Abstract
Tropical theileriosis is a serious animal disease transmitted by tick vectors. The agents of theileriosis are obligate intracellular parasites that cause mild to severe disease in the mammalian host. Tropical theileriosis has been recognized as a burden to the development of the dairy industry in Sudan and causes major economic losses. However, knowledge about the distribution of
Theileria
spp
.
in Sudan and the extent of sequence variation within the 18S rRNA gene is currently unknown. The aim of this study was to determine the diversity of
Theileria
spp. using 18S rRNA-based PCR to detect parasites in cattle followed by cloning and sequencing. We observed an overall prevalence rate of 63% hemoparasite infection in cattle from Sennar state. A subset of samples was used for cloning and sequencing of the 18S rRNA gene. Nineteen of 44 animals were co-infected with more than one species of
Theilera
. Phylogenetic analysis revealed three
Theileria
spp. that were predominant in cattle including pathogenic
T. annulata
and apathogenic
T. velifera
and
T. mutans
. The present study provides information regarding the prevalence of theileriosis in Sudan and will help to design strategies to control it. Additionally, more study is needed to determine tick vector competence and degree of coinfection with multiple
Theileria
spp. in Sudan. This represents the first molecular phylogeny report to identify
Theileria
spp. in cattle from Sudan.