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491.
492.
Simple transport medium for the isolation of Chlamydia psittaci from clinical material 总被引:2,自引:0,他引:2
Infectious elementary bodies of Chlamydia psittaci in tissue samples from field cases of enzootic abortion were placed in five different transport media (A to E). In one medium, in the absence of refrigerative storage, the organism remained viable for 30 days and at 4 degrees C for 34 days. This was medium D; it consisted of sucrose (74.6 g/litre), K2HPO4 (1.237 g/litre), L-glutamic acid (0.721 g/litre), fetal calf serum (10 per cent v/v), vancomycin and streptomycin (100 micrograms/ml) and nystatin and gentamicin (50 micrograms/ml). Samples of this transport medium were supplied to veterinary investigation centres throughout the UK. Of 1862 samples submitted for diagnosis of enzootic abortion only 1.55 per cent were so contaminated that chlamydiae could not be detected. This transport medium permits the isolation of C psittaci from clinical material for up to about one month, even in the absence of conventional storage facilities. 相似文献
493.
JW NOBLE JdeB CROSSLEY BD HILL† RJ PIERCE† RA McKENZIE‡ M. DEBRITZ§ AA MORLEY¶ 《Australian veterinary journal》1994,71(7):196-200
Summary Serious incidents of pyrrolizidine alkaloidosis of cattle in 10 herds exposed to the Australian native plant, Senecio lautus (Asteraceae), were seen in central Queensland during 1988–1992. The deaths of 226 cattle were recorded. A mean of 8% of cattle died in affected groups (range 2 to 58%). Sickness and deaths usually occurred some months after access to S lautus. Typically, affected cattle lost body condition to the point of emaciation before dying and had persistent diarrhoea. Some animals developed abnormal behaviour and died after a shorter illness. Liver specimens from affected cattle in all herds contained lesions consistent with pyrrolizidine alkaloidosis. Thin layer chromatography of extracts of blood and liver samples from cattle from 5 herds detected pyrrolic metabolites. The identity of these was confirmed by mass spectroscopy on samples from one herd. Unseasonal autumn and winter rain after a dry summer appeared to favour growth of S lautus at the expense of other pasture species. A subsequent dry period promoted consumption of S lautus and was followed by a cluster of poisoning incidents. 相似文献
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Vaccination of chickens with turkey herpesvirus (HVT) or attenuated Marek's disease herpesvirus (aMDHV) blocked infection with virulent MDHV (VMDHV) for approximately 5 weeks after contact exposure. However, there was no apparent blockage of infection when challenge virus was administered intraabdominally (IA). Evidence for infection with VMDHV was based on viral isolation by in vivo assay or by detecting precipitins to "A" antigen associated with virulent virus. The HVT stimulated production of neutralizing antibody against VMDHV in a high percentage of chickens, whereas the aMDHV was a comparatively poor inducer of such antibody. Despite this difference, both of the vaccinal viruses conferred protection against development of Marek's disease. 相似文献
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Spencer JA Bingham J Heath R Richards B 《The Onderstepoort journal of veterinary research》1999,66(3):251-253
A survey of free-ranging jackals (Canis adustus and Canis mesomelas) in Zimbabwe was conducted to determine the prevalence of serum antibodies to canine distemper virus (CDV), canine parvovirus (CPV) and canine adenovirus type 1 (CAV-1). Sera from 16 Canis adustus and 22 Canis mesomelas were collected from 1990 to 1993 from various regions of Zimbabwe and assayed by means of immunofluorescent techniques. Seroprevalence in C. adustus and C. mesomelas respectively were 50% and 63.6% for CDV, 12.5% and 18.2% for CPV and 37.5 and 9.1 for CAV-1. These results demonstrate that jackals are infected with these viruses and may act as reservoirs of them, although their susceptibility to the viruses is not known. 相似文献
500.