Dynamics of Moraxella bovis infection and humoral immune response to Bovine Herpes Virus Type 1 during an Infectious Bovine Keratoconjunctivitis Natural outbreak in beef calves

ZBRUN, M. V.; ZIELINSKI, GUSTAVO C.; PISCITELLI, HERNÁN C.; DESCARGA, CARLOS; URBANI, LILIANA A.

JOURNAL OF VETERINARY SCIENCE

KOREAN SOC VETERINARY SCIENCE

Año: 2011 p. 347 - 352

1229-845X

Infectious Bovine Keratoconjunctivitis (IBK) is an acute infectious disease caused by Moraxella bovis (Mb). Several factors may predispose to an outbreak; however, one that is commonly associated with IBK is infection with Bovine Herpesvirus Type 1 (BVH-1). The aim of this study was to investigate the dynamics of BVH-1 virus infection and its relation to clinical cases of IBK in weaned calves from a beef herd with high prevalence of lesions caused by Mb. The sampling was carried out in 6 stages; samples taken were conjunctival swabs for isolation of Mb, blood samples for determination of antibodies specific to BVH-1 and a score for IBK lesions after observation of each eye was obtained. The findings of this study showed a high prevalence of BVH-1 virus infection (100% of animals were infected at the end of the trial), 67% of animals were culture positive to Mb but low rates of clinical IBK (19% of calves affected) was detected at the end of the trial. These results could suggest that infection with BVH-1 did not predispose these animals to clinical IBK and that Mb infection produced clinical and subclinical disease as well, in absence of BHV-1 co infection.