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1.
The direct, the modified direct and the indirect complement-fixation tests were investigated as methods for the detection of antibodies for the enzootic pneumonia mycoplasma and for Mycoplasma hyorhinis in the serum of infected pigs and of immunized rabbits. Only the modified direct complement-fixation test in which the guinea-pig complement is supplemented with fresh, normal unheated calf serum was suitable for the detection of mycoplasma antibodies in sera of infected swine. Based on the close correlation between the production of typical lung lesions in experimentally infected pigs and the appearance of significant serum antibody titres, the modified direct complement-fixation test provides for the first time a sensitive, specific in vitro method for the detection of enzootic pneumonia in the live pig. This test also permitted the in vitro differentiation of the mycoplasma causing enzootic pneumonia from M. hyorhinis which causes polyserositis. Antibodies in the sera of rabbits were demonstrable by the ordinary direct complement-fixation test. However, in contast to the observation made with swine sera, only a slight quantitative antigenic difference between the enzootic pneumonia mycoplasma and M. hyorhinis was seen when the tests were performed with rabbit serum antibodiies. 相似文献
2.
The objective of this work was to use the ELISA technique for the serological surveillance for freedom of brucellosis of cattle, sheep and goats. By comparing 28 cattle sera taken after a brucellosis outbreak, 15 bovine sera supplied by the Federal Institute for Health Protection of Consumers and Veterinary Medicine (BgVV) and 497 serum slow agglutination test (SSAT) and complement fixation test (CFT) negative bovine sera from herds officially declared free of brucellosis, the ELISA technique not only shows higher sensitivity as compared to SSAT and CFT but also distinguishes clearly between positive and negative reactions. The serological comparison by SSAT, CFT and ELISA of 615 cattle, 624 sheep and 630 goat sera from herds acknowledged as brucellosis free showed equivalent specificities for both CFT and ELISA. The specificity of the SSAT was much lower, 81.1% in cattle and 96.2% in goat sera. The examination of 5796 cattle, 1337 calf, 5031 sheep and 1796 goat sera demonstrates the advantage of the ELISA technique as routine method. The possible application of the ELISA technique as a screening method for serological brucellosis tests in sheep, goats and possibly also in pigs is discussed. 相似文献
3.
The fluorescein-labelled antibody technique was investigated for the diagnosis of toxoplasmosis. The direct method, the inhibition and indirect modifications are suitable for the demonstration of Toxoplasma gondii in fluid and tissue-impression slides from animals in the acute phase of infection. The method was not applicable with the frozen tissue sections. The fluorescein-labelled antibody inhibition technique detected antibodies in immune sera from various species of animal. However the titres obtained were lower than with the complement-fixation test. 相似文献
4.
The complement-fixation, the serum neutralization tests and the fluorescent-antibody technique were the serological methods applied in this laboratory for the detection of antigens for bovine virus diarrhea (BVD). As observed previously, the modified direct complement-fixation (MDCF) test was required to demonstrate antibodies against virus infections of cattle. At a certain stage of infection, the MDCF test was found to be as accurate and less time-consuming than the serum neutralization test for the detection of antibodies in bovine sera. The modified direct complement-fixing antibodies were detectable in the serum from approximately three weeks up to a few months after infection as compared to several years for the serum neutralization test. Thus, as in most other viral diseases, the MDCF test was of value for detecting recent infections while the serum neutralization test detects both recent and long-standing infections. The fluorescent antibody technique was of value to detect viral antigens of both cytopathogenic and noncytopathogenic strains of BVD in primary fetal kidney cell cultures inoculated with field specimens. In addition, the virus was detected in six of 220 fetuses collected at a local slaughter house for the preparation of primary cell cultures. The length of time required for the detection and identification of specific viral antigens by immunofluorescence was considerably reduced over that of the serum neutralization and virus interference tests. 相似文献
5.
