MILK-SCAELATINA. '2(^9 



Klein stated that on the teats and udders of two cows which 

 he investigated there were several flat irregular ulcers, varying in 

 diameter from one-quarter to three-qiiarters of an inch. Some 

 ulcers were more or less circular, others extended in a longitudinal 

 direction on the teat. The ulcers were covered with a brownish or 

 reddish-brown scab. The animals looked thin, but not strikingly so. 

 In feeding capacity, milking power, and body temperature there 

 was nothing abnormal. 



Four calves were inoculated in the corium of the groin and the 

 inside of the ear, with scrapings from the ulcers after removal of 

 the crusts. In one, which may h& taken as an example of the result 

 obtained, there was vesiculation at the margin of the spot inoculated, 

 and in the centre the commencement of the formation of a crust. 

 On the seventh day each sore on the ear had enlarged to about 

 half an inch in breadth, and was covered in its whole extent by 

 a brownish crust. On the eighteenth day they had all healed up 

 and become converted into flat scars. 



To search for micro-organisms, Klein removed the crust 

 from an ulcer on the teat, scraped off the most superficial layer, 

 squeezed the ulcer, and made cover-glass preparations. Tubes of 

 nutrient gelatine and nutrient agar-agar were also inoculated, and 

 a streptococcus was isolated which in m.orphological and cultural 

 characters agreed with those of Streptococcus pyogenes. 



Two calves were inoculated in the groin with the cultivated 

 micro-organism. One calf died in twenty-seven days. At the 

 necropsy there were found peritonitis, and hsemorrhagic spots on 

 the omentum ; the liver, kidneys, and lungs were congested, and 

 there were petechise under the pleura, and pericarditis. The second 

 calf was killed, and at the necropsy the lungs and kidneys were 

 congested, and there were hsemorrhagic patches on the spleen. 



In these cases, the post-mortem appearances and anatomical 

 features recalled to Klein the lesions of scarlatina. In the 

 kidney, for example, the cortex was congested, and there were 

 haemorrhages, glomerulo-nephritis, and granular or opaque swelling 

 of the epithelial cells and infiltration with round cells. From the 

 blood of the heart the streptococcus, which had been used in the 

 inoculation, was recovered. In view of this evidence it was con- 

 cluded that the streptococcus was the virus of the cow disease, and 

 that it produced in calves a disease very closely resembling that of 

 scarlatina in man. 



Two of the cows selected from the Hendon farm were killed, 

 and it was observed in one that the lungs were congested, and 



