Investigation of Theileria spp. in Livestock in Northern Algeria and Identification of a Novel Haplotype of Theileria orientalis

Abstract

Purpose

Theileria species are tick-borne, intracellular apicomplexan protozoan parasites that pose a significant threat to livestock health and productivity. Theileria orientalis, the etiological agent of oriental theileriosis, is a benign Theileria species with worldwide distribution, including Algeria, where investigations on its prevalence and genetic diversity in domestic ruminants are limited. This study aimed to investigate the molecular and phylogenetic profiles of Theileria spp. in Algeria.

Methods

A total of 149 blood samples were collected from cattle, sheep, and goats in Bouira and Tizi-Ouzou regions. Molecular identification was performed using a PCR assay targeting the Cox3 and Tams1 genes. Positive samples were sequenced to assess their phylogenetic relationships.

Results

Analysis of the Cox3 gene revealed an overall infection rate of 12.75% ± 2.73% (19/149), with all positive cases detected in cattle. Further analysis of the Tams1 gene identified Theileria annulata in 11.40% ± 5.10% (17/149) of the samples. Sequencing of two samples negative for T. annulata showed a 99.84% identity with Theileria orientalis.

Conclusions

This study reports the identification of a novel T. orientalis Cox3 haplotype in Algeria, emphasizing the need for further epidemiologic and phylogenetic analyses to understand better the distribution, diversity, and impact of this pathogen on livestock populations in the region.