86 SWINE DISEASES 



white blood cells, some of which are disintegrated. Large 

 quantities of this defibrinated blood, containing cor- 

 puscles in various stages of disintegration as well as the 

 virus, are introduced into an ear vein. The first capillary 

 system it would pass through is in the lung where, no 

 doubt, more or less obstruction of capillaries is effected 

 and the virus, or some chemical ingredient of the blood, 

 may cause an increased permeability of the blood vessels 

 and facilitate the outpouring of the serum. 



Lesion. The lungs are engorged with blood. The 

 air cells contain varying quantities of serum, the lung 

 thus becoming soggy and edematous. No other lesion 

 of any significance is found. 



Symptoms. The affected animal at first becomes 

 restless and uneasy. There is increased respiration, 

 soon followed by dyspnea, cessation of breathing, and 

 death. In some cases all these symptoms occur within 

 a few minutes and during the time that the virus is being 

 introduced. If the injection is stopped instantly when 

 the first symptom becomes evident some of the affected 

 swine will recover, but in some of them the various 

 symptoms occur, succeeded by death, even though the 

 introduction of virus be stopped when the first symptom 

 appears. An occasional case occurs where the swine 

 will show no discomfiture at the time of the injection of 

 the virus, but may be found in distress from a few minutes 

 to an hour later. In such cases, death will usually 

 result. 



Treatment. Thus far no treatment has been found 

 that appears to be of value. It is possible that centri- 

 fuging the virus will overcome the difficulty. 



Hemorrhage 



Pulmonary hemorrhage is not common in swine as 

 a primary disease. It has been reported as occurring in 

 fattened swine that are driven to market, especially 

 when they become very hot. It is rather common as a 

 secondary condition in acute cases of pneumonia, swine 

 plague, and hog cholera. 



