MASS. EXPERIMENT STATION BULLETIN 27;i 55 



10. Coniparative studies of infectious tracliitis from Massachusetts, 

 California, and New Jersey sliowed iniiminological differences between 

 acute and chronic cases. 



11. Tiie virus of tlie second California strain of infectious tracliitii 

 was deiTU)iistrated in the macerated tissues of tiie liver, si)lecn, trachea 

 jMid kidney of ciiickens dead of the disease. 



12. Two healthy carriers of infectious trachitis were found, in \\hich 

 tl.c virus remained viable in the tracheal exudate for two and four weeks, 

 respectively, after all visible symptoms of the disease had disappeared. 



13. The virus of infectious trachitis was deiminstrated in tlie cloacal 

 contents of three of tlie birds infected with the first California virus and 

 four of the cockerels and ])ullets suffering from an infecti(m with the first 

 New Jersey strain. 



IL Chickenpox vaccination did not protect domestic fowls afjainst 

 infectious trachitis. 



Bibliography 



Cooper, LIujih. 1!)2!>. llanikiiet disease: A new disease of fowls in India 

 due to a filter-jiassinji' virus. Imp. Inst. Vet. Res. Muktesar-Kumaun, 

 L^nited Provinces, India, Ann. Rpt. year ending Mar. .31. 



Doyle, T. M. 1927. A hitherto unrecorded disease of fowls due to a 

 filter-passing virus. Jour. Compar. Path, and Ther. 40:14.4-169. 



Ilinshaw, W. R. 1!)25. Studies in poultry diseases found in ]ioultry feed- 

 ing stations. Nat. Poultry, Butter and Egg Bui. 9(l-a):.3-f). 



Illinois Agricultural Experiment Station. 1929. Work with diseases of 

 poultry at the Illinois Station. 111. Agr. Expt. Sta. Ann. Rpt. 42:116-119. 



Kee, Francisco Go. 1928. Notes on an outbreak of poultry epidemic. 

 Philippine Agr. 17:263-265. 



Kernohan, George. 1930. Infectious bronchitis in fowls. Calif. Agr. 

 Expt. Sta. Bul. 494. 



May, Henry G., and Tittsier, Ralph I'. 1925. Tracheolaryngitis in jiou!- 

 try. Jour. Amer. Vet. Med. Assoc. 67(N. S. 20): 229-231. 



Swift, Homer F. 1921. Preservation of stock cultures of bacteria by 

 freezing and drying. .lour, b'.xpt. Med. 33:69-75. 



Acknowledgments 



In conclusion the autitur v\ishcs to extend Ids sincere thanks to Profes- 

 sor William H. Davis. Botany Department, Massachusetts State 

 College, for cooperation in taking the nucrophotographs showing the lesions 

 of infectious trachitis, and to Doctor J. R. Beach, L^niversity of California, 

 f.nd the Rockefeller Institute for Animal Diseases, for contributing the 

 California and New Jersey strains of infectious trachitis. 



Doctors Henry Van Roekel, G. L. Dunlap, and Professor William C. 

 Monahan contributed viruses at critical times during the course of this 

 study. This assistance was appreciated. 



