Response of Syrian Hamster to the Virus of Newcastle Disease by Intratesticular Injection

Abstract

FOLLOWING the adaptation of Newcastle virus, California strain No. 11,914, to the Syrian hamster by intracerebral injection and intranasal instillation, Reagan et al. (1949a) and intradermal injection, Reagan et al. (1949b) attempts to transmit this modified virus by testicular injection were made in older hamsters.Newcastle virus from the 300th intracerebral hamster passage was prepared from 6 virus infected hamster brains. These brains containing virus were removed aseptically, ground with alundum, and diluted to a 20 percent suspension with physiological saline solution. This virus brain suspension titered 10−4 by intracerebral inoculation in 4-week-old hamsters (average weight 28 gm.). Approximately 0.06 ml. of this virus brain suspension was injected into each testicle of each of four 35-day-old hamsters (average weight 40 gm.). In hamsters responding to the virus injection, irritability and malaise appeared in 6 to 10 days after testicular injection. In most cases these symptoms were followed by paralysis, excessive .