﻿IX, B, 6 Barber: Milk Poisoning 517 



hours an attack of gastroenteritis followed, similar in all details 

 to the ones experienced on the farm, but somewhat more violent 

 than any of them. The cramps and faintness, especially, were 

 pronounced. The more violent symptoms disappeared within 

 seven or eight hours, although slight cramps persisted much 

 longer. The next day there remained only malaise and a slight 

 digestive disturbance. 



The evidence, then, is conclusive that the illness is due to a 

 poison formed by the white staphylococcus in milk. The yellow 

 staphylococcus, apparently, is unable to produce this toxin. 



The white and the yellow staphylococci from the suspected 

 cow were compared on various media, including some 12 different 

 litmus agars. The cocci of the white form are somewhat smaller 

 than those of the other, and show a greater tendency to form 

 diplococci. Cultures further differ in that the white strain 

 formed acid on mannite and maltose litmus agars, while the 

 yellow did not. Both ferment lactose, but the white in a less 

 degree than the yellow. Agglutination tests were made with 

 my serum after 5 attacks of the illness and within one 

 month after the last attack. The yellow form gave complete 

 agglutination in dilutions from %o up to Vso. differing in various 

 tests, while the white never gave it in dilutions higher than Y^q. 

 In a test with the serum of a resident of the farm, who was 

 tolerant of the poison, the white form failed to give complete 

 agglutination in a dilution higher than %(,. 



Inoculated subcutaneously into guinea pigs and monkeys, the 

 white form gave decidedly more reaction than the yellow — ^in 

 some cases abscesses were formed by it, which later healed. 

 Rabbits have resisted doses of the white variety up to 0.3 cubic 

 centimeter of an 18-hour broth culture, given intravenously. 

 Kittens, pups, and monkeys show no symptoms on ingesting 

 large quantities of milk cultures of the white staphylococcus ; or, 

 at all events, the symptoms are very slight. A goat fed with 

 3 slants of the culture showed no cocci in the milk. 



The cow from which the toxin-producing staphylococcus was 

 obtained is of mixed breed. She was imported from Australia, 

 and came into the possession of the present owner in 1909. She 

 has been immunized to Texas fever and has had rinderpest and 

 foot and mouth disease, all previous to 1909. In 1910 she had 

 garget in one quarter of the udder, but has been apparently 

 healthy since. It is noteworthy that the quarter which suffered 

 from garget has shown few or none of the toxin-producing sta- 

 phylococci, while this organism occurred in nearly pure culture 



