Congestion—i.e., distension of the vascular plexus as a consequence of momentary stasis, vaso-motor disturbance, or paralysis of the little vessels in the udder—can only be regarded as pathological in cases when it precedes mammitis or when it results from prolonged neglect to milk the animal, external irritation, etc. It was studied long ago by H. d’Arboval, Gellé, Delafond, Trasbot, Lucet, etc.
It also occurs, but in a form which might almost be termed physiological, after the first parturition in the large milch breeds, where the rush of blood which precedes secretion is very great.
Symptoms. The udder is swollen, tense, doughy, shining, and œdematous, not very painful on pressure, but sufficiently so to interfere with movement. The general condition is little altered, but the temperature of the udder is abnormally high.
Manipulation reveals the existence of more or less œdema, the parts preserving the imprint of the finger. Sometimes this œdema extends along the abdominal wall in front of the udder. The milk may be grumous or even sanguinolent. The congestive state continues for some days, eight to ten at the most, and may gradually disappear by resolution. Not infrequently it terminates in acute mammitis after forty-eight hours.
Lesions. In simple mammary congestion the lesions are confined to excessive dilatation of the peri-acinous capillary vessels, and extravasation into the connective tissue. On section the tissue has a dark-red appearance.
Diagnosis. The diagnosis is simple.
Prognosis. The prognosis is less alarming than might at first sight be supposed.
The treatment consists simply in hygienic precautions, frequent milking, emollient, sedative applications to the udder, and frequent washing. As far as possible the use of milk catheters should be avoided.
Boric vaseline and belladonna ointment may be recommended. In very serious cases blood can be withdrawn from the jugular. This is better than bleeding from the mammary vein, which always entails the risk of thrombus formation.