Prevalence and risk factors of tropical theileriosis, and sequencing of Theileria annulata, the causative pathogen, in Setif region (Algeria) before and after tick season

Abstract

To determine the prevalence of Theileria annulata infection and the influence of some risk factors, a molecular survey was carried out in the Setif region (Alge­ria). A total of 134 cattle blood samples from 21 farms were collected twice, in April and November 2015, before and after the tick vector season. Theileria annulata molecular prevalence was 25.4% in April and and 50% in November, indicating a significant increase (p < 0.001) in the number of asymptomatic car­rier animals. The molecular prevalence was significantly higher than the preva­lence in Giemsa-stained blood smears for the two periods. In April, the Fleck­vieh breed had the lowest molecular prevalence, but this prevalence increased significantly in November (p < 0.001). The breeding type and sex had no influ­ence on T. annulata prevalence. However, the infection rate increased signifi­cantly during the tick infestation period as the walls were not roughcast and had cracks (p < 0.001). The Algerian Tams1 gene sequence was very similar to the already known Mauritanian, Tunisian and Egyptian sequences.