The modified direct complement-fixation test, supplemented with unheated normal calf serum, was used to demonstrate antibodies in sera of swine immunized to African swine fever virus. These antibodies did not react in the ordinary direct non-supplemented complement-fixation test. African swine fever complement-fixing antigen in infected swine tissue is not denatured by extraction with fat solvents. Consequently, good antigens devoid of non-specific reactivity were obtained by extraction with a mixture of acetone and ether. The virus was detected in infected swine tissue harvested one day after beginning of pyrexia. The modified direct complement-fixation test demonstrated cross-reactions between the six strains of virus studied. 相似文献
6.
The direct, modified direct and indirect complement-fixation tests and the fluorescence-inhibition test were investigated using sera from pigeons, chickens and turkeys which had been exposed to Toxoplasma gondii. The direct CF test was suitable for use with pigeon sera. The indirect CF method effectively demonstrated antibodies in chicken and turkey sera. FI tests were less sensitive than the CF methods. 相似文献
7.
The complement-fixation test used at Onderstepoort was compared with the method used at A.D.R.I. on infected calf and sheep sera. In the first method, the tests are incubated at 37°C for 90 minutes and the test sera are inactivated at 53°C; whereas in the A.D.R.I. method, the test sera are inactivated at 60°C for 30 minutes, incubation is at 9°C for 18 hours, and guinea-pig complement is supplemented with 5 per cent fresh, non-inactivated, normal calf serum. Serial serum samples from one of six experimentally infected calves were negative in the Onderstepoort test, three calves gave only trace reactions and two showed maximum titres of 1:10 whereas all six had maximum serum titres of 1:10 to 1:80 in the A.D.R.I. test. A good correlation was obtained, however, between the results of the two methods with the sera of experimentally inoculated sheep although titres 3 to 8 times higher were obtained with the A.D.R.I.'s test. Post inoculation bleedings from each sheep reacted in both tests. 相似文献
8.
Ten sera collected during the winter months from six sheep infected with Johne's bacilli were fractionated on Sephadex G-25 columns, and all fractions tested for complement-fixing antibody, anticomplementary properties and for supplementing and inhibitory activities when added to complement-fixation tests of a heterologous antigen-antibody system: bovine or ovine antiserum with Brucella abortus antigen. Serum from a normal sheep was similarly fractionated and examined. The complement-fixing activity with a carbohydrate fraction of Johne's bacilli was confined principally to supernatant fractions of the earlier eluates containing the greater part of the serum proteins. Some of the unheated earlier and later fractions displayed a limited degree of supplementing effect. Inhibitory activity was demonstrated by certain of the earlier and later eluates after they had been heated, particularly those of antisera with initially low complement-fixing antibody titer. 相似文献
9.
Methods are described for the preparation of complement-fixation (CF) and hemagglutination (HA) antigens from the Texas turkey ornithosis agent grown in McCoy cell culture monolayers. The particulate antigens prepared for this study were satisfactory for testing mammalian sera by direct CF tests and avian sera by indirect CF or modified direct CF tests. Comparison of titers were made on human, bovine and ovine sera using direct CF tests employing antigen prepared for this study, 6 BC yolk sac antigen, and a commercially available antigen. The HA antigen agglutinated mouse erythrocytes, but it was not of value in hemagglutination inhibition tests because of “nonspecific” inhibitors in both mammalian and avian sera. 相似文献
10.
These studies report on the production of African swine fever antiserum for use in serological tests. The first attempt to obtain antiserum was made by inoculating ASF virus - infected pig blood into the lactiferous sinus of lactating bovines. This failed to result in the development of detectable antibody, but resulted in propagation of the virus over a 14 to 21 day period. In the second attempt use was made of a tissue culture - attenuated virus to produce resistance in normal pigs. Clinical response to inoculation with the attenuated virus was limited to a one day increase of temperature. These pigs were subsequently orally exposed to virulent ASF virus and later challenged by intramuscular injection. The sera were subjected to testing by the modified direct complement-fixation test and the agar gel double-diffusion technique in order to follow the development of antibodies. Some sera were also conjugated with fluorescein isothiocyanate and used for the detection of viral antigen by the fluorescent antibody technique. It was found that inoculation with the attenuated virus brought about the development of low antibody levels in the pigs. This antibody level did not increase following oral exposure. One pig following intramuscular challenge underwent a series of ascending temperature peaks, coinciding with increased complement-fixing titres. 相似文献
11.
