Comparative study on serological, bacteriological, and molecular methods for diagnosis of Brucellosis in the milk of cows with reproductive disorders

Abstract

BackgroundBrucellosis is a significant animal disease communicable to humans that affects cattle worldwide. It is spreading disease in many developing countries. Brucellosis in farm animals induces serious economic costs in undeveloped countries and causes serious health hazards to dairy users. Sensitive and accurate diagnostic techniques are necessary for disease surveillance and management. FindingsIn this investigation, the overall prevalence of brucellosis in examined animals was 34.91% by MRT, while i-ELISA showed 33.96% prevalence. the sensitivity and specificity of MRT were 93.55%, and 89.33% and ELISA were 96.77%, 92 % respectively. whereas, the false positive was 10.67% and 8.00% for MRT and ELISA respectively. Brucella microorganism was isolated in 25.47 % milk samples, all Brucella strains were determined as B. melitensis biovar 3. By conventional PCR and real-time PCR, 28.3% of samples were positive. The results showed that the sensitivity of bacteriological culture, Conventional PCR, and Real-time PCR was 87.10%,96.77%, 96.77% respectively while specificity was 100% each, and estimated false positive was zero% each.ConclusionThe milk ELISA had detected high sensitivity and specificity than those of the milk ring test. B. melitensis biovar 3 is the predominant strain isolated in the milk of cows with reproductive disorders. The PCR's high sensitivity and specificity, as well as its speed, and low risk to laboratory workers, make it an extremely useful technique for brucellosis diagnosis. The possibility of contaminated raw milk and raw dairy products has surfaced, providing a serious public health threat.