Theileria buffeli infections in grazing cattle in the Republic of Korea
- Author:
Han, Y.J.
;
Han, D.G.
;
Choi, K.S.
- Publication Type:Journal Article
- From:Tropical Biomedicine
2017;34(2):263-269
- CountryMalaysia
- Language:English
-
Abstract:
Theileria infections are encountered worldwide, occasionally resulting in serious
economic losses for the livestock industry. This study is an epidemiological survey of Theileria
infections in Korean indigenous cattle populations in the Republic of Korea (ROK). Blood
samples were collected from 100 cattle in April (n=50) (prior to pastureland grazing), and
again four months later, in August (n=50) (half of the cattle put out for grazing and the other
half kept in housing). All samples were tested for the presence of Theileria infection based on
PCR amplification of the small subunit of ribosomal RNA gene. Twenty-two samples across
the whole study were verified as positive for Theileria infection by PCR methods. In August,
Theileria infection was markedly increased in grazing cattle (16/25 animals, 64%) compared
with indoor cattle (4/25 animals, 16%); affected animals exhibited no clinical signs of infection.
The red blood cell, hematocrit, and hemoglobin values were significantly lower in Theileria-
positive cattle than in Theileria-negative cattle. Phylogenetic analysis demonstrated that
the isolates from this study belonged to the T. buffeli species, and were significantly related
to Types A, B, C, and E, and were distinct from T. buffeli Type D, which is known to be more
pathogenic. These findings indicate that T. buffeli identified in Korean indigenous cattle have
a low-to-mild pathogenicity. These results suggest that the T. buffeli infection is relatively
higher in the ROK, and the infection rate may increase following grazing. Taken together, T.
buffeli infection may not only be seasonally correlated, but also may be affected by
management practices such as pastureland grazing.
- Full text:P020170616360396427533.pdf
