340 PATHOGENIC BACTERIA IN MILK 



milk supply from two cows. Members of one household who did 

 not drink milk, or who used it only after sterilisation, escaped 

 infection. The cows yielding the milk were found to be suffering 

 from an eruptive disease of the udder, and both from the lesions 

 and from the milk, cultures of virulent diphtheria bacilli were 

 isolated. The pathological condition of the cows preceded by a 

 short interval of several days the onset of the disease in the 

 patients, and had the following characters : — On the udders and 

 teats of both cows there were present papules and ulcers, covered 

 by dark brown scabs. The papules were about the size of a pea, 

 and had an indurated base which extended into the subcutaneous 

 tissue. The majority of the lesions were in the form of ulcers 

 covered with dry brown crusts, and were of the size of a sixpence to 

 a shilling. On removing the crust from one of these there was 

 exposed a slightly moist, fairly smooth surface, with an elevated, 

 puckered, cicatricial-looking margin. The largest lesion, measuring 

 2 inches by i inch, was evidently formed by the running together 

 of smaller ulcers. In this case the ulcerative process was consider- 

 able. In one of the cows there was no mammitis, and abundant 

 secretion of apparently normal milk. In the other, there was, 

 in addition to the ulcerative lesions, mammitis affecting a posterior 

 quarter of the udder, and the milk was scanty, ropy, semi-purulent 

 looking, and slightly tinged with blood. Drs Dean and Todd 

 made a bacteriological examination of the material from the 

 ulcers and from the milk, and bacilli indistinguishable from those 

 of the Klebs-Loffler bacillus were isolated. The authors add that 

 "brushings were made from the teats of thirteen apparently healthy 

 cows at a small dairy farm. In two cases, the cultures on solidified 

 blood-serum showed diphtheria-like bacilli, but these on isolation 

 were proved not to be the B. diphtheric^" Experiments were also 

 made to determine the comparative virulence of the bacilli isolated 

 from the cows, the milk, and from the patient's throat. These 

 were each found to be virulent for guinea-pigs, and diphtheria anti- 

 toxin given simultaneously, or twenty-four hours before inoculation, 

 completely protected the experimental animals. The toxins from 

 these three races were also found to show a remarkable corre- 

 spondence in toxicity. 



The disease affecting these two cows, was by further experi- 

 ment shown to be readily contagious for calves. In the resulting 

 lesions of this animal, whether in the vesicular or ulcerative stages, 

 the diphtheria bacillus could not be found. Moreover, diphtheria 

 antitoxin (10,000 units) did not protect against infection in the calf. 



