Epidemiological survey of Theileria orientalis infection in grazing cattle in the eastern part of Hokkaido, Japan.
Theileria orientalis is one of the benign species of Theileria that is widely distributed in Japan and is sometimes responsible for serious economic losses in the livestock industry. In the present study, we surveyed the current status of T. orientalis infection in grazing cattle in the eastern areas of Hokkaido (Taiki, Otofuke, Shintoku, and Shin-Hidaka districts) using molecular methods, as well as traditional methods, of diagnosis. The genes encoding the major piroplasm surface protein (MPSP) and p23 of T. orientalis were identified using highly detectable polymerase chain reaction (PCR). Results of the MPSP-PCR assay indicated that grazing cattle in these districts, after about 1.5 months pasturage, showed high rates of infection, ranging from 10.0-64.8%. Although the main MPSP and p23 genotypes detected were the Ikeda- or Chitose-types, an MPSP gene closely relating to that found in Okinawa prefecture, and a p23 gene closely relating to the Australian (Warwick) Buffeli-type gene, were found in the cattle in Shintoku and Shin-Hidaka districts. The present survey indicated that there were at least five types of T. orientalis classified by their MPSP genes in Hokkaido, Japan, and that T. orientalis infection rates are still high in this region.
Ota
Naomi
N
Obihiro University of Agriculture and Veterinary Medicine, Hokkaido, Japan.
Mizuno
Daisuke
D
Kuboki
Noritaka
N
Igarashi
Ikuo
I
Nakamura
Yukio
Y
Yamashina
Hidenari
H
Hanzaike
Teruko
T
Fujii
Kei
K
Onoe
Sadao
S
Hata
Hiroshi
H
Kondo
Seiji
S
Matsui
Shirou
S
Koga
Masao
M
Matsumoto
Kotaro
K
Inokuma
Hisashi
H
Yokoyama
Naoaki
N
D000818:Animals; D002417:Cattle; D017125:Genes, Protozoan; D007564:Japan / Q000453:epidemiology; D017720:Molecular Epidemiology; D018512:Parasitemia; D010802:Phylogeny; D011159:Population Surveillance; D016794:Theileria / Q000235:genetics / Q000302:isolation & purification*; D013801:Theileriasis / Q000453:epidemiology* / Q000469:parasitology