INFECTIOUS TKACHITIS 



51 



Intravenous Inoculation with the First and Second New Jersey Viruses 



On July 2.5, 1930, Rhode Island cl.iokens MA 31000, MA 94488, MA 

 04492, and MA 94494 received intravenously 1 cc. of Seitz filtrate from 

 chickens V 2240 and V 2280, which had died of infectious trachitis fol- 

 lowing intratracheal inoculations with the second New Jersey virus. Th'ese 

 chickens did not contract infectious trachitis as a result of the intravenous 

 injections, but were living and in good health three months after the treat- 

 ment. The control chickens, MA 9448.5 and MA 94487, inoculated intra- 

 tracheally with the same filtrate, at the same time, died of acute in- 

 fectious trachitis four and five days, respectively, after inoculation. 



MA 94498 and MA 94499 were injected intravenously with 1 cc. of 

 Berkefeld filtrate of the first New Jersey virus of infectious trachitis from 

 chicken V 224.5. These chickens remained healthy and well for three 

 months without showing any indications of disease. However, the con- 

 trols, MA 94493 and MA 94497, inoculated intratracheally with the same 

 filtrate, died of acute infectious trachitis in five and seven days, respec- 

 tively. 



Apparently virus of sufficient strength to kill birds inoculated intra- 

 tracheally, has no effect when injected intravenously. 



The Viability of Infectious Trachitis Virus 



From the beginning of these exi)eriments it was evident that the virus 

 of the tracheal exudates could not be depended upon to maintain its 

 virulence, for susceptible birds, for more than twenty-four hours at room 

 temperature, or three days in tiie ice box. However, viruses preserved 

 by the Swift (1921) method maintained their potency much longer. The 

 longest period of viability for the first California virus was two months 

 and twenty-six days, while the shortest was two weeks. The average was 

 four weeks and two days as indicated in Table 23. One of the first New 

 Jersey strains, which was especially virulent, maintained its ]iotency for 

 three months when jireserved by the Swift method. The average was 

 four weeks and five days (Table 23). 



Table 23. — Viability of infectious trachitis virus under different 



conditions. 



Virus 



Transfer 



Room 

 temjierature 



Ice box Swift method 



Granby I 



{ 



Amherst 



Califcjrnia I 



New Jersey I 



30* 



* .Average. 



