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E. NOCARD. 
still the digestive glands were invaded by the common mi¬ 
crobes that came from the intestine. 
This experiment has then allowed us to reproduce perfectly 
the natural disease, with its most rapid form, and with lesions 
identical to those that are found in the post-mortem of calves 
that died the day or the one after their birth. 
It shows besides, with evidence, the pathogeny of those 
secondary microbian infections, which are the rule in white 
scour as in other pasteurellosis and will in the slow form of the 
disease make the research of the original microbe so difficult.* 
The calf B, on the contrary, continued to be well. Yester¬ 
day, 20th of April, he was gay, strong and drank his milk with 
relish. His case is very interesting. It shows that a first at¬ 
tack, followed by recovery, gives a good immunity, at least 
temporary ; it shows the possibility (theoretical at least) of vacci 
nating calves against white scour; but practically, vaccination 
would be difficult, the march of the disease being so quick that 
it often kills calves the day after their birth or the next. 
The solution of this problem must be had elsewhere. 
This double experiment confirms in a very happy way the 
bacteriological study of the products taken at the post-mortem 
of the sick calves; it throws a strong light on the pathogeny 
of the disease. 
Whatever may be the door of entrance of the specific mi¬ 
crobe—and I am convinced that, in the majority of cases, it 
enters by way of the wound which results from the rupture of 
the umbilical cord—this microbe proliferates in the organisms 
and gives rise to a general affection which kills a calf some¬ 
times in less than 24 hours. It is a pure pasteurellosis, with 
septicsemic form. 
If the sick resists for several days—as it is the rule—the 
organism, deprived of the means of defense by the paralyzing 
action of the toxins of the pasteurella, becomes the prey of 
numerous secondary infections, proceeding from the intestines 
* The same experiment, made since on calves born at my laboratory in Alfort, 
where white scour has never existed, was followed by identical results. 
