576 DISEASES OF THE MAMMARY GLANDS. 



complete cessation of the yield of milk, and suppuration in the 

 secreting portions of the gland. 



The general symptoms appear only after the objective signs, and 

 vary greatly in intensity, according to the ease. As in 'the interstitial 

 form, there may be marked fever, loss of appetite, cessation of rumi- 

 nation, groaning, and difficulty in walking. 



In some grave forms, where development is peracute, infection 

 spreads rapidly from the glandular to the interstitial tissue, and 

 subcutaneous, sub-abdominal, or perineal interstitial cedema occurs 

 secondarily. 



The udder is turgid, tense, shining, and of reddish-violet colour in 

 places, as if a deep-seated abscess were developing. 



Pressure on the galactophorous sinus causes the flow of reddish-grey 

 milk, sometimes fcetid or of gangrenous odour. The animals seem 

 exhausted, show signs of profound intoxication, are unable to rise, and 

 appear paralysed. 



But besides these grave forms are others, in which the patients seem 

 scarcely to suffer : appetite is preserved and all the vital functions are 

 in full activity. Only the local signs are of importance. 



This variability in the clinical symptoms of acute forms of mammitis 

 is entirely due to differences in the pathogenic infecting organisms. 



Parenchymatous mammitis may end in resolution in three to four 

 days, with progressive but slow return to the physiological condition. 

 This termination is announced by the gradual disappearance of all 

 the symptoms and the return of milk secretion. It is, however, quite 

 exceptional for the former condition to be fully restored, and in many 

 cases the affected quarter must be regarded as lost from the physio- 

 logical standpoint. 



It gradually becomes hardened, sclerotic and atrophied. 



Suppuration is very common. It attacks the galactophorous sinus, 

 the excretory canals, and even the acini. If obstructions occur in the 

 course of the collecting vessels, or if evacuation is not artificially 

 .stimulated by milking, the pus collects in the depths of the gland, 

 and enormous diffuse abscesses may form at the expense of the 

 mammary tissue. 



Circumscribed or diffuse gangrene, as a primary condition, is rarer. 

 Infective organisms rapidly invade even the depths of the gland, the 

 interstitial and subcutaneous tissue, and thrombosis due to infection 

 or intoxication occurs, followed by gangrene. Death results from 

 infection or intoxication. 



Complications such as necrosis of the abdominal tunic, of the 

 fibrous tissue enveloping the mamma, and of the muscular layers on 

 the inner surface of the thighs, may occur in the suppurative forms. 



