| prevalence of antibodies to infectious bursal disease virus serotypes i and ii in 75 ohio chicken flocks. | serum samples from 75 ohio layer flocks were tested for antibodies to infectious bursal disease virus (ibdv) serotypes i and ii using a virus-neutralization test. infectious bursal disease had been diagnosed in three of the 75 flocks. antibody titers to serotype i were detected in 77% of the flocks, and antibody titers to serotype ii were detected in 47% of the flocks. of the eight flocks known to have been vaccinated using a serotype i ibdv vaccine, all had antibody titers to serotype i, and fo ... | 1983 | 6314983 |