DISEASE AMONG SWINE AND OTHER DOMESTIC ANIMALS. 35 



Intestinal worms are a very common occurrence in an omnivoi-ons animal like a hog, 

 but the same, if trachina spiralis and ci/sticercus ceUulosw (the well-known bladder- worm 

 of td'nia solium) are exce])ted, seldom canse very serions damage, provided the hog is 

 otherwise healthy, and is well kept and well fed. As to anthrax diseases, I do not 

 think they are very freqnent in the West ; at any rate, I have had no occasion to ob- 

 serve any of the various forms of anthrax plainly developed in swine since I have lived 

 in Kansas (nearly five years). Excluding anthrax diseases, and disorders caused by 

 intestinal worms, I have said tliat diseases (more than one) are called hog cholera, be- 

 cause the symptoms of disease, and especially the morbid changes found at the post- 

 mortem examinations, differ so much in ditfenmt patients as to make it impossible to 

 assign them all to one and the same disease. Still, as the morbid process is essentially 

 the same in every case, and the differences presented are mainly due to the fact that 

 the seat of the disease is sometimes in one organ, or set of organs, an<l sometimes in 

 another, the diseases may be considered as closely related to each other, and, from a 

 practical standpoint, it may be advisable to treat the same as members of one family, 

 or as different forms of one and the same morbid process. 



The nature of the diseases. — In a majority of cases the morbid process presents 

 itself as a catarrhal- rheumatic, and in others as a gastric-rheumatic, or bilious-rheu- 

 matic inHammation, and exhibits always, more or less plainly, a decidedly typhoid 

 character. As a catarrhal-rheumatic inflammation it has its principal seat in the mu- 

 cous membranes of the respiratory passages, in the substance of the lungs, in the pul- 

 monal plenra, or serous membrane coating the external surface of the lobes of the lungs, 

 in the costal pleura, or serous lining of the internal surface of the chest, in the dia- 

 phragm, and in the pericardium or serous sac inclosing the heart. As a gastric-rheu- 

 matic inflammation the principal seat of the disease is found in the abdominal cavity, 

 but especially in the liver, in the spleen, in the large and small intestines, in the kid- 

 neys and ureters, and in the peritoneum or serous membrane lining the interior surface 

 of the abdominal cavity, and constituting the external coat of most of the organs sit- 

 uated in that part of the body. The name of " hog cholera," therefore, as has been said 

 before, is, in more than one respect, an ill-chosen one. It should be abolished at once, 

 and a more appropriate one should take its place. As such an one I have proposed 

 "Epizootic influenza of swine," for two reasons : 



First, the disease bears, in all its morbid features, and especially in the diversity of 

 its forms, produced by the differences of the parts or organs which in different animals 

 become the seat of the morbid process, a striking resemblance to the yet well-remem- 

 bered epizootic influenza of horses, which, a few years ago, swept the whole country 

 from the Atlantic to the Pacific. Still I do not wish to be understood as saying that 

 the epizootic influenza of swine is identical with the epizootic influenza of horses. 

 The resemblance, besides the epizootic spreading and the typhoid character, is limited 

 to the symptoms and to the morbid changes. An important difference is presented by 

 the greater malignancy of the disease of swine. 



Secondly, a name derived from a consjiicuous or characteristic symptom, or from an 

 important and constant morbid change — pleuro-pneumonia of swine, for instance — 

 might be more convenient if the main seat of the morbid process were always in the 

 lungs and the pleura, or invariably the same in every patient; but, as the seat of the 

 disease is not limited to the respiratory apparatus, but is also frequently formed in the 

 parts and organs situated in the abdominal cavity, and sometimes even in the centers 

 of the nervous system, a name should be chosen comprehensive enough to cover all the 

 different forms in which the disease is able to make its appearance, and, at the same 

 time, snfBcieutly distinct to prevent diagnostic confusion. Epizootic influenza of swine 

 will, I think, answer the purpose. 



Symptoms and morbid changes. — As the morbid process has its seat in various 

 parts or organs of the animal body, the disease presents itself in different forms and 

 manifests itself by different symptoms, so that, at any rate, besides other complica- 

 tions, two principal and two subordinate forms or varieties must be discriminated. 



1. The catarrhal-rheumatic form. — Thisis the most frequent of the two principal 

 forms. The morbid process has its main seat in the respiratory organs ; the disease 

 presents the features of a respiratory disorder, and either the catarrhal or the rheu- 

 matic character predominates, or both are equally develojied. If the latter is the case, 

 the whole respiratory apparatus may be found diseased. If the catarrhal character is 

 the one most developed, the principal seat of the disease will be found in the larynx, 

 in the windpipe, in the bronchial tubes, and, to a greater or less extent, in the sub- 

 stance of the lungs. If the rheumatic form is the predominating one, the principal 

 morbid changes occur in the serous membranes of the chest (the costal and pulmonal 

 pleura and the pericardium), and also to some extent in the tissue of the lungs. In 

 most cases, however, the catarrhal and rheumatic character are blended with each 

 other, and the respiratory passages, the tissue of the lungs, and the serous membranes, 

 or portions of them, are more or less diseased. Animals affected with the catarrhal- 

 rheumatic form indicate the presence of the disease by a short and more or less hack- 

 irg cough— generally one of the first symptoms— by difficulty of breathing,Ja parting 



