286 SWINE PRACTICE 



cough, dyspnea, nasal and ocular discharge, cutaneous erythema, 

 tumefactions and necrosis. 



Diagnosis. — From the foregoing description of the lesions and symp- 

 toms of hog cholera it will be evident that the diagnosis is difficult. 

 There are some laymen and an occasional veterinarian who diagnose 

 all ailments of swine as hog cholera. Recent recognition of some other 

 infections of swine have caused confusion to clinicians, and the identi- 

 fication of hog cholera has apparently become more difficult. 



The symptoms evidenced may be suggestive of hog cholera, but a 

 diagnosis should not be based upon symptoms alone. The lesions 

 found in swine dead of cholera, excepting cloudy swelling, are not 

 constant and uniform, but nevertheless are of value in arriving at a 

 diagnosis. Hyperemia and hemorrhages in the submucosa, subserosa 

 and lymph-glands, although they may be due to some associated con- 

 dition are quite common and serve as a guide in diagnosis. The 

 hemorrhages in the submucosa of the bladder and epiglottis, although 

 not always present in cases of hog cholera, are considered when pres- 

 ent as characteristic by many investigators. It is very probable that 

 similar hemorrhages may be observed in cases of hemorrhagic sep- 

 ticemia. The so-called "turkey-egg kidney" is not characteristic of 

 hog cholera, as this lesion occurs in hemorrhage septicemia and prob- 

 ably some other infections; however, this lesion may be observed in 

 the carcasses of swine that have died of hog cholera. 



Pneumonic lesions are relatively common in hog cholera. The lesion 

 in the lung consists of croupous pneumonia and involves the cardiac 

 or cephalic lobes. This lesion cannot be considered characteristic of 

 hog cholera, as it is the typical lesion of croupous pneumonia. 



Swine plague is distinguished from the pectoral form of cholera 

 by the fact that the former is characterized by catarrhal pneumonia 

 in the early stages of the disease, and by necrotic pneumonia in the 

 later stages, and also by the presence of fibrinous pleurisy with or 

 without adhesions. 



Engorgement of the spleen is a common lesion in acute cholera, but 

 this condition sometimes occurs as a result of disturbed digestion and 

 as a result of leukemia, and is a common lesion of other septicemic 

 diseases. Therefore enlarged spleen alone should not be considered 

 a sufficient evidence upon which to base a diagnosis of cholera. 



The congestion and hemorrhage of the lymph nodes is one of the 

 most common lesions of cholera, but this lesion is not always present. 

 Hemorrhages of the suberosa and submucosa are quite constant in 



