UDDER-STAPHYLOMYCOSIS 57 



I have not seen bactersemia in laboratory animals, al- 

 though it may be produced in dogs. At the point of inocu- 

 lation, however, the organism can be found. 



Autopsy of cases which have run an acute course shows 

 only an oedematous swelling at the point of inoculation 

 and no distinct lesions elsewhere. 



Mice, dogs and pigeons may be killed in one day by an 

 organism of high virulence. 



Cows. — Twelve c.c. of a one-day-old culture of staphy- 

 lococci which had previously been isolated from a severe 

 case of mastitis was injected into one teat of a milch cow 

 about six months after parturition. This staphylococcus 

 had been preserved in culture for sixteen months sealed 

 with paraffin and kept from the light. An abscess was 

 produced at the point of inoculation in a control mouse. 



Before inoculation the quarter of the udder showed no 

 alterations. The milk was of normal appearance but less 

 in quantity and showed a yellow sediment consisting of 

 a few pus cells and streptococci. 



Four hours after inoculation the body temperature was 

 39.1° C. [102.2° F.]. 



On the day following the infection the animal was 

 free from fever. The quarter was moderately swollen and 

 was more firm to the touch than usual, but not painful. 

 The quantity of milk was reduced and the milk yellow 

 and thick and contained a copious sediment composed of 

 yellow pus, staphylococci in great numbers and some strep- 

 tococci. 



Two days after the inoculation the milk was yellow 

 and thick and contained a moderate amount of sediment 

 consisting of yellow pus and frequent chains of cocci. It 

 was otherwise the same. 



Three days following infection the milk was whitish- 

 gray and flocculent and presented a moderate quantity of 

 sediment consisting of yellow, fibrinous pus and a moderate 



