54 THE LUNG PLAGUE OF CATTLE. 



market value, so that here they stand on precisely the same level with 

 the scrubs. Second, the owners of the thoroughbreds have expended 

 these high sums for their stock, and added proportionately to the wealth 

 of the State. The State is, therefore, called on to preserve these valuable 

 animals as well as the low-priced ones. Third, the indemnity, to be an 

 effectual adjunct to suppression of the disease, must be made^a stimulus 

 to the reporting of sickness, and whenever it fails in this through inade- 

 quacy or otherwise, it fails in the main object of its existence. 



INOCULATION FOE LUNG PLAGUE. 



For some years past this operation has been strongly advocated in 

 England and Holland, not only as a palliative of the losses from lung 

 plague, but as a means of stamping out the disease. In a report like 

 the present, which is intended to furnish a sound basis for intelligent 

 legislation, it becomes needful to canvass this truly important question. 



In December, 1850, Louis Willems, M. D., of Hassalt, Belgium, son of a large dis- 

 tiller, began his essays on inoculation. To determine the susceptibility of different 

 animals, he inoculated with the exudation matter from diseased lungs 6 rabbits, 23 

 pea-fowls, a number of chickens, 4 dogs, 3 slieep, 7 hogs, and 2 goats, but in all the 

 wounds healed without any unhealthy action. These animals were accordingly set 

 down as insusceptible. Accidental wounds of human beings were equally harmless. 

 He instituted experiments on several cattle which he inoculated with the liquids from 

 healthy lungs. The result was only slight inflammation followed by healings. 



He inoculated three cattle, respectively, with bjood, buccal mucus and intestinal 

 tubercle taken from sick cows. These produced but slight inflammation, followed by 

 prompt recovery. 



He inoculated 108 cattle with the pulmonary exudation of diseased lungs. In a 

 period averaging fifteen days after inoculation a swelling occurred in most of these in 

 the seat of inoculation, and though afterwards kept in an infected stable all these 

 animals resisted the disease. Of fifty uninoculated animals placed in the same sta- 

 bles, seventeen became diseased. 



He further reinoculated ten cattle that had been already successfully inoculated, and 

 all the wounds healed promptly without any local swelling such as marked the other 

 cases from the tenth to the thirtieth day. 



In none of these cases was there any indication of disease of the lungs, and in a 

 number that were killed these organs were found healthy. 



He concluded that when the virus is inoculated on a susceptible animal, "a new 

 disease is produced ; the affection of the lungs with all its peculiar characters is lo- 

 calized in some sort on the exterior" ; and that this disease is preservative against all 

 future attacks of pleuro-pneumonia. 



Various commissions were appointed by different European governments to deter- 

 mine the matter by experiment. The Dutch commission, composed of the faculty of 

 the Veterinary School at Utrecht, reported in 1852, that out of 247 head of cattle inocu- 

 lated sixteen afterward contracted the disease, these being mainly composed of such 

 as had the least local swelling in the seat of inoculation. They reported that inocu- 

 lation had "a power, at least temporary, of securing against the contagion of pleuro- 

 pneumonia." 



The Belgium commission, presided over by Professor Verheyen, inoculated 197 cat- 

 tle, fourteen of which were afterward kept in stables with infected animals without 

 contracting the disease. 



The French commission, presided over by Professor Bouley, inoculated 54 cattle, of 

 which 48 survived and were made to cohabit with diseased stock. But one of those 

 contracted the plague. 



In England a commission was appointed, and, after a series of experiments in 1854-5 T 

 they reported adversely. 



Since that time inoculation has been adopted extensively in Europe, and still more 

 largely in Australia and South Africa, until to-day it is acknowledged by all who have 

 given attention to the subject that for the individual animals, it is as surely protec- 

 tive as is vaccination for small-pox, and that attacks of lung plague, after successful 

 inoculation, are little if at all more frequent than are second attacks of variola. (The 

 lung plague of cattle. Law.) 



It is not overstating the case to say that many hundreds of thousands 

 of cattle have now been subjected to the test of inoculation, many skill- 



