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21.
BRUCELLA OVIS INFECTION   总被引:4,自引:0,他引:4  
  相似文献   
22.
Vitamin A deficiency is described in captive lions. Ante mortem diagnosis can either be made by serum analysis or liver biopsy, both of which may be problematic. This study utilised magnetic resonance imaging to identify vitamin A deficiency in lions with relatively mild clinical signs, which could otherwise be attributed to numerous other neurological conditions. Magnetic resonance imaging is a non-invasive, reliable diagnostic tool to demonstrate pathology typically associated with this condition. To accommodate varying lion ages and sizes, a number of cranium and brain measurements were compared with that of the maximum diameter of the occular vitreous humor. Occular ratios of the tentorium cerebelli osseum and occipital bone were most reliable in diagnosing the thickened osseous structures characteristic of hypovitaminosis A. The ratio of maximum:minimum dorsoventral diameter of the C1 spinal cord was also of value.  相似文献   
23.
OBJECTIVE: To compare methods of detecting equine herpesvirus type 1 (EHV1)- and EHV4-specific antibodies in horse sera. SAMPLE POPULATION: 33 acute and convalescent serum samples from experimentally or naturally infected horses after confirmed EHV1 or EHV4 infection. PROCEDURE: For each sample, serum antibody titers against EHV1 and EHV4 were determined by use of virus neutralization (VN) and complement fixation (CF) assays. The ELISA absorbance values for each serum sample were determined against the EHV1 and EHV4 recombinant ELISA antigens. Values obtained for acute and convalescent sera in each assay were compared. RESULTS: Following experimental infection of foals, EHV1 or EHV4 antibodies that were specific for the inoculating virus were detected only by use of the ELISA. Results of VN and CF assays indicated that the foals seroconverted to EHV1 and EHV4 following infection with EHV4 only. After EHV1-induced abortion, myeloencephalitis, or respiratory tract disease, the VN and CF assay results revealed seroconversion to EHV1 and EHV4, whereas results of the ELISA revealed seroconversion to EHV1 only. Similarly, after confirmed EHV4-induced respiratory tract disease, increases in EHV4-specific antibodies were detected only by use of the ELISA with no indication of an increase in EHV1 antibodies. The CF and, to a lesser degree, VN assays revealed that seroconversion to EHV1 and EHV4 occurred between the time of obtaining acute and convalescent serum samples. CONCLUSIONS AND CLINICAL RELEVANCE: The EHV1/EHV4 type-specific antibody ELISA clearly identifies horses that have been infected with EHV1 or EHV4 by use of acute and convalescent sera. Results of VN and CF assays indicate that cross-reactive antibodies greatly limit their use.  相似文献   
24.
Abstract

Extract

Infection by the protozoan parasite Toxoplasma gondii is widespread in sheep in New Zealand and is recognized as the most common cause of intra-uterine infection leading to abortion and stillbirths (Hartley et al., 1954 Hartley, W. J., Jebson, J. L. and McFarlane, D. 1954. New Zealand Type II Abortion in ewes. Aust. vet. J., 30: 216218.  [Google Scholar]; Hartley and Boyes, 1964 Hartley, W. J. and Boyes, B. W. 1964. Incidence of ovine perinatal mortality in New Zealand with particular reference to intra-uterine infections. N.Z. vet. J., 12: 3336. [Taylor &; Francis Online] [Google Scholar]). In view of the prevalence of this infection in New Zealand, trials were set up to investigate some aspects of the epidemiology of this perplexing disease.  相似文献   
25.
Extract

During recent years a specific myopathy has been recognized in lambs in the South Island of New Zealand. In view of the similarity of the lesions of this condition to “stiff lamb disease,” as described by various workers in the U.S.A. and also more recently by Cotchin in Great Britain, it was thought desirable to record the problem as encountered in New Zealand.  相似文献   
26.
The journal     
Extract

At the Annual General Meeting of the New Zealand Veterinary Association in 1951 a motion was carried “that this meeting recommend that a journal be started, and ask Council to investigate the matter from all aspects, and to report to the next Annual General Meeting.” To implement the wishes of the meeting, Council appointed a subcommittee which reported to the Annual General Meeting of 1952. The report, after dealing with costs and publishable material, recommended as follows:—  相似文献   
27.
On the basis of worm counts in naturally infected Angora-X goats, albendazole at either 3.8mg/kg repeated after 24 hours or as a single dose at 7.6mg/kg, was >99% effective in removing adult Ostertagia and Trichostrongylus spp. Small numbers of adult Haemonchus contortus, Cooperia sp. and Chabertia ovina were present in control but not treated animals. The single dose of 7.6mg/kg removed > 99% of adult Oesophagostomum venulosum whereas the repeated dose of 3.8mg/kg removed only 96%.  相似文献   
28.
An inhibitor typing scheme, based on the production of and sensitivity to bacteriocin-like inhibitor substances was used to identify strains of Streptococcus uberis obtained from skin swabs and milk samples of dairy cows. Thirty-nine isolates from one herd were compared, with one isolate examined per site for any sampling day. Eighteen different inhibitor profiles were observed from these isolates. When several isolates were obtained from various skin sites on a cow on the same day, the inhibitor profiles were all different. In three cases, Str. uberis was simultaneously isolated from milk sample and teat surface of the same quarter, but similar inhibitor profiles were only observed for one pair of isolates. Furthermore, when several isolates were obtained by repeated swabbing of a single skin site on a cow on the same day, differences in the inhibitor profiles were again seen. It is likely that numerous strains of Str. uberis are capable of producing clinical mastitis since a comparison of ten isolates obtained from cases of clinical mastitis revealed eight different inhibitor profiles.

Monthly sampling (April–November) of eleven cows revealed that Str. uberis could be isolated from the skin of the abdominal wall, medial thigh, udder and teats, but was not isolated from the rectum of any of the cows. Str. uberis was more frequently isolated from the skin and milk samples during the winter when the cows had been dried off, than during the spring and autumn.  相似文献   
29.
Extract

A great deal of evidence has now accumulated that immunity to helminth infection is acquired following natural exposure. Although this immunity is not absolute, animals that have been exposed to infection and survived are able to tolerate a much heavier intake of infective larvae than animals that have never been exposed.  相似文献   
30.
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