144 DISEASES OF SWINE 



The color of the kidney is usually darker than normal, being 

 often very dark, almost chocolate in color. When we pick the 

 kidney up in the hand and examine it, we also find that it is much 

 softer than the normal healthy kidney, which is quite firm. When 

 we look at the organ closely we are immediately attracted by a 

 very pecuhar and characteristic pathologic finding. This consists 

 in the appearance on the surface of the organ of a number of small 

 pin-head-like spots of a reddish color. These shine through the 

 serous covering or capsule of the kidney and give a very typical 

 appearance. These spots may be very few in number and require 

 careful search to demonstrate them, while in other cases, especially 

 those of the acute type, we may find the organ literally riddled with 

 these spots, giving an appearance not unUke that of a turkey egg. 



If you take the knife and strip off the capsule of the kidney, and 

 wash the surface in clear water, it will make these spots stand out 

 much more plainly and make them very evident. As to color, 

 they vary from a bright red dot to a dark colored, almost black, 

 spot. They are found all over the outer surface of the kidney, and 

 we will find when we cut into the organ that they are also Uberally 

 sprinkled on its inner surface. 



These spots are small pin-point hemorrhages, which are de- 

 signated, pathologically, as petechial hemorrhages. They are 

 in every respect the same as the petechial hemorrhages which 

 were described under the head of Skin Lesions. They are very 

 typical in appearance and once seen will never be forgotten. 



These petechial hemorrhages are formed in the following 

 manner: The blood-vessels of the kidney are very small in size, 

 especially the vessels in the outer two-fifths or cortex of the 

 organ. On account of their small size these vessels are very easily 

 stopped up, and when the virus of cholera circulating in the blood 

 reaches the kidneys it collects in these small capillary vessels and 

 results in their occlusion or stoppage. As a result, there is a 

 stretching and rupture of the dehcate vessel wall and blood escapes 

 into the substance of the kidney. These small spots on the sur- 

 face are merely the reflection shining through of these cortical 

 hemorrhages in the substance of the kidney. 



When we take the knife and cut into the kidney, we find 

 that the organ is much softer than normal, and cuts very much 



