CONTAGIOUS DISEASES. 815 



care that should be exercised in watchfulness. The seeds of the disease 

 once in the system, the incubation is only a question of time, and warm 

 weather will bring out the disease in all its intensity. But none of the 

 above symptoms are conclusive of contagious pleuro-pneumonia, for all of 

 them are seen in the non-contagious form of it. The history of the cases, 

 one after another coming down with the same disease without any apparent 

 reason for it in the way of exposure, the failure of the disease to respond 

 to treatment, and the peculiar post mortem lesions found in it are the 

 points to be relied upon in making a diagnosis. The characteristic post 

 mortem lesions can be determined only by a competent veterinarian of 

 experience with the disease. 



What to do. — As to remedial measures, it seems useless for the farmer 

 to resort to them, since this is a disease that the veterinarian alone can 

 cope with, and then only when perfect isolation may be had. The safest 

 and also the cheapest plan, is prompt killing and burial of infected animals, 

 thorough isolation of the rest of the herd, which should l)e fattened and 

 marketed for beef under veterinary inspection at the time of slaughter, to 

 determine what is fit or unfit for human food, and perfect disinfection of 

 the premises. In the matter of disinfection, the easiest, cheapest and best 

 way is to remove all animals from the barn or shed, and close it up tightly 

 and burn sulphur in it for a couple of hours; then open and air it, and 

 whitewash it thoroughly with lime. 



Prevention. — Proper quarantines of stock imported into this country, 

 for a period of time sufficiently long to decide for a certainty that no latent 

 contagion is hanging around them, say two months; destruction of all 

 affected animals; and isolation of those that have been exposed to the con- 

 tagion. Some very high authorities in Europe recommend inoculation of 

 those that have been exposed, and even of whole herds and dairies. It is 

 a disease, the occurence of which in an animal once, confers immunity from 

 subsequent attacks. It is found that inoculation does not always produce 

 the same disease, at least the disease produced by inoculation is not always 

 located in the same place, but the constitutional effect is produced with the 

 same result of immunity from subsequent attacks as the original disease; 

 and the proportion of deaths among inoculated animals is small as compared 

 with those who take the disease in its regular course. 



The conclusions arrived at by the Belgian Commission in regard to 

 inoculation, as stated by Prof. Gamgee, are as follows: 



"1. The inoculation of the liquid extracted from the lungs of an animal 

 affected with pleuro-pneumonia does not transmit to healthy animals of the 

 same species the same disease, at all events so far as its seat is concerned. 

 2. The appreciable phenomena which follow the inoculation are those of 



