150 ANNUAL REPORT OF THE Off. Doc. 



Ii'auniatisrn. It seonied to give a mode of infection closely resemb- 

 ling the natural one. One of the vaccinated cattle (450G8) was killed 

 October 4th. A searching post-moitem examination revealed all of 

 the organs, including their lymphatic glands and covering mem- 

 branes, to be free from all evidence of disease, with the exception 

 of a slight fibrous thickening of the wall of the jugular vein at the 

 point of vaccination. At the site of the intratracheal inoculation of 

 July 29th there was no mark, and the mucous membrane lining the 

 trachea was entirely normal. 



A control heifer (45071) killed October 8th showed the following 

 upon post-mortem examination: At the point of inoculation, upon 

 the outside of the trachea and beneath the skin, there was a globular 

 abscess about three-quarters of an inch in diameter, containing 

 cheesy pus. The mucous membrane of the trachea showed a num- 

 ber of small, reddish elevations (tubercular) below the point of 

 inoculation. The lungs were studded upon the surface and upon 

 cross section with grayish nodules one-quarter to one-half an inch 

 in diameter, the centres of which were caseous. These tubercles 

 were evenly distributed in both lungs and roughly averaged from 

 one to one and one-half inches apart. They could be plainly seen and 

 felt through the transparent pleura. The apex of the right lung con- 

 tained a caseous area two inches in diameter, which was made up 

 of manj' adjacent small tubercles. Tlie bronchial and mediastinal 

 lymphatic glands were enlarged and contained cheesy areas from 

 one-sixteenth to one-third of an inch in diameter. The post-pharyn- 

 geal lymphatic glands were enlarged to the size of an egg,hyperfemic, 

 and on section show^ed numerous caseous areas. 



The second vaccinated animal (45006) was killed October 16th. At 

 the two points of insection of the needle when the animal was inocu- 

 lated, July 29th, there were two somewhat hard, globular fibrous 

 thickenings one-quarter to three-fifths of an inch in diameter, respec- 

 tively. Within the trachea, and occupying positions corresponding 

 to these, were two very small tpin-hend) grayish elevations in the 

 mucous membrane. Upon section it was found that the upper of 

 these small thickenings was made iip of fibrous tissue, the lower (the 

 smaller one) contained a focus of caseous material surrounded by 

 thick, fibrous walls. The whole appearance was that of a closed 

 process. No other lesions were found in any part of the body. All 

 of the organs, their lymphatic glands and covering membranes, ap 

 peared to be quite normal. There was no thickening of the wall of 

 the jugular vein at the point of vaccination. 



The second control (unvaccinated) heifer (45067) was killed Oc- 

 tober 16th. The post-mortem report is as follows: Beneath the skin 

 in the middle of the neck, at the point of inoculation, there was an 

 abscess about two inches in diameter that contained cheesy pus. All 



