KCTIOUS DISEASES OF CATTLE. 405 



Lydtin quotes the following description of the disease as taken from a 



.Swiss sanitary order: 



A dry, short, interrupted, hoarse cough, -which the sick animals manifest espe- 

 cially in the morning at feeding time, still more after somewhat violent exertion. At 

 tir>r these animals may be full-blooded and lay on a considerable amount of fat 

 when well fed. As the disease progresses they grow thin and show more and more 

 those appearances which indicate diseased nutrition, such as a staring, lusterlesa, 

 disheveled coat; dirty, tense skin, which appears very pale in those regions free 

 from hair. The temperature of the skin is below normal. The loss of fat causes 

 sinking of the eyes in their sockets. They appear swimming in water, and their 

 expression is weak. The- cough is more frequent, but never or very rarely accom- 

 panied with discharge. The body continues to emaciate even with plenty of food 

 and a good appetite, so that the quantity of milk is small. At times, ir the early 

 stages of the disease, still more in the later stages, the diseased animals manifest 

 considerable tenderness when pressure is applied to the front or the sides of the 

 chest, by coughing, moaning, etc. Often all symptoms are wanting in spite of the 

 existence of the disease. 



Lydtin also quotes at length a description of the abnormal sexual 

 desire occasionally observed among cows when affected with this dis- 

 ease. ^ ' 



Diagnosis. A disease so varied in its attack upon the different 

 organs of the body and in the extent of the disease process must neces- 

 sarily lead to mistakes of diagnosis. It has been confounded with the 

 later stages of pleuro-pneumonia, with parasitic diseases of the brain, 

 the lungs, the intestines, and with actinomycosis. In the early stages 

 of the disease diagnosis is very difficult. The various procedures 

 which have been suggested from time to time are all based on the 

 detection of the tubercle bacilli, .and therefore can only be made use of 

 by trained veterinarians. At present a method is under trial which 

 may bo destined to solve the difficulty. It consists in injecting beneath 

 the skin a certain quantity of a liquid which represents an extract of 

 tubercle bacilli. In cattle which are tuberculous, even to a slight 

 degree, an elevation of temperature or a temporary fever will follow 

 'the injection. In those which are healthy no such reaction takes place. 

 Whether the method will prove to be all that it promises can not be 

 definitely stated at this time. If it should it will be a great assistance 

 to the veterinarian in the detection of this disease. 



Treatment of the disease is not seriously considered by any authori- 

 ties at the present time. 



The measures to be adopted to prevent the spreading of the disease 

 must take into consideration not only the tubercle bacillus, but like- 

 wise all those circumstances which make cattle more susceptible to the 

 <ii-ease, which have already been dwelt upon. It would be useless 

 to repeat here all that has been said above on the transmission of tuber- 

 elr bacilli from one animal to another, and on the dangers of certain 

 debilitating influences. A careful study of these will show how tuber- 

 -ulosis may, at least in some cases, be prevented. The difficulty of 

 determining when cattle first become tuberculous makes it imi>os8ible 

 to prevent the legibility of infection. Great care should therefore be 



