Kaschula, V.R.; Alexander, R.A.; Clark, R.; Louw, J.G.; De Kock, V.E.
(Published by The Government Printer, Pretoria, 1952)
When virus was dosed per os with virulent Newcastle disease virus and daily
examinations were made of virus in their pooled faeces, virus was recovered on
the 12th day.
No H.I antibodies were produced. The challenge ...