TABLE 4.
Seroconversion detection
| Method | No. of seropositive animals detected by indicated method on indicated dpi/total no. of animalsa
|
|||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Vaccinated animals
|
Animals inoculated with indicated PRRSV isolate
|
|||||||||||||||
| 10
|
13
|
17
|
24
|
|||||||||||||
| 7 | 14 | 21 | 28 | 1-4-4 | VR-2385 | 1-8-4 | 1-4-4 | VR-2385 | 1-8-4 | 1-4-4 | VR-2385 | 1-8-4 | 1-4-4 | VR-2385 | 1-8-4 | |
| bELISA | 0/30 | 29/30 | 29/30 | 30/30 | 0/10 | 0/9 | 0/11 | 0/10 | 0/9 | 0/11 | 10/10 | 8/9 | 10/11 | 9/10 | 9/9 | 11/11 |
| IDEXX | 0/30 | 29/30 | 28/30 | 29/30 | 0/10 | 0/9 | 0/11 | 0/10 | 1/9 | 0/11 | 9/10 | 3/9 | 7/11 | 10/10 | 9/9 | 11/11 |
| IFA | 0/30 | 30/30 | 30/30 | 30/30 | 0/10 | 0/9 | 0/11 | 0/10 | 0/9 | 0/11 | 10/10 | 3/9 | 9/11 | 10/10 | 9/9 | 11/11 |
a
Results of seroconversion detection by bELISA, IDEXX ELISA, and IFA were compared using samples from a vaccination-inoculation study. Overall, the methods agreed well. The kappa value for the comparison of bELISA to IDEXX was 0.94. The kappa value for the comparison of IDEXX to IFA was 0.95. The kappa value for the comparison of IFA to bELISA was 0.96. There were differences at certain dpi (depending on the virus isolate examined).