CONTAGIOUS DISEASES OP DOMESTICATED ANBIALS. 391 



pork-producer, and swine-breeder. In other words, to ascertain as far 

 possible the means or media by which swine plague is actually and prin- 

 cipally spread from place to place, from herd to herd, and to learn by 

 observation and experiment what may be done by the indiAidual farmer 

 and swine-breeder to protect his herd, and to effectually prevent the 

 spreading of the plague, or to stoj) its progress, I made it also an object 

 to decide, by means of experiment and observation, whether the morbid 

 process, once develox-)ed, can be arrested by a simple medical treatment 

 — such a one as can be applied by the farmer — or not. Before I state 

 the results of my present investigation, it may be in order to first make 

 a few general statements, and to give the facts and observations upon 

 which those conclusions have been based, so as to enable the reader to 

 judge without bias, and to form an opinion of his own. I may also be 

 allowed to state that to obtain these facts and make these observations 

 I have visited twenty-five difierent herds of swine in different parts of 

 Henderson County, and several of them from four to eight times ; have 

 made fifteen post mortem examinations ; subjected to a special treatment 

 six different herds, namely, those of Messrs. Kennedy, Gilchrist, Eice, 

 Morris, Beaty, and Graham ; and have experimented on three healthy 

 pigs, specially procured for that purpose. It may further be stated that 

 the disease is, or was, prevailing this fall and winter, or from October 

 13 till the present, in a much milder form in Henderson County, a few 

 herds excepted, than it was last year at the corresponding season in the 

 counties of Champaign, Stevenson, Fulton, and Lee. At any rate, the 

 prevalence of the disease was not as general, its spreading was not as 

 rapid, and the mortality was not as great as during the same months 

 of last year in the counties named. The morbid process, too, in a ma- 

 jority of cases at least, was found to be limited almost entirely to the 

 organs of the chest (lungs, pleuras, and heart), and to the lymphatic 

 system ; w^hile last year serious morbid changes in the intestines, such 

 as ulcerous tumors in the caicum and colon, presented themselves in 

 about 75 per cent, of all the cases examined, in addition to the morbid 

 changes invariably found in the respiratory organs. This greater leni- 

 ency of the disease must, of course, be taken into consideration in judg- 

 ing the results of the experiments, and the effect of the measures of pre- 

 vention and of the medical treatment. 



Still, notwithstanding this greater leniency and the frequent absence 

 of conspicuous morbid changes in the intestines, numerous examinations 

 of living animals, fifteen post mortem examinations, and repeated micro- 

 scopic investigations have convinced me that the disease prevailing 

 this fall and v/inter among the swine in Henderson County is exactly 

 the same swine plague found last year in the counties of Champaign, 

 Stevenson, Fulton, and Lee, only this year's epizootic is milder, and the 

 digestive organs, but especially the colon and csecum, are less frequently 

 affected, which may account for the decreased malignancy or fewer 

 deaths and the slower spreading, because the infectious principle is 

 always the most concentrated, or, what is the same, the disease-produc- 

 ing germs, the Schizomycetes or bacillus germ.s, as I have called them 

 before (perhaps, erroneously, cf. below), are always the most numerous 

 in the excrements of animals in which the morbid process is x)rominently 

 developed in the intestinal canal. The duration of the disease in the 

 individual animals, or the time which elapses from the appearance of 

 the first symptoms tiU a termination, either in death or convalescence, 

 is reached, seems also to average a longer time this winter— in Hender- 

 son County at least — than last year at the other places named. Several 

 circumstances, undoubtedly, have combined to produce this result. Last 



