114 



FARMER'S CYCLOPEDIA OF LIVE STOCK 



Two forms of disease — Quite re- 

 cently the announcement has been made 

 from several sources that there are two 

 forms of tuberculosis, both of which 

 may attack man. Much evidence has 

 been presented to show that the two 

 forms of the disease may coexist in the 

 human patient or in one of the domes- 

 tic animals. Dr. Raw and others have 

 come to the conclusion that tbe ordinary 

 form of pulmonary tuberculosis affects 

 primarily the lungs and is due to human 

 tubercle bacilli; while the intestinal 

 form of tuberculosis is largely due to 

 bovine tubercle bacilli, whether it oc- 

 curs in man or animals. Essentially 

 the same results have been obtained by 

 the German Imperial Health Office, 

 Theobald Smith and other investiga- 



organs the disease is characterized by 

 the development of tubercles varying in 

 size from that of a millet seed to that 

 of a hen's egg or greater. The contents 

 of these tubercles ultimately change 

 into a cheesy or calcareous mass and 

 such tubercles may be found in the lungs, 

 liver, spleen and intestines. As soon as 

 a case appears which is recognizable 

 by external symptoms, it is desirable to 

 apply the tuberculin test to the whole 

 herd for the purpose of ascertaining 

 whether the disease has spread to other 

 animals. 



Prevention of the disease — This 

 brings up the most important side of the 

 question, namely, that of preventing the 

 disease. In the work of eradication, 

 tuberculin is a very valuable reagent. 



62 — BEEF, TUBERCULOUS RIB ROAST. MINNESOTA 

 EXPERIMENT STATION 



tors. It appears, therefore, that the 

 human and bovine tubercle bacilli differ 

 in many respects, the bovine form be- 

 ing more virulent than the human form 

 and showing a greater tendency to pro- 

 duce infection of the intestines and 

 lymphatic glands. 



The symptoms of the disease in cat- 

 tle are often very difficult to recognize 

 in the early stages. The first noticeable 

 symptom of a chronic case is a dry 

 cough. The condition of the animal 

 slowly deteriorates and there is a loss 

 of flesh, accompanied wi + h an unhealthy 

 appearance of the coat. The disease 

 affects nearly all of the organs and tis- 

 sues of the body, but in individual cases 

 may be confined to one organ or a set 

 of neighboring organs. In the internal 



This substance contains the toxin or 

 poisonous principle of the tubercle ba- 

 cillus but none of the living bacilli. It 

 cannot, therefore, cause the disease in 

 living animals. When inoculated into 

 healthy cattle it produces no reaction 

 of any note. In tuberculous cattle, how- 

 ever, it causes an elevation of tempera- 

 ture of one to three degrees, together 

 with swelling at the point of inocula- 

 tion. In making the tuberculin test the 

 temperature of the animal should be 

 taken at intervals of about two hours, 

 for four or five times in order to de- 

 termine the average normal temperature 

 of each animal. After inoculation with 

 tuberculin, the temperature is again 

 taken at intervals of two hours or less 

 and if an elevation of two degrees is 



