112 ANNUAL REPORT OF THE Off. Doc. 



since ]89(;. WUh this ciilLuii' a lu-ifer, two years old, and a younj; 

 calf were inoculated intravenously. The calf was killed after thirty- 

 two days, and showed a typical eruption of minute tubercles all 

 through both lungs, but especially marked in the anterior lobes. 

 The heifer was kept for one hundred and twenty days, and was only 

 sligflitly diseased, the lungs and" pleurae being involved. With the 

 second culture, obtained from a case of pleurisy, a calf two and one- 

 half months old was inoculated intravenously. Death ensued after 

 seventeen days. The lungs alone were involved, showing many 

 young nodules. The third culture was isolated from a case of pleu- 

 ropericarditis, with involvement of the lungs, and wdth this a young 

 bull convalescent from aphthous fever was inoculatedi intravenously, 

 death resulting in thirty-two days. The thoracic cavity was prin- 

 cipally involved, the anterior and middle lobes containing nodules 

 througlhout, and some lobules of the posterior lobes al»o. The 

 bronchial and esophageal glands were tremendously enlarged, weigh- 

 ing thirty-five kilograms. 



It may be objected to many of these experiments that the tubercu- 

 losis resulting from, the inoculation did not cause death nor even 

 serious illnese, and it is probable that some of the animals would 

 have recovered entirely if allowed to live. Admitting freely the 

 truth of this, it may be pointed out that under natural conditions 

 many cattle infected with bovine tuberculosis will remain for years 

 apparently in perfect healtih, so much so that detection of the disease 

 is possible only by means» of tuberculin. So, also, in man, many 

 cases of tuberculosis run a benign course, or remain stationary for 

 years, while not a few end in recovery. Yet in man and in animals 

 these benign cases may take on an acute form and end in rapid death, 

 owing to some intercurrent affection which lower® resistance or per- 

 mits the engrafting of a secondary infection. No one would hold 

 that because of the benign course of the disease in the first instance 

 that true tuberculosis did not exist. 



Transmission of Tul)ercnlosis to Cattle from Phthisical Attendants. 

 — There are on record a few instances of cattle becoming infected 

 with tuberculosis through tihe sputum of phthisical attendants. In 

 several of these the evidence is so clear as to leave no doubt that cat- 

 tle art at times infected in this manner. Such instances have been 

 reported by Cozette, Clique, Huon, director of the vacine lab- 

 oratory at Marseilles, and Bong. I*i most of these cases the sputum 

 was introduced into the digestive tract with the forage, as well as 

 inhaled in the dry state, but in Huon's animal the infection seems 

 to have been entirely tihrough inhalation. 



Experiments at the Laboratory of the State Live StocJc Sanitary 

 Board.— 1 come now to speak of the work done at the laboratory of 

 the State Live Stock Sanitary Board, the results of which you see 



