for serious downslope erosion and flooding. Thus, the functional traits of plateau pikas enhance native biodiversity and other important ecosystem functions; these traits are irreplaceable. As plateau pikas are not natural colonizers, active re‐introduction programs are needed to restore pikas to areas from which they have been poisoned to restore the important functional ecological traits of pikas. 相似文献
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1. The plasma viscosity values of normal commercial broiler and layer strains of chicken were measured in relation to age and sex.
2. In both broilers and layers plasma viscosity values decreased at 2 weeks of age; probably reflecting the period of change from maternal plasma protein to the bird's self‐synthesised proteins.
3. There was a progressive rise in plasma viscosity in both strains and sexes with age. The increase was greatest in female layers at 17 weeks of age before lay.
4. There was no overall significant difference in viscosity values between fresh and frozen‐stored plasma samples. 相似文献
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ABSTRACT Bean golden mosaic geminivirus (BGMV) is the single most devastating virus of common beans in the tropical and subtropical Americas and the Caribbean Basin. The BGMV from Brazil, named BGMV-BZ, is considered distinct from BGMV-PR isolates from Puerto Rico, Guatemala, and the Dominican Republic because of DNA sequence data, the ability to form pseudorecombinants, and mechanical transmissibility properties. In bean-growing areas of Brazil, samples were collected from beans, lima beans, and the weed Leonurus sibiricus displaying typical symptoms of infection by geminiviruses. Viral DNA fragments comprising part of the rep gene, the common region, and part of the cp gene were amplified by polymerase chain reaction, cloned, and sequenced. The bean samples had geminivirus with sequences nearly identical to that of BGMV-BZ collected in Goiania, state of Goiás, in 1986. The sample from lima bean contained a new species of geminivirus that induces symptoms similar to those induced by BGMV-BZ and was named lima bean golden mosaic virus (LBGMV-BR). While all sequences from bean samples clustered with BGMV-BZ, the sequence from the lima bean isolate stood alone. A mixed infection with abutilon mosaic geminivirus was also found in a single sample from the state of S?o Paulo. DNA sequence comparisons indicate that the virus isolate from L. sibiricus represents a new geminivirus species, designated here as leonurus mosaic virus. 相似文献
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