Determinación de anticuerpos anti-PPD en hatos lecheros con distintas prevalencias de tuberculosis bovina en México

Abstract

ANTIBODY RESPONSE TO PPD OF CATTLE FROM HERDS WITH DIFFERENT TUBERCULOSIS STATUS WAS ASSESSED BY ELISA. TUBERCULOSIS-FREE GROUP PRESENTED SIGNIFICANTLY LOWER OPTICAL DENSITY VALUES THAN HERDS IN WHICH TUBERCULOSIS HAD BEEN CONTROLLED IN INFECTED HERDS OR CATTLE WITH NECROPSY""PROVEN TUBERCULOSIS. HIGHEST ANTIBODY LEVELS WERE FOUND IN SERUM SAMPLES FROM TUBERCULOUS CATTLE AND INFECTED HERDS. HOWEVER, SOME ANIMALS FROM THE CONTROLLED GROUP, IN WHICH TUBERCULIN REACTORS WERE NOT DEMONSTRATED IN THE LAST YEAR, SHOWED ALSO HIGH ANTIBODY LEVELS BY ELISA SUGGESTING A RESIDUAL INFECTION PRESENT IN THESE HERDS. TWO TUBERCULOUS ANIMALS, TUBERCULIN NON-REACTORS (ANERGIC), SHOWED HIGH ANTIBODY TITERS. THESE RESULTS INDICATE THE USEFULNESS OF ELISA WITH PPD AS AN ANTIGEN TO IDENTIFY ANERGIC MYCOBACTERIUM BOVIS INFECTED ANIMALS, AND FOR MONITORING AND CONFIRMING THE EPIDEMIOLOGICAL STATUS OF HERDS UNDER-CONTROL BY THE TUBERCULOSIS ERADICATION CAMPAIGN.