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1.
H Ungar-Waron R Paz V Shkap H Bin E Pipano 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1991,38(7):492-496
Polyclonal bovine IgM-rheumatoid factors (IgM-RFs) were examined in sera of cattle immunized against babesiosis. An enzyme-linked immunosorbent assay (ELISA) was used enabling rapid screening of serum samples. Results obtained indicate a rise of serum IgM-RF levels with age in healthy bovines. However when animals of similar age and pertaining to the same herd were examined, levels of serum IgM-RF exhibited a wide distribution range. Mean values in 60 sera of 2 yrs old clinically healthy heifers originating from a single herd were of 452.60 +/- 201.26 e.u. at 1 in 1,000 serum dilution and of 202.37 +/- 137.86 e.u. at 1 in 4,000 serum dilution. In a herd where repeated vaccination of dams against babesiosis was carried out 3 to 6 weeks before delivery either with live Babesia bovis parasites or soluble antigens of in vitro grown organisms, no significant differences in mean IgM-RF values were found between revaccinated animals and a control group. Nor did the mean values of serum IgM-RF of calves born to the respective groups of dams exhibit significant differences. It thus appears that immunization of healthy cattle against this parasite does not affect mean serum IgM-RF levels. 相似文献
2.
A survey for the prevalence of antibodies to Hepatozoon canis and for intraneutrophilic H. canis gametocytes in the peripheral blood neutrophils of dogs in Israel showed that 33.1% were seropositive, while only 1% of the dogs sampled had detectable parasites in their blood smears. Exposure to H. canis is widespread but it appears that most infected dogs undergo a subclinical infection and only a small proportion develop clinical disease.Abbreviations IFAT
indirect fluorescent antibody test 相似文献
3.
Molad T Mazuz ML Fleiderovitz L Fish L Savitsky I Krigel Y Leibovitz B Molloy J Jongejan F Shkap V 《Veterinary microbiology》2006,113(1-2):55-62
A reverse line blot hybridization (RLB) one-stage nested PCR (nPCR) for Anaplasma centrale and a nested PCR for Anaplasma marginale were used to detect infected cattle grazing within an endemic region in Israel. A novel set of PCR primers and oligonucleotide probes based on a 16S ribosomal RNA gene was designed for RLB detection of both Anaplasma species, and the performance of the molecular assays compared. The immunofluorescent antibody test (IFA) was used to detect antibodies to both Anaplasma species, whereas, a highly sensitive and specific competitive enzyme-linked immunosorbent assay (cELISA) was used to detect antibodies in A. centrale-vaccinated cattle. The RLB and the nested PCR procedures showed bacteremia with sensitivity of 50 infected erythrocytes per milliliter. Up to 93% of the A. centrale vaccinates carried specific antibodies that were detected by cELISA, and up to 71% of the vaccinated cattle were found to be naturally infected with A. marginale according to the PCR and the RLB assays. Nevertheless, no severe outbreaks of A. marginale infection occurred among vaccinated herds in this endemic region. It appears that both, molecular tools and serology are useful for evaluation of the vaccine efficacy. In the light of wide natural field infection with A. marginale, strong recommendations to continue the A. centrale vaccination program regime will continue until a new generation of non-blood-based vaccine will be developed. 相似文献
4.
Mtshali MS de la Fuente J Ruybal P Kocan KM Vicente J Mbati PA Shkap V Blouin EF Mohale NE Moloi TP Spickett AM Latif AA 《Zoonoses and public health》2007,54(1):23-30
Bovine anaplasmosis, caused by the tick-borne rickettsia Anaplasma marginale, is endemic in South Africa and results in considerable economic loss to the cattle industry. This study was designed to characterize strains of A. marginale at the molecular level from cattle raised in communal and commercial farms in the north-eastern and south-western regions of the Free State Province, South Africa, that varied in rainfall and vegetation. Seroprevalence to A. marginale was determined in 755 cattle by an Anaplasma spp. competitive enzyme-linked immunosorbent assay and ranged from 44% to 98% and was similar in both regions. While Anaplasma centrale was not targeted in this study, A. marginale infections were identified by species-specific msp1alpha polymerase chain reaction in 129 of 215 of the samples studied. Similar genetic diversity of A. marginale strains was found in both the north-eastern and south-western regions. The sequences of 29 A. marginalemsp1alpha amplicons from South African strains revealed considerable genetic diversity providing 14 new repeat sequences. However, 42% of MSP1a repeat sequences were not unique to this region. These results indicated the presence of common genotypes between South African, American and European strains of A. marginale. Cattle movement between different parts of South Africa was suggested by the presence of identical A. marginale MSP1a genotypes in north-eastern and south-western regions of the Free State Province. Control strategies for anaplasmosis in South Africa should therefore be designed to be protective against genetically heterogeneous strains of A. marginale. 相似文献
5.
Varda Shkap Hanna Ungar-Waron E. Pipano C. Greenblatt 《Tropical animal health and production》1984,16(4):233-238
The use of the ELISA method for the detection of antibodies to B. besnoiti in cattle is described and compared to the IFAT technique. One hundred and twenty-one sera were examined, of which 61 were sera of calves experimentally infected with B. besnoiti, 52 sera from field animals and eight were sera with high titres of antibodies to other parasites. The specificity of both assays correlates but ELISA seemed to be more sensitive. The ELISA technique provides a rapid and reliable method for the screening of B. besnoiti infection in cattle. 相似文献
6.