The specificity of enzyme-linked immunosorbent assays (ELISA) corresponds to conventional methods for detecting brucella antibodies in bovine serum. The ELISA test detected brucella antibodies early in only 12.5% of the cattle sera tested. Also, the sensitivity of ELISA was comparable to complement-fixation and Rivanol methods, but less sensitive than the standard tube agglutination method. 相似文献
12.
A technique for producing specific antibovine IgG2 antibodies is described. The method relies on the abrogation of the class-specific antibody response of guinea pigs to bovine IgG1 by intravenous injection of goat serum immediately before immunisation in the foot pads with bovine IgG2 in adjuvant. Of the 10 resulting antisera, six were judged monospecific for IgG2 by immunoelectrophoresis but, of these, two antisera gave a very faint line in gel diffusion using IgG1 as the antigen. Radial immunodiffusion studies indicated that the strength of the antisera, using IgG2 as the antigen, was similar to antisera of guinea pigs not injected with goat serum before absorption with bovine IgG1. For guinea pigs injected with goat serum, using bovine IgG1 as an immunogen did not result in the production of subclass specific antisera, rather, the specificities were similar to those of animals not receiving goat serum. This data is compared to absorption studies of goat antibovine IgG1 and IgG2 antisera. The relationships of goat and bovine IgG subclasses are discussed. 相似文献
13.
Sera of sheep and calves infected with the California type 10 and Cyprus type 3 viruses of bluetongue were tested by the regular and modified direct complement-fixation tests. To obtain satisfactory complement fixation it was necessary to use the latter test. Cross reactivity was found, therefore, the California type 10 antigen could be used in testing sera of animals infected with the Cyprus virus. 相似文献
14.
The standard procedure for the complement-fixation test adopted in 1958 by the Animal Disease Eradication Division of the U.S. Department of Agriculture for testing of anaplasmosis was compared with the routine method used in our laboratory. In general a good agreement was observed between the two methods, although some standard control sera having a low titre in the U.S.D.A. test gave a slightly higher reaction in the A.D.R.I. test, whereas the reverse was observed with certain high titre control sera. None of the differences in titre were sufficient to change the interpretation of the tests. A survey of 3090 field samples collected from southern Alberta close to United States border detected 3 serological reactions in 3 different herds. In one of these, the animal was negative when retested 3 months later. In a second animal the serum titre was still present 11 weeks later but the blood from this animal failed to transmit infection to a susceptible splenectomized calf. In the case of the third herd the animal had been disposed of at the time of retest but all other animals in this herd at the time the reacting animal was examined were still serologically negative. This survey failed to reveal the presence of anaplasmosis in the Canadian animals investigated. 相似文献
15.
Samples of blood from 27 free-roaming elk (Cervus canadensis canadensis) from the Clearwater National Forest in north central Idaho were tested by the rapid card agglutination test and complement-fixation test for the presence of antibodies against Anaplasma marginale. The serum card test and complement-fixation test gave incomplete and false-positive reactions; the plasma card test did not give any reactions. Anaplasma bodies or other blood parasites were not observed in stained smears of elk blood. Blood from 11 elk, including 2 that were serum card test-positive, did not produce clinical, hematologic, or serologic evidence of infection in 3 anaplasmosis-susceptible bovine calves. 相似文献
16.
