A comparison of titers of anti-Brucella antibodies of naturally infected and healthy vaccinated cattle by standard tube agglutination test, microtiter plate agglutination test, indirect hemagglutination assay, and indirect enzyme-linked immunosorbent assay

Abstract

Aim:We determined the antibody response in cattle naturally infected with brucellosis and normal healthy adult cattle vaccinated during calf hood with strain 19.Materials and Methods:The antibody titers were measured by standard tube agglutination test (STAT), microtiter plate agglutination test (MAT), indirect hemagglutination assay (IHA), and indirect enzyme-linked immunosorbent assay (iELISA) as per standard protocols.Results:The mean STAT titers were 1.963±0.345 in infected cattle and 1.200±0.155 in healthy vaccinated cattle. The difference was extremely significant (p<0.0001). The mean MAT titers were 2.244±0.727 in infected cattle and 1.200±0.155 in healthy vaccinated cattle. The difference was very significant (p<0.005). The mean IHA titers in infected cattle were 2.284±0.574, and those in healthy vaccinated cattle were 1.200±0.155. The difference was extremely significant (p=0.0002). However, the difference in mean iELISA titers of infected cattle (1.3678±0.014) and healthy vaccinated cattle (1.367±0.014) was non-significant. The infected animals showed very high titers of agglutinating antibodies compared to the vaccinated animals. However, it cannot be ascertained whether these antibodies are due to vaccine or response to infection. Since the infected animals had been vaccinated earlier, the current infection may suggest that vaccination was unable to induce protective levels of antibody. The heightened antibody response after infection may also indicate a secondary immune response to the antigens common to the vaccine strain and wild Brucella organisms.Conclusion:The brucellosis infected animals showed very high titers of agglutinating antibodies compared to the vaccinated animals.

Immune response of cattle to vaccination with Brucella abortus strain 19 in India

“…RBT showed no antibody found before vaccination, as no agglutination was observed. Vaccinated calves showed positive RBT, similar to the results of other workers (Afzal et al, 2000;Mohan et al, 2016;Poesteret al, 1998).…”

“…The disease also infects humans. About 50,000 cases of human brucellosis are reported every year globally (Mohan et al, 2016).…”

A Comparison of Antibody Titers in Brucellosis Affected Vaccinated Cattle, Unvaccinated Infected Cattle and Healthy Vaccinated Cattle by Agglutination Assays

“…It has been reported earlier (Mohan et al, 2016) that infected animals have very high titers of antibodies compared to the vaccinated animals. However, in the absence of an assay for differentiation of infected from vaccinated animals (DIVA assay), it is not possible to determine whether these antibodies are protective or not and are induced by the vaccine or due to response of the animal to acute infection and whether they are of any relevance to prognosis.…”

Bovine brucellosis – a comprehensive review

“…Wang et al ( 2015 ) developed a highly advanced version of a monoclonal antibody-based cELISA against LPS for the diagnosis of bovine brucellosis, which revealed higher specificity than the commercially available cELISAs and RBPT (Ahmed et al 2011 ; Kirit et al 2017 ). The analysis of the anti- Brucella antibody titers of naturally infected and vaccinated cattle by indirect ELISA, SAT, indirect hemagglutination assay and microtiter plate agglutination test revealed that the naturally infected animals presented much higher titers of agglutinating antibodies in comparison to the healthy vaccinated cattle (Mohan et al 2016 ).…”