BIBLIOGRAPHY. 
203 
BIBLIOGRAPHY. 
INOCULATION PREVENTIVE DE LA PLEURO-PNEUMONIE AU POIN1 
DE VUE PRATIQUE. 
Par Er>. Dele, Medecin Veterinaire. 
This little brochure is the resume of a number of close observa¬ 
tions made by M. Ed. Dele, and of the conclusions to which he 
has arrived, viz: A strong advocacy of inoculation for the pro- 
philaxy of contagious pleuro-pneumonia. After giving a full de¬ 
scription, with tables, of the different experiments and observations 
he made, and also a few remarks about the process of inoculation, 
the choice of the virus, and the local and general effects obtained, 
Mr. Ed. Dele concludes as follows : 
Pleuro-pneumonia has generally appeared in a herd in one cow 
only , seldom upon two at a time, and in this case together. About 
three weeks after one, two or three new cases have appeared, one 
after the other, and then other cases show themselves at differ¬ 
ent intervals. 
The period of incubation has then been, in the minimum, about 
three weeks. 
When two cases made their appearance a few days apart, we 
have inferred that a case anterior, of about three weeks, had 
already existed. 
When pleuro-pneumonia makes its appearance in a herd, the 
first case is never recognized at first, that is, in the first period. 
When other cases are present, the previous existence of known 
cases may engender suspicion of existence of the disease. 
Pleuro-pneumonia is introduced into a stable by contagion. 
Spontaneous development, if it exists, is;the exception. 
Pleuro-pneumonia is always contagious, though some bovine 
are refractory to the virus. 
Pleuro-pneumonia, when propagation has not been prevented, is 
constantly spreading from stable to stable, where they com muni- 
