Evaluation of enzyme-linked immunosorbent assay using milk samples as a potential screening test of bovine tuberculosis of dairy cows in Korea.
An enzyme-linked immunosorbent assay (ELISA) using bulk tank milk samples was evaluated as a screening test for bovine tuberculosis (TB), a contagious chronic disease of cattle. An ELISA with MPB70, a major antigen of Mycobacterium bovis was performed using paired sets of milk and sera samples from 33 tuberculin-positive and 43 tuberculin-negative cattle. Anti-MPB70 antibodies were detected in milk samples and there was a significant correlation between seroreactivities of milk and sera samples (R(2)=0.83). Using the tuberculin skin test as the reference test, the sensitivities of ELISA using milk and sera samples were 87.8% and 81.8%, respectively, and the specificities were 97.7% and 100%, respectively. In the screening test using bulk tank milk samples from 931 dairy herds in Whasung, Gyeonggi-do, Korea, the positive rate for anti-MPB70 antibody was 4.5% (42/931) and the tuberculin-positive rate was 2.8% (26/931). Individual milk samples (n=253) were collected from randomly selected 8 problematic and 3 negative herds (positive and negative in the screening test by MPB70 ELISA using bulk tank milk samples, respectively) and tested by MPB70 milk ELISA. In the problematic herds, positive rates were 10.5% (20/190) for anti-MPB70 antibodies in milk ELISA and 2.1% (4/190) in the tuberculin skin test. More than one dairy cows were positive by milk ELISA among the problematic herds, and all tuberculin-positive dairy cows were positive in the milk ELISA. Further, no positive cows were detected in negative herds both by milk ELISA and tuberculin skin test. These results suggest that an ELISA, using bulk tank milk samples, might be a potential efficient screening test for bovine TB of dairy cows.
Jeon
Bo-Young
BY
Department of Microbiology and Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, 120-752 Seoul, Republic of Korea.
Kim
Seung-Cheol
SC
Je
Sungmo
S
Kwak
Jeongyeon
J
Cho
Jang-Eun
JE
Woo
Jong-Tae
JT
Seo
Sangkyo
S
Shim
Hang-Sub
HS
Park
Byoung-Ok
BO
Lee
Sung-Sik
SS
Cho
Sang-Nae
SN
D000818:Animals; D002417:Cattle; D003612:Dairying; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D007074:Immunoglobulin G / Q000032:analysis / Q000097:blood; D008403:Mass Screening / Q000379:methods / Q000662:veterinary; D008892:Milk / Q000276:immunology / Q000382:microbiology*; D056910:Republic of Korea; D014374:Tuberculin Test / Q000662:veterinary; D014380:Tuberculosis, Bovine / Q000097:blood / Q000175:diagnosis* / Q000276:immunology
D007074:Immunoglobulin G