ACUTE MAMMITIS. 575 



The animals lose appetite and fall away rapidly. 

 Resolution may occur after from five to eight days. By degrees 

 all the symptoms then become less marked. The appetite returns, 

 pain diminishes, the fever drops, and the lesions gradually disappear, 

 but the yield of milk rarely regains its former amount. 



Suppuration may occur ; sometimes a superficial subcutaneous 

 abscess forms, more rarely, a deep-seated, interstitial abscess, originat- 

 ing in the connective tissue or lymphatic spaces. With a superficial 

 abscess, the local symptoms again revive to a slight extent ; these are 

 present in a more marked degree where the abscess is deep-seated. 

 An extremely sensitive oedematous swelling forms, the skin covering 

 which is at some point of a deep -red tint, whilst fluctuation gradually 

 appears. 



In cases of deep-seated abscess formation the general condition 

 becomes alarming ; the affected quarter is tense throughout, hard and 

 very sensitive. 



Deep-seated suppuration is difficult to detect, and exploratory 

 punctures with a fine needle may be necessary before the diagnosis 

 can be made. 



Local or diffuse gangrene forms a rare complication. It is due to 

 the vessels of one or several glandular lobules becoming obliterated 

 or thrombosed. 



Such a termination is indicated by extreme aggravation of the general 

 symptoms, feebleness of the heart and great weakness of the i^atients, who 

 fall into a condition of coma. Locally the udder remains oedematous, 

 the skin becomes of a blackish-violet colour, whilst the local temperature 

 falls and the animals die from exhaustion and intoxication. 



Parenchymatous Mammitis. — Parenchymatous mammitis when 

 mild is also termed catarrhal mammitis. It is in reality true 

 primary mammitis ; interstitial being primarily and practically peri- 

 mammary lymphangitis. 



In this case infection occurs through the teat, and may be localised 

 in the sinus or excretory apparatus, giving rise to galactophoritis, but 

 it usually extends to the acini. Inflammation of the mammary tissue 

 is therefore direct and primary. It rapidly extends, however, through 

 the glandular wall into the interstitial tissue, thus setting up (from 

 the anatomo-pathological standpoint) a mixed mammitis. Clinical 

 distinction between this form and interstitial mammitis is at first 

 easy. 



The symptoms usually occur in the following order : — Swelling of 

 the affected quarter or quarters ; appreciable increase in size and 

 sensitiveness; the presence at first of curdled milk in the galacto- 

 phorous sinus, then of clots mixed with slightly red tinged serosity; 



