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An attenuated strain of Treponema hyodysenteriae was used to immunise 18 pigs in three experiments. Live attenuated spirochaetes were dosed orally and injected intra-peritoneally, and killed spirochaetes were injected intramuscularly with adjuvant. The vaccinated pigs, which developed high serum agglutination titres against T hyodysenteriae, and 18 unvaccinated litter-mates were repeatedly challenged with virulent T hyodysenteriae. Nine vaccinated pigs and 16 control pigs developed typical swine dysentery. 相似文献
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Cell Adherence Reactions in Lungworm (Protostrongylus) Infections of the Rocky Mountain Bighorn Sheep 下载免费PDF全文
The immunological response of captive naturally-infected Rocky Mountain bighorn sheep to the lungworm, Protostrongylus stilesi, was examined throughout the seasonal cycle of parasite activity using a cell adherence assay for circulating antibody. The net effect of all stable serum factors on cell adherence was examined by exposure of normal cells to larvae in the presence of test serum (decomplemented-serum test). Homocytotropic antibody was examined by exposure of washed normal cells to larvae after passive sensitization with serum from infected animals (washed-cell test). Although the washed-cell test did not show a clear association with parasite activity, the net ability of sera to promote adherence showed a significant increase during periods of elevated Protostrongylus activity. Fecal counts of Muellerius, Nematorirus and coccidia were not associated with the results of either assay. Significant differences among animals were detected only for the washed-cell test when the effects of parasitism were considered. 相似文献
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Mellanby RJ Rhind SM Bell C Shaw DJ Gifford J Fennell D Manser C Spratt DP Wright MJ Zago S Hudson NP 《The Veterinary record》2011,168(23):616
The perceptions of veterinarians and small animal (SA) clients on what attributes constitute 'a good veterinarian' were examined by a questionnaire survey. The respondents were asked to record how important they considered 20 attributes for a veterinary surgeon to have on a five-point scale from 'not at all important' to 'very important'. In addition, they were asked to list which attributes they considered to be the three most important attributes in a veterinary surgeon; finally, they were asked whether there were any additional attributes that they considered to be highly desirable in a veterinary surgeon. In total, 407 SA clients, 243 SA veterinarians and 61 non-SA veterinarians completed the questionnaire. There were significant differences in the proportion of clients who considered an attribute to be 'very important' compared with SA veterinarians for 12 of the 20 attributes (P<0.005). A larger proportion of clients considered 'confidence', 'knowledge about veterinary medicine and surgery', 'cleanliness', 'good at explaining technical terms', 'patience', 'clear about cost of treatment', 'ability to work in a team', 'honesty', 'politeness', 'decisiveness', 'good with animals' and 'good practical skills' to be 'very important' attributes than the SA veterinarians; a larger proportion of SA veterinarians considered 'good communication skills' to be a 'very important' attribute than the clients. 相似文献
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Kurobe T MacConnell E Hudson C McDowell TS Mardones FO Hedrick RP 《Journal of aquatic animal health》2011,23(1):9-18
Iridovirus infections of the integument were associated with disease and mortality among hatchery-reared populations of juvenile pallid sturgeon Scaphirhynchus albus and shovelnose sturgeon S. platorynchus from the Missouri River. Virus-infected cells in the integument of fins and body were greatly enlarged, possessed pleomorphic and eccentric nuclei, and exhibited an amphophilic to eosinophilic staining of the cytoplasm in hematoxylin-and-eosin-stained sections. Virus particles found in the host cell cytoplasm were composed of an outer hexagonal capsid measuring 254 nm in diameter and surrounding a dense nucleoid. Despite numerous attempts, the virus could not be propagated on routine cell lines used in fish viral diagnostics or from established cell lines from white sturgeon Acipenser transmontanus, pallid sturgeon, or shovelnose sturgeon. Bath exposures of healthy juvenile pallid sturgeon to a crude extract or a 0.45-microm-filtered extract from the fins of infected fish resulted in transmission of the virus and mortality. At water temperatures of 15 degrees C, the first deaths occurred at approximately 1 month; mortality peaked between 50 and 60 d postexposure, after which surviving fish recovered. Presence of the virus was confirmed among dead and moribund pallid sturgeon by both histology and detection of viral DNA by polymerase chain reaction methods. Feeding of infected tissues and cohabitation with virus-infected shovelnose sturgeon also resulted in successful virus transmission to juvenile pallid sturgeon. Virus infections among experimentally exposed pallid sturgeon that recovered from clinical episodes persisted for at least 8.5 months, and these apparently healthy fish transmitted the virus and disease to juvenile pallid sturgeon by cohabitation. The newly described Missouri River sturgeon iridovirus (MRSIV) as found in pallid sturgeon and shovelnose sturgeon shares many properties with a group of iridoviruses associated with serious skin and gill infections in several species of sturgeon. 相似文献
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