;{') MASS. EXPERIMENT STATION BULLETIN '273 



in tlie riiiia glottis. The comb and wattles ajipeared cyanotic. T!ie 

 temperature of tlie liird was 107° F. On l)eceiid)er 2, tlie teiiii)eratiir»' 

 was 106.7° F. The cockerel died the following day. The carcass was 

 emaciated and anemic. An examination for gross pathology revealed 

 desquamative epithelial inflammation of the trachea, leaving the mucosa 

 dry and grayish-yellow in color. The syrinx wa.s occluded with dried 

 exudate. Enteritis was marked. The intestinal wall appeared hyperemic 

 •and necrotic in places. The tissues of the lungs, liver, and kidneys were 

 hemorrhagic. Histopathological sections revealed fibrinous inflammation 

 of the mucosa and submucosa of the trachea; congestion and hemorrhagic 

 inflammation of the lungs; cloudy swelling, and foci of hyjierplasia of 

 histiocytes in the liver; cloudy swelling and hemorrhagic inflammation 

 of the kidneys and spleen. Sections of the lesions in the intestinal wall 

 manifested hyperemia, necrosis, and foci of hyperplasia of reticuloendo- 

 thelial cells with lymphoid infiltration. Some of the hyjierplastic areas 

 showed diffused inflammation. 



From this study of infectious trachitis in the four cockerels, it was 

 found that the disease was both infectious and easily transmitted from 

 diseased to healthy birds by intratracheal inoculation. The incubation 

 period and the length of time that the cockerels lived after inoculation 

 with this virus varied as follows: 



* Killed. Omitted fi-om the average. 



The uniformity of symjitoms and pathological lesions in all four cock- 

 erels, following inocxdation, demonstrated that the Granby virus was a 

 pure strain of infectious trachitis. The symptoms and pathological lesions 

 were in general typical of the disease as found in ail of the birds studied 

 in this investigation. 



These studies further indicated that the degenerative changes in the 

 mucosa and submucosa were not severe as long as the ejiithelium remained 

 intact or was ])romptly rejtlaced by a ])seudomend)rane to jirevent liemor- 

 rhages and secondary' microbial infection uhich often lead to necrosis 

 and suppuration. 



The Second Transfer of the Granby Virus. 



A White Leghorn cockerel and two liarrcd Piynioiitli Hock fowls were 

 inoculated November 27, lU'.iO, witli a jiooled \irus from the tracheas of 

 VP 880 and VP 882 to determine wliether this virus coiiiii be projiagated 

 under laboratory conditions in fowls, since younger birds were not avail- 

 able at this time. The results of these inocidations are rejiorted in Table L 



The Granby virus had retained its ))otency sufficiently in this second 

 transfer to kill cockerel VP 88.5 and fowl .'30991, and to cause serious ill- 

 ness in fowl 30992. 



