254 



HOG CHOLERA 



post-mortem examination and even the diagnosis must often 

 be delayed until the results of a bacteriological examination 



have been obtained. It not infre- 

 quently happens that swine suffering 

 from hog cholera are attacked with 

 swine plague, the two diseases co- 

 existing in the same animal. 



§ 184. Morbid anatomy. The 

 acute type. This might with equal 

 propriety be called the hemorrhagic or 

 septicemic type, inasmuch as the chief 

 and perhaps the only obvious changes 

 are hemorrhagic in nature. They are 

 more conspicuous when an animal is 

 examined immediately after death. 

 The spleen is variably enlarged, soft, 

 and gorged with blood. Sometimes 

 it is twice as long as normal and the 

 other dimensions are proportionately 

 increased. It may extend across the 

 median line to the right side. Next 

 to the spleen, the lymphatic glands 

 \ and the serous membranes are most 

 K/V' severely involved. The cortex of the 

 glands appears on section as a hemor- 

 rhagic line or band, according to the 

 amount of extravasated blood, or the 

 entire gland may be infiltrated with it. 

 Among the glands most commonly 

 hemorrhagic are those of the meso- 

 colon, those at the root of the lungs, 

 and on the posterior thoracic aorta. 

 Besides these, the retro-peritoneal and 

 the gastric glands ma}' be involved. 

 More rarely the mesenteric glands show slight blood extrava- 

 sations. Hemorrhages are also quite frequent beneath the 

 serous surfaces of the abdomen and thorax. They are most 



Fig. 60. Ulcers in tlie in- 

 testine of a pig dead of 

 hog cholera. 



