Comparative study of the serum antibody levels in sheep nasal carriers of Pasteurella haemolytica

Abstract

The population of P. haemolytica in the nasopharynx was examined in a group of 13 housed sheep, of mixed sex and breed, using the indirect haemagglutination test to identify the serotypes. The sheep were bled at fortnightly intervals over a 6-month period and the sera was tested for the presence of antibodies to serotypes A1, A2, A6, A7, A9, T3 and T10 using both the Indirect Fluorescent Antibody and Indirect Haemagglutination tests.

Five serotypes of P. haemolytica were isolated and comparisons of the 2 serological tests showed statistically that the F. A. test was more sensitive than the I. H. A. test, but possibly less specific.