The effect of some physical and serological treatments on haemofusing activity of bovine parainfluenza virus type 3.
Bovine parainfluenza virus type 3 irrespective of the time of its harvesting from Madin-Darby bovine kidney cells, expressed little or no haemofusing activity. Treatment of the virus by freezing and thawing, sonication or antibody and complement enhanced this activity. Moreover haemofusing activity did not correlate with the viral capacity for fusion of susceptible cells in monolayer cultures.