Evaluation of New and Currently Used Diagnostic Procedures for Bovine Brucellosis

A radial immunodiffusion (RID) test employing a polysaccharide antigen (poly B) was compared with tests currently used in the diagnosis of bovine brucellosis. Over 1,000 sera from vaccinated and infected cattle, all of which had been examined bacteriologically, were used to determine the sensitivity and specificity of the RID, card, Rivanol, and complement fixation tests. The RID test identified 90% of the cattle that were shedding Brucella in their milk. Although the complement fixation test was more sensitive, it was less specific than the RID test in cattle vaccinated as adults with Brucella abortus strain 19. A sensitive screening test, such as the card test, in combination with the RID test could be used in diagnostic laboratories, or even in the field, with little additional expense or technical expertise. An additional advantage is that the RID could be applied to sera from adult cattle as early as 2 months after vaccination, when postvaccinal agglutinins and complement-fixing antibodies may still be present. The indirect hemolytic test was used with some of the sera and was found to be a very sensitive test which could be useful in areas of low incidence but would not be practical for large-scale testing in adult-vaccinated herds.

Section: Discussionmentioning

confidence: 99%

Evaluation of a radial immunodiffusion test with polysaccharide B antigen for diagnosis of bovine brucellosis

Jones¹,

Berman²,

Moreno³

et al. 1980

“…The cattle were mated at 14 to 16 months of age, and approximately 3 months after mating, they were examined rectally for pregnancy. At this time, the 46 pregnant animals were challenged via the conjunctival route with 15 x 106 viable B. abortus strain 544 (S544) organisms (8), and 14 nonpregnant animals received 15 x 107 viable S544 organisms (6,14).…”

Section: Methodsmentioning

confidence: 99%

Comparison of the complement fixation test and the indirect hemolysis test for cattle vaccinated and infected with Brucella abortus

Sutherland¹,

Cras²,

Evans³

1982

The complement fixation test (CFT) and indirect hemolysis test (IHLT) were applied to sera collected from 60 cattle challenged with Brucella abortus 544. Of the 60 cattle, 48 were vaccinated with either B. abortus 19 or B. abortus 45/20 as calves or as adults. The remaining 12 cattle were not vaccinated. Of the 27 sera from cattle found to be infected, 9 showed aberrant reactions to the CFT. The advantages of the IHLT for these cattle were as follows. After challenge, the titers to the IHLT became positive earlier than or at the same time as the titers to the CFT, they persisted longer than the titers to the CFT, and they failed to show prozone reactions, which are a problem with the CFT. An additional advantage was that before challenge and after vaccination with strain 19, the titers to the IHLT rose later and declined earlier than the titers to the CFT. We concluded that the CFT used in conjunction with the IHLT improves the detection of infected cattle.

“…This test measures the ability of antibodies and complement to lyse bovine erythrocytes (BRBC) which have been coated with Brucella abortus antigens. Evaluation of the IHLT showed that it is effective in diagnosis (29,33), and test parameters were evaluated by Hoffmann et al (15).…”

mentioning

confidence: 99%

Immunoradiometric assay for examination and quantitation of Brucella abortus-specific antibodies reactive with the antigen(s) used in the indirect hemolysis test

Tedder¹,

Hoffmann²

1981