94 PRINCIPLES AND PRACTICE OF MILK HYGIENE 



Diagnosis of Tuberculosis of the Udder. For a time after 

 the disease has been established in the udder, the tubercles are 

 not large enough to be discovered by palpation and the milk 

 retains its normal appearance, but during this initial stage 

 of the disease symptoms are usually present in other organs 

 which enable one to discover the presence of the disease by 

 physical examination. In 119 cows affected with tuberculosis 

 of the udder, Lungwitz 21 found tuberculosis in other organs 

 in every one. The observations of Rick and of Joest and 

 Kracht, already quoted, show that the disease is usually gener- 

 alized when the udder becomes infected. 



Tuberculosis of the udder runs a slow, insidious course. 

 The perceptible changes in the udder which indicate its presence 

 are firm nodules, which are neither hot nor painful, or a rather 

 diffuse painless induration without local increase of tempera- 

 ture, in one or more quarters. Later, abscesses may form and 

 rupture (mixed infection) ; atrophy may also occur. The 

 posterior quarters are most commonly affected. The supra- 

 mammary lymph glands may be enlarged, while the udder is of 

 normal appearance, but in these cases the udder is usually also 

 infected. In rare cases, the disease runs an acute course, the 

 udder showing the symptoms of acute inflammation. 



In contrast with what occurs in other forms of udder disease, 

 the milk remains of normal appearance for eight to ten weeks, 

 although it may be highly virulent. Finally, it becomes thin 

 and transparent like water, assumes a yellowish color and con^ 

 tains small clots or flakes. When it is permitted to stand, a 

 pus-like sediment is deposited with a yellow, transparent fluid 

 resembling seruml above it. The acidity is reduced one-half 

 (Raudnitz), or the reaction is even sometimes alkaline (Oster- 

 tag). In advanced! cases, the secretion of milk ceases and' only 

 a purulent fluid in moderate amount can be obtained from the 

 affected quarter. 



Diagnosis of Open Tuberculosis. (a) Pulmonary Tubercu- 

 losis. The most characteristic symptom is a chronic cough, at 



21 Leblanc, Diseases of Mammary Gland (Nunn's transla- 

 tion). 



