RESPONSE OF THE SWISS ALBINO MOUSE TO THE VIRUS OF NEWCASTLE DISEASE

Abstract

The hamster-adapted Newcastle virus (California strain no. 11,914) of the 300th passage has been successfully transmitted to Swiss albino mice and carried through 30 serial passages in this species by intracerebral inoculation. The mice respond nearly 100% when virus of this /later hamster passage is used rather than the 203d hamster passage virus, which was used in the previous trials. This mouse Newcastle virus produced similar symptoms in hamsters and mice by intracerebral inoculation. These symptoms were irritability and malaise, usually followed by paralysis and often accompanied by nervous jerking with labored breathing. This 30th mouse brain passage was confirmed to be Newcastle disease by neutralization tests in mice. The virus titrated 10-2.5 in mice.