Evaluation of the cold complement fixation test for diagnosis of ovine brucellosis

SUMMARY A cold complement fixation test for ovine brucellosis in which fixation of complement occurs for 16 h at 4°C was compared with the conventional warm complement fixation test in which fixation takes place for 40 minutes at 37°C. The cold complement fixation test detected experimentally infected animals up to one week sooner than the warm complement fixation test and the titres were approximately one twofold dilution higher. Similar results were obtained when the 2 tests were compared using 11,922 serum samples collected from 700 ram flocks over a 2-year period. False positive reactions were observed in less than 0.1% of cases.     

动物布鲁菌病补体结合试验诊断方法比较研究

布鲁菌病是造成严重公共卫生安全和经济损失的人畜共患病,目前对该病的血清学诊断方法主要有凝集试验、ELISA、补体结合试验等,其中补体结合试验(CFT)是世界动物卫生组织(OIE)认可的布病血清学确诊的经典标准方法。但在实际布病检验中,由于其原理复杂、操作繁琐、影响因素多、耗时长等原因而未能被广泛应用。为了进一步明晰其原理,提高CFT的可操作性及准确性,本文比较了我国动物布鲁菌病标准和OIE手册中CFT的差异,并结合本实验室应用情况,对CFT在布鲁菌病诊断中常见的问题和注意事项进行了阐述,为布鲁菌病补体结合试验的科学应用及诊断提供了参考。     

牛布鲁菌病补体结合试验测量不确定度评估

本试验应用补体结合试验方法对牛布鲁菌病进行检测,分别从溶血素效价测定、补体效价测定、抗原效价测定及血清效价测定4个方面分析了补体结合试验测量不确定度来源,并计算了合成不确定度、扩展不确定度,最终样品测量结果报告值为:X=(1.06±0.043) mg/mL(95％置信区间),即本试验中判定的可以抑制50％溶血的血清最高效价所对应的溶血素浓度为1.06mg/mL,不确定度U为0.043.     

Effectiveness of the surface fixation test in the diagnosis of brucellosis in hares

In the course of two years the reliability of surface fixation test was tested in the diagnostics of hare brucellosis on 961 hare blood samples taken during chases at chosen localities of the Olomouc district. Out of 33 serologically positive hares, 29 reacting ones were subjected to complex laboratory examination for brucellosis. In all cases brucellosis was confirmed patho-anatomically, by cultivation in 78.95% of bacteriologically examined hares and in the rest cases by bioassay on guinea-pigs. The results have confirmed that the surface fixation test represents a highly effective method for the reliable serological diagnostics of hare brucellosis.     

The relationship between the microtitration serum agglutination and complement fixation tests in bovine brucellosis serology

The relationship between antibody titres in the microtitration serum agglutination test and the complement fixation test in bovine brucellosis is described. For low and high MSAT values there is good agreement between the 2 tests. This is not the case for MSAT values between 54 and 338 IU/ml. For practical reasons, results falling into this category cannot all be repeated. Repetitions are so structured that less than 4% of the tests need to be repeated. If the level of repetitions should show an increase above 4%, it is assumed that technical or human error has occurred.     

Value of the antiglobulin test and indirect immunofluorescence test in the serological diagnosis of bovine brucellosis]

In investigations of 5881 sera from brucella infected herds and 8635 sera from negative herds the antiglobulin test (AgT) because of its high susceptibility was shown to be a valuable method in early diagnosis of brucellosis and clearing of non-specific LA-reactions. However, all infected animals are not detected with the AgT. Therefore it is not adaptable to use in selection controlling, also in combination with other methods. In the final steps of the eradication measures against bovine brucellosis the AgT offers a very valuable serological complementary method. The indirect fluorescence test has no diagnostical advantages in comparison with the AgT and is not recommended for practical brucellosis serology.     

The complement fixation test for the diagnosis of Brucella ovis infection in rams

Complement fixation tests using three B. ovis antigen preparations in warm fixation tests (WCFT) and cold fixation (CCFT) tests were done on 541 ram sera. Semen samples from the same rams were examined culturally to identify B. ovis excretors. The CCFT, using an antigen prepared by heat extraction of B.ovis cells, had a sensitivity of 97% in 124 rams which were shedding B.ovis. The specificity was 99% in 144 rams from non-infected flocks. Seventy-seven per cent of 156 rams which reacted to this test were shedding B. ovis in their semen. Tests with other antigens were inferior in sensitivity and/or specificity. The WCFT gave lower titres than CCFT. Vaccination caused large numbers of false positive reactions in 4 flocks.