Serological survey of Babesia bovis and Anaplasma marginale in cattle in Tete Province, Mozambique

Abstract

A serological survey of bovine babesiosis and anaplasmosis in communal cattle was conducted in the northwestern province of Tete, Mozambique. Blood was collected from cattle ranging from 4 to 15 months old from randomly selected farms from six districts. Thirty-nine per cent of all 478 calves tested in Tete Province were seropositive to the ELISA forBabesia bovis antibodies and 63% of all calves were seropositive in the card agglutination test forAnaplasma marginale. Seroprevalence ofB. bovis ranged from 22.8% in Tete City District to 48.1% in Angonia District. ForA. marginale, it ranged from 34.4% in Angonia District to 87.3% in Moatize District. The dominant factor affecting seroprevalence for both haemoparasites was district and there was a trend for higher intensity of tick control to be associated with a higher seroprevalence ofB. bovis and a lower seroprevalence ofA. marginale. The obvious differences were the low prevalence ofB. bovis in Tete City Council District and the low prevalence ofA. marginale in Angonia District. The levels of exposure toB. bovis seen in our study are well below any that could be considered to be consistent with endemic stability, yet they are sufficiently high to ensure that clinical disease would be a risk. The seroprevalence ofA. marginale, however, suggests that endemic stability with respect to this disease could exist in districts other than Angonia. There was no strong and consistent relationship between the intensity of control and the likelihood of seropositivity to either of the diseases.