A Bordetella bronchiseptica strain isolated in Taiwan was grown on Bordet-gengouagar Then the colonies of pharacteristics were selected and transferred intoTrvptic soy broth for preliminary culture. For preparation of large quantity of atrophic rhinitis (AR) diagnostic antigen, the isolate was grown on potato infusion agar at 37? for 24 hours. The grown colonies were washed with phosphate buffered saline, them filtrated and washed again, then adjusted to 5x 10-il CR7 ml (approximately 6-7° o transmittance 620nm at 10-1 dilution). The suspension was inactivated with 0.2% formalin and added 0.02% thimerosal was added as a preservative in the final concentration. Two Summa lots of the AR diagnostic antigens were prepared and then checked with plate and tube agglutination methods with rabbit immune sera and swine sera collected from the field. The results showed that both of antigens had very high accuracy and quite stable sensitivity.
It the field application test, swine sera collected from two different farms were examined for AR infection. The positive reaction of AR in farm A and B were 6 out of 10 as well as 14 out of 27 specimens, respectively.
The highest serum titer, 1:160, was ever examined from these locations. It means that the AR infection is considerably high in Taiwan
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