Journal of Life Science (생명과학회지)

Korean Society of Life Science (한국생명과학회)
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Classifying Host Susceptibility Using Porcine Circovirus Type 2 Viral Load and Antibody Titer

돼지 써코바이러스 2형 감염량과 항체가를 이용한 자돈의 저항성군 선발법

  • Lim, Kyu-Sang (College of Life Sciences and Biotechnology, Korea University) ;
  • Lee, Eun-A (College of Life Sciences and Biotechnology, Korea University) ;
  • Lee, Kyung-Tai (Division of Animal Genomics and Bioinformatics, National Institute of Animal Science, RDA) ;
  • Chun, Taehoon (College of Life Sciences and Biotechnology, Korea University) ;
  • Hong, Ki-Chang (College of Life Sciences and Biotechnology, Korea University) ;
  • Kim, Jun-Mo (Division of Animal Genomics and Bioinformatics, National Institute of Animal Science, RDA)
  • 임규상 (고려대학교 생명과학대학 생명공학부) ;
  • 이은아 (고려대학교 생명과학대학 생명공학부) ;
  • 이경태 (농촌진흥청 국립축산과학원 동물유전체과) ;
  • 전태훈 (고려대학교 생명과학대학 생명공학부) ;
  • 홍기창 (고려대학교 생명과학대학 생명공학부) ;
  • 김준모 (농촌진흥청 국립축산과학원 동물유전체과)
  • Received : 2016.11.08
  • Accepted : 2016.12.26
  • Published : 2017.03.30
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Abstract

Porcine circovirus type 2 (PCV2) is a notorious and ubiquitous virus in the swine industry. The susceptibility of the host to PCV2 infection is considered to be one factor associated with the dynamics of PCV2. The objective of this study was to verify the criteria for host susceptibility to PCV2, using blood parameters of post-weaned pigs naturally infected with the virus. The PCV2 DNA viral load, antibody titer, and leukopenia characteristics were measured in the serum extracted from the pigs at the 10th week. We classified the pigs into high (>5.0), intermediate (3.0 to 5.0), and low (<3.0) groups on the basis of the PCV2 viral load (log copies/ml), or as positive (${\leq}0.50$) and negative (>0.50) groups on the basis of antibody titer (sample-to-negative corrected ratio). Moreover, using these two categorized parameters, we suggested the criteria for classification into the susceptible and resistant groups. Statistical analyses revealed that pigs in the susceptible group had a significantly higher viral load (p<0.001) and negative antibody titer (p<0.001), as well as significantly lower leukocyte counts (p=0.018) and lower amounts of several leukocyte components (p<0.05), than pigs in the resistant group. We concluded that the susceptible group could be considered to have PCV2-induced leukopenia. Therefore, we suggest that the combined classifications of viral loads and anti-PCV2 antibodies can be used to determine PCV2-induced leukopenia in the subclinical PCV2 infection of post-weaned pig populations.

양돈산업에 있어 돼지 써코바이러스 2형(PCV2)의 복합감염으로 인한 이유자돈의 질병 피해가 막대하다. PCV2 감염에 대한 숙주의 민감도는 상이한 것으로 알려져 있으며, 따라서 숙주의 민감도를 구분하는 것은, 이를 이용한 숙주의 저항성 향상 연구에 필수이다. 본 연구의 목적은 이유자돈군의 혈액 내에서 PCV2 바이러스에 대한 숙주의 민감도를 구분 짓고 구명하는데 있었다. 본 연구에서는 자연적으로 바이러스에 감염된 10주령의 이유자돈군으로부터 혈청을 채취하여 PCV2 바이러스량과 항체가를 측정하고 혈구분석을 실시했다. 또한, 측정된 PCV2 바이러스량과 항체가를 기준으로 자돈군 내에서 저항성군과 민감성군을 선정하였고, 통계분석결과 저항성군에 비해 민감성군에서 백혈구 수가 현저히 줄어든 것을 확인하였다. 본 연구를 통해서 PCV2 감염에 대한 돼지의 민감도를 구분짓기 위한 PCV2 바이러스량과 항체가를 이용한 복합기준을 제시할 수 있었으며, 이유자돈군의 PCV2 관련 질병저항성 및 백혈구감소증을 확인할 수 있는 방법을 마련하였다.

Keywords

References

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