416 DISEASES OF CATTLE. 



those who have giAen this subject special attention, the udder be- 

 comes swollen uniformly and quite firm. This swelling, Avhich is 

 painless, frequently attacks but one quarter, more rarely tAvo, these 

 being usually the hind quarters. The larger milk ducts contain yel- 

 lowish, cheesy particles, in which are many tubercle bacilli. Later 

 larger nodules can be felt within the udder, which undergo the 

 A'arious changes to which tubercles are subject. The udder may grow 

 very hard to the touch and become very large, Aveighing in some cases 

 up to 40 pounds. The milk, at first normal, becomes thin and watery 

 after a month or so, and is mixed with flakes and tubercle bacilli. 



As regards the frequency of the tuberculous processes in the dif- 

 ferent organs, the folloAving carefully compiled statistics of the 

 disease in BaA'aria and Baden may serA'e as a guide : 



Bavaria : Per cent. 



Tuberculosis of lungs and serous membranes 41 



Tuberculosis of lungs alone 33 



Tuberculosis of serous membranes alone (pearly disease) 17 



Tuberculosis of other organs 8 



Baden : 



Tuberculosis of lungs alone 21 



Tuberculosis of serous membranes alone 28 



Both combined 39 



Generalized tuberculosis 9 



Tuberculosis of the sexual organs alone 3 



SymptPTivs. — The beginning of the disease usually passes unnoticed, 

 inasmuch as it is very sIoav and insidious and rarelj^ accompanied Avith 

 fever. A^Hien the lungs are involved a dull, short cough is noticed, 

 Avhich may later on become prolonged, convulsive, and very trouble- 

 some to the animal. The cough is more frequent in the morning 

 after movement and drinking. The breathing varies. Only when 

 much of the lung tissue is diseased is it labored and accompanied 

 Avitli active movements of the chest and nostrils. Discharge from the 

 nose is rare or absent. At times, however, Avhen the tubercles haA'e 

 broken down and cavities containing chees}^ masses have formed in 

 the lung tissue, or when the air tubes have become filled with cheesy 

 and mucous masses, coughing Avill dislodge them and cause their dis- 

 charge. In advanced stages the breath may haA^e a disagreeable odor. 

 Pressure on the chest wall may giAe rise to pain. 



The general effect on the body is at first slight. In fact, animals 

 may remain in good flesh for a considerable time. Invariably as the 

 disease progresses loss of flesh and appetite and paleness of the 

 mucous membranes become manifest. These symptoms are accom- 

 panied Avith a gradual diminution of the milk secretion. The de- 

 bilitated condition of the animal is also manifested by a staring coat 

 and a tough, dry, harsh skin (hidebound). DigestiA^e disturbances 

 are indicated b}^ tympanites, or distention of the rumen by gas, colic, 



