Pneumonia could be experimentally induced in "Rahmany" lambs by inoculating the animals with a local isolate of parainfluenza-3 virus (PI-3).
The included lambs developed a mucoid to a mucopurulent nasal discharge on the 3rd day post inoculation (p.i.). The clinical reactions increased afterwards and were characterized by Pyrexia, coughing, sneezing and respiratory distress.
The virus was recovered from the nasal passage from the 3rd day and till the 9th day p.i. The animals examined on the 11th and 13th days p.i. were negative for virus isolation.
The HI titre appeared on the 3rd day poin, then increased progressively till the end of the experiment (13th day p.i.). In animals sacrified at different intervals, the virus could be reisolated from pneumonic areas in the lungs of 16 out of 18 lambs and also from the liver, respiratory lymph nodes as well as from the tracheal swabs of some of the sacrified animals (8 out of 18 swabs).