DISEASES FOLLOWING PAETUEITION. 233 



unaffected side. With tlie increase in intensity and the extension of 

 the inflammation the general fever manifests itself more prominently. 

 In some instances the connective tissue beneath the skin and be- 

 tween the lobules of the gland is affected, then the swelling is uni- 

 formly rounded and of nearly the same consistency, pitting every- 

 where on pressure. In other cases it primarily attacks the secreting 

 tissue of the gland, then the swelling is more localized and appears 

 as hard, nodular masses in the interior of the gland. This last is 

 the usual form of inflammation occurring from infection entering by 

 the teats. 



In all cases, but especially in the last-named form, the milk is sup- 

 pressed and replaced by a watery fluid colored with blood (some- 

 times deeply) and mingled with masses of clotted casein. Later it 

 becomes white and purulent, and in many cases of an offensive odor. 



The course of the disease is sometimes so rapid and at others so 

 slow that no definite rule can be laid down. In two or three days, or 

 from that to the end of the week, the bag may soften, lose its heat and 

 tenderness, and subside into the healthy condition, even resuming the 

 secretion of milk. The longer the inflammatory hardness continues 

 the greater the probability that its complete restoration will not be 

 effected. When a portion of the gland fails to be restored in this 

 way, and has its secretion arrested, it usually shrinks to a smaller 

 size. More commonly a greater quantity of the inflammatory prod- 

 uct remains in the gland and develops into a solid, fibrous mass, caus- 

 ing permanent hardening (induration). In other cases, in place of 

 the product of inflammation developing into a fibrous mass, it softens 

 and breaks down into white, creamy, liquid pus (abscess). This ab- 

 scess may make its way to the surface and escape externally, or it may 

 burst into a milk duct and discharge through the teat. It may break 

 into both and establish a channel for the escape of milk (fistula). In 

 the worst types of the disease gangrene may ensue, a quarter or half 

 or even the whole udder, losing its vitality, and sloughing off if the 

 cow can bear up against the depressing influence. These gangi-enous 

 cases are probably always the result of infection and sometimes run 

 a very rapidly fatal course. I remember one to which I was called 

 as soon as the owner noticed it, yet I found one-quarter dark blue, 

 cold, and showing a tendency to the formation of blebs containing 

 a bloody secretion. The cow, which had waded through a depth of 

 semiliquid manure to reach her stall, died within 24 hours. 



Treatment. — Treatment varies with the type and the stage of the 

 disease. If the case is seen in the shivering fit, every effort should 

 be made to cut it short, as the inflammation may be thereby gTeatly 

 moderated, if not checked. Copious drinks of warm water thrown in 

 from horn or bottle; equally copious warm injections; the applica- 

 tion of heat in some form to the surface of the body (by a rug wrung 



