title: Dynamics of Theileria orientalis genotype population in cattle in a year-round grazing system.
abstract: Theirelia orientalis is a tick-borne haemoprotozoan parasite, and infection with this parasite is one of the most important diseases for grazing cattle. Co-infection of cattle with different genotypes of T. orientalis often occurs. In this study, we investigated the temporal dynamics of genotypes in cattle in a year-round grazing system in Japan. Genotype-specific PCR assays to determine major piroplasm surface protein (MPSP) genotypes (types 1 to 5) of T. orientalis were performed by using time-course blood samples collected from grazing cattle and ticks in a pasture. All 20 cattle investigated in this study were infected with T. orientalis. By using genotype-specific PCR, we detected the combination of genotypes of T. orientalis (types 1 to 5) from each cattle. These multiple genotypes of T. orientalis were also confirmed in ticks. Notably, each genotype of T. orientalis in cattle was temporally detected from cattle and more variable genotypes were found in summer. The observed temporal dynamics of the MPSP genotypes of T. orientalis in cattle could be explained by host immunity against the parasites or genetic recombination of parasite in ticks.
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Masatani
authors.forename: Shunpei
authors.initials: S
authors.lastname: Yoshihara
authors.forename: Atsuko
authors.initials: A
authors.lastname: Matsubara
authors.forename: Takafumi
authors.initials: T
authors.lastname: Gotoh
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Takahashi
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Tanaka
authors.forename: Masako
authors.initials: M
authors.lastname: Andoh
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Endo
authors.forename: Tomohide
authors.initials: T
authors.lastname: Matsuo
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics; D002417:Cattle; D002418:Cattle Diseases / Q000469:parasitology*; D005828:Genetics, Population; D005838:Genotype; D007564:Japan; D016133:Polymerase Chain Reaction; D015800:Protozoan Proteins / Q000235:genetics; D012621:Seasons; D016794:Theileria / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D013801:Theileriasis / Q000469:parasitology*; D013987:Ticks / Q000469:parasitology; D013997:Time Factors
chemical_list: D000953:Antigens, Protozoan; D015800:Protozoan Proteins; C115173:major piroplasm surface protein, Theileria