Since Q fever is a potential risk to personnel working with small ruminants, the serologic status of sheep and goats received at a medical school animal facility for research was evaluated. A total of 104 sheep and 102 goats were subjected to blood sample-collection procedures on arrival, as well as after a 2-week quarantine period, and the sera were tested for Q fever specific antibodies by complement-fixation (CF) and microagglutination (MA) tests. The results from the 2 tests were compared and analyzed for seroconversion. On the basis of the CF test, 14 sheep and 3 goats were considered positive; these included 7 sheep and 2 goats that seroconverted during the quarantine period. In contrast, 1 sheep and 5 goats were found positive by the MA test, which also detected seroconversion of 1 sheep and 1 goat. The use of both tests for serologic surveillance of Q fever in sheep and goats increased the likelihood of detection. Management safety practices are also required to minimize the risk of disease transmission. 相似文献
17.
As shown by density gradient ultracentrifugation and column chromatography, pigs formed IgM antibodies during the first week following vaccination with Brucella abortus, strain 19. At this time their sera reacted in both plate and tube agglutination but not in complement-fixation tests. A few days later, when IgG antibodies had developed, agglutination titers were still high and some activity was recorded in hemolytic complement-fixation tests. A similar sequence was observed in pigs repeatedly inoculated with phenol-killed suspensions of B. abortus. As the proportion of IgM to IgG antibodies decreased, agglutinin titers fell in relation to complement-fixing titers. In some animals the conglutinating complement absorption test became positive earlier than the plate agglutination. 相似文献
18.
The immune response of orally infected and parenterally vaccinated (E. COLI 08:K.:H21) gnotobiotic pigs was studied by bactericidal and indirect hemagglutination test methods. The bacterial agglutination test proved to be of no value in this study. The results demonstrated that antibody was detectable within 8 days following oral infection, but the titers remained very low until after the pigs were vaccinated intravenously. The titers of the sera were markedly increased following intravenous vaccination. There was no detectable absorption of antibody from the gut of gnotobiotic pigs fed immune serum at 4 to 6 days of age and no detectable difference between the immune response of these pigs and those not fed serum. 相似文献
19.
Counterimmunoelectrophoresis (CIE) was applied in the detection of antibodies to Mycobacterium johnei in 110 sheep, 11 goat and 31 cattle sera and compared to immunodiffusion (ID) test. One per cent Noble agar, 7 ml per slide of 5 cm x 10 cm; barbitone-tris buffer, mu = 0.03, pH 8.6; a constant current of 5 mA per slide and M johnei protoplasmic antigen at 4 mg per ml were found to impart high sensitivity to CIE and give rapid results. CIE detected 97 sheep, 11 goat and 31 cattle positive sera, a total of 139, as compared to 44, 11, 28 and 83 respectively, detected by ID. Strongly positive sera could be demonstrated within 30 minutes by CIE and the test was run for only 90 minutes while earliest reactions were not observed before 18 hours and some reactions took 144 hours to develop in ID test. 相似文献
20.
Tick-borne encephalitis (TBE) in animals is not well understood yet. TBE virus (TBEV) serology in several host species could be valuable for epidemiological analyses in the field as well as for the detection of clinical cases. However, performance and suitability of the available test systems are not well assessed. Therefore, we evaluated two commercial TBEV-ELISA kits in a pilot study and compared them for their suitability in veterinary applications. For this purpose, we tested 163 field collected goat sera and evaluated the results by serum neutralization test (SNT) as "gold standard". Twenty-eight SNT positive sera (17.2%) were detected. The best suited ELISA kit was used for determination of a species-specific cutoff for horses, cattle, sheep, goats, pigs, mice, dogs, rabbits and monkeys with defined sera from animals without known or with improbable contact to TBEV. The level of non-specific ELISA results does not only differ between animal species but may also be influenced by the age of the tested animals. The number of sera which tested false positive by ELISA was higher in older than in young sheep. In order to obtain defined polyclonal sera as references, two dogs, cattle, goats, sheep, rabbits and pigs each, as well as one horse and 90 mice were immunized four times with a commercially available TBEV vaccine. In conclusion, our results demonstrated that commercial TBEV-ELISA kits are suitable for application in veterinary medicine for both, verification of clinical TBE cases and epidemiological screening. However, positive ELISA results should be verified by SNT. Only a very low number of false negative ELISA-results were found. 相似文献
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