V Shkap H Ungar-Waron E Pipano C Greenblatt 《Veterinary immunology and immunopathology》1985,9(1):53-57
Specific precipitable antibodies of both IgG and IgM classes were detected in sera of cattle naturally infected with B. besnoiti. The amount of specific antibodies of the IgG class precipitated by soluble antigen was in the range of 17-50 micrograms/ml serum while that of the IgM class ranged between 5 and 24 micrograms/ml serum. Specific antibodies precipitated by live B. besnoiti parasites were in amounts of 10 to 22 micrograms/ml serum for IgG and 4 to 26 micrograms/ml serum for IgM. Different ratios of IgG/IgM were obtained by the two methods of precipitation. This might indicate that antibodies to B. besnoiti of the IgM class can be precipitated and detected in sera of naturally infected cattle in similar amounts either by live parasites or by solubilized antigen, whereas antibodies of the IgG class can be preferentially detected when solubilized antigen is used for precipitation. 相似文献
7.
Neospora caninum is a coccidian parasite identified as a major cause of abortion in cattle. A combined infection of N. caninum with another taxonomically related parasite of cattle, Besnoitia besnoiti can occur in geographical areas endemic for both species. Both infections are routinely diagnosed serologically, and incorrect diagnosis could occur if immunological cross-reactivity exists between the two parasites. To investigate the possible degree of cross-reactivity, we compared results obtained with two serological techniques, immunofluorescent antibody test (IFA), and Western blot analysis on known positive and negative sera. The test sera were derived from naturally infected cattle and from experimentally infected Mongolian gerbils. In IFA of bovine sera, no cross-reactvity was detected at the commonly used serum dilution cutoffs of 1:200 for N. caninum and 1:256 for B. besnoiti. However, at 1:64 dilution of both cattle and gerbil sera, anti-N. caninum sera reacted with B. besnoiti antigen in some individual samples. Anti-B. besnoiti serum did not react with N. caninum antigen at any dilution. This low level one directional cross-reactivity was confirmed by Western blot analysis. B. besnoiti antigen showed two immunoreactive bands when probed with anti-N. caninum serum, while no bands appeared when N. caninum antigen was probed with B. besnoiti antiserum. Immunization and challenge experiments in the highly susceptible Mongolian gerbil (Meriones unguiculatus) showed essentially no cross-protection between N. caninum and B. besnoiti. 相似文献
8.
Shkap V Leibovitz B Krigel Y Molad T Fish L Mazuz M Fleiderovitz L Savitsky I 《Veterinary microbiology》2008,130(3-4):277-284
Bovine anaplasmosis, caused by Anaplasma marginale, the intraerythrocytic rickettsia, is controlled by vaccination with live Anaplasma marginale ss centrale (A. centrale), a subspecies of relatively low pathogenicity. We have experimentally demonstrated that an animal primarily infected with A. marginale, or with the related vaccine subspecies A. centrale can be infected with the heterologous subspecies, and carries both bacteria. The co-infection was detected in experimentally cross-infected calves for up to 3 months after the last inoculation with the heterologous subspecies. The occurrence of characteristic cyclic rickettsemia of A. centrale and A. marginale was observed by examination of Giemsa-stained blood smears, or by the presence of specific rickettsial DNA confirmed in PCR assays based on specific msp1a and msp4 for A. marginale, and on specifically designed msp3 and msp4 primers for A. centrale. Sequence analysis of msp4-specific fragments for each subspecies revealed the presence of dual infection in both calves on days 30 and 60 after cross-inoculation with the heterologous Anaplasma subspecies. The experimental cross-infection of calves clearly demonstrated that the concept of "infection exclusion" does not apply to Anaplasma infection in cattle; as there was no infection exclusion of A. marginale in A. centrale-infected cattle, and vice versa. The present results confirmed our previous findings that cattle grazing in an anaplasmosis-endemic field were subject to concomitant infection with both the vaccine A. centrale and the field A. marginale strains. 相似文献
9.
Experimental parameters for optimization of the growth conditions of Besnoitia besnoiti endozoites in vitro are presented. A combination of Hepes-buffered McCoy and Leibovitz (ML) medium with 10% bovine serum was preferable to Eagle's Minimum Essential Medium (MEM) based on either Hank's or Earle's salts. The ML medium and a CO2 balanced gas phase significantly increased the growth rate of the parasite. Infection of Vero cells at 1 h after subcultivation resulted in higher yields of endozoites than infection of 24- or 48-h-old cells. Increased numbers of parasites (6 x 10(7) and 9 x 10(7)) in the infection inoculum per Roux bottle containing Vero cells produced poor yields, while infection with 2 x 10(7) parasites resulted in a 250 to 300-fold increase after 6 days of cultivation with one medium change. 相似文献
10.
V Shkap H Ungar-Waron E Pipano 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1990,43(1):63-68
Soluble antigens from culture-grown Besnoitia besnoiti endozoites were identified following their partial purification by affinity chromatography. A specific eluate obtained after affinity chromatography on a column to which antibodies from serum of a naturally infected cow were bound exhibited seven polypeptide bands on sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). Five bands were observed in the eluate from an immunoadsorbent to which antibodies from an experimentally infected calf were coupled. Eluted antigens were reactive in the enzyme-linked immunosorbent assay (ELISA). Reactivity of electrophoretically resolved antigens with sera of endozoite-inoculated cattle and sera from field cases of besnoitiosis were studied using the Western immunoblotting technique. 相似文献