Characterization of Bovine Parainfluenza Virus Type 3

Abstract
Bovine parainfluenza virus type 3 (PIV‐3) has a buoyant density of 1.197. The RNA of PIV‐3, like that of Sendai virus, is a single continuous chain which lacks polyadenylic acid sequences and tends to self‐anneal to a marked extent. It has a sedimentation coefficient of 42S and a molecular weight of 4.5 × 106, being slightly smaller than Sendai virus RNA (47S, 5.3 × 106).