PARALLEL INVESTIGATIONS OF DIFFERENT SEROLOGICAL METHODS FOR DETECTING SPECIFIC ANTIBODIES AGAINST BORDETELLA-BRONCHISEPTICA IN EXPERIMENTALLY INFECTED PIGLETS

The agglutination reaction is the method used most often for detecting specific antibodies against B. bronchiseptica. Not many literature da ta are available on the application of other serological methods. The aim of our investigation was to study the possibility of applying the methods of CF-Kolmer, mCF, heminhibition (HI) and agar-gel precipitati on (AGP) and to compare the results obtained with the method of microa gglutination (MA), which is used as the standard method for detecting specific antibodies against B. bronchiseptica. Blood serum was obtaine d from experimentally infected piglets as well as from piglets in co-h abitation. Blood samples were taken at fifteen-day-intervals until day 165 of the infection. The appropriate antigens were prepared from the virulent strain V of B. bronchiseptica, which was also used for exper imental infection. Using the MA method positive results were obtained for 97,3% of the investigated sera. The agglutinin level increased aft er infection and reached maximal values on day 45 (GMT = 163, 14), aft er which it decreased gradually and on day 165 it was GMT=22,63. Using the mCF method, antibodies against B. bronchiseptica were found in 81 ,1% of the investigated piglets as well as higher titers compared to t he standard CF-Colmer method. Using the HI method, positive results we re obtained for 69,4% of the piglets. The values of antibody titers ra nged from 1:4 to 1:64. The AGP method as applied, proved to be insuffi ciently sensitive. Positive results were obtained for 30.6% of the inv estigated animals.