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Published on: July 11, 2015
Interference of intradermal tuberculin tests on the serodiagnosis of paratuberculosis in cattle
Renato Varges1, Carla Dray Marassi, Walter Oelemann
1Veterinary Bacteriology Laboratory, Universidade Federal Fluminense, Niterói 24210-130, Brazil.
Abstract:
In this experiment 63 animals from a paratuberculosis (PTB) and tuberculosis-free herd were tested by Intradermal Tuberculin Tests (ITT) and blood samples were collected before PPD inoculation and on days 3, 15, 30, 60 and 90 post-inoculation (p.i.). Sera were tested for PTB-specific antibodies by ELISA-PPA and confirmed by a commercial ELISA. Three (4.76%) animals were positive by ELISA-PPA and five (7.93%) in the commercial ELISA, between days 30 and 90 p.i. These results suggest that ITT can interfere in the reliability of ELISAs and that serological testing for PTB should be avoided for 90d after PPD inoculation.
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