Anatomical Changes. Symptoms. 67 



Haase found, 2 to 4 weeks after the disappearance of the disease, small dark 

 red areas in the kidneys and in the later stages, purulent nodules, sometimes accom- 

 panied by extensive inflammation of the kidney tissue. 



The blood vessels, corresponding to the red spots of the 

 skin, appear dilated, filled with blood, while the skin and sub- 

 cutaneous connective tissue is edematously infiltrated and 

 studded with small hemorrhages. The muscles either appear 

 healthy or they are grayish red and lustreless, while the inter- 

 muscular connective tissue may be edematous. In rare cases 

 certain parts of the body (ears, tail, nostrils, etc.) or larger 

 areas of the skin may be necrotic (e. g., on the back). 



In the chronic form the disease manifests an endocarditis 

 (verrucosa or ulcerosa) in the majority of cases. In one or 

 more orifices of the heart, particularly in the left arterial ori- 

 fice, the convex surface of the valves is covered with a cauli- 

 flower-like fibrin coagulum which sometimes reduces the orifice 

 to such an extent that it is hardly possible to insert the quill 

 of a pigeon feather. After the removal of the fibrin deposit 

 small wart-like vegetations or ulcerations appear on the thick- 

 ened valve. Such carcasses also manifest the secondary changes 

 which are usually produced by affections of the heart, such as 

 hydrothorax, passive hyperemia of the lungs, liver and spleen, 

 infarcts of the kidneys, etc. 



In some cases the autopsy also reveals chronic enteritis, 

 hypertrophy of the lymph glands (without necrotic areas), 

 small necrotic foci in the liver and chronic inflammation of the 

 serous membranes as well as of some of the joints. 



The bacilli may be demonstrated easily in acute cases in the blood in the 

 capillary vessels of the internal organs (especially spleen, liver and kidneys), in 

 the lymph spaces of the skin, and the subcutaneous connective tissue, in the red 

 areas of the skin and plaques, as well as in the regional lymph glands. In the 

 blood they are present either free in the plasma or inclosed in the leucocytes. In 

 chronic cases the bacilli are usually only present in the afEected tissues, particularly 

 in the valves of the heart and in the fibrin coagulum as well as in the bile where 

 they remain for a longer time even after the acute affection has subsided (Kitt). 

 With Gram's stain they may be demonstrated even in putrefactive tissues (Opalka, 

 Eosso). However, it Is advisable to cover the parts of organs with salt in order to 

 prevent putrefaction when shipped for laboratory examination. 



Symptoms. The time of incubation of erysipelas after arti- 

 ficial inoculation is 3 to 5 days (Preisz, Kitt). After natural 

 infection from the ingestion of infectious meat or of contami- 

 nated water the first indications of the disease appear as early 

 as 24 hours, otherwise the time of incubation is usually 3 to 

 5, and exceptionally probably as long as 7 days. 



The clinical symptoms show a considerable variance in 

 different cases; in general the following three readily distin- 

 guishable forms of the disease may be observed which may also 

 differ from each other in their course. 



1, Urticaria (Diamond-skin disease) represents the mild- 

 est form of erysipelas. In its course the animals show after 

 1 to 2 days a disturbance of their general health, and sharp 



