134 SWINE PEACTICE 



although the colon bacilli and its various derivatives have been identi 

 tied in the pus from liver abscesses. 



Lesions. — The liver contains suppurative centers of varying di- 

 mensions. The foci may occur throughout the entire liver and be 

 microscopic in size, causing a uniform enlargement of the liver, or 

 the suppurative centers may be as large as walnuts and appear as 

 small abscesses. The liver will be engorged with blood, more friable 

 than normal, and it may be variegated in color, due to alternating 

 small hemorrhagic areas and suppurative foci. 



Larger suppurative centers are gray in color and may or may not 

 be circumscribed by a capsule of fibrous tissue. The content may 

 be semifluid pus or it may be caseous or even calcified. 



Symptofms. — The evidence of suppurative hepatitis consists of gen- 

 eral depression. The animal does not move of its own volition. There 

 is pain on palpation of the abdomen (if abdominal walls are not too 

 thick), and icterus. Less extensive suppuration of the liver may not 

 produce any distinct symptoms. 



Treatment. — The animal should be made as comfortable as possible 

 and the evacuation of the bowel content facilitated by the use of 

 laxatives. ' 



A type of hepatitis associated with a perilobular eosinophylic 

 infiltration has been observed. These cases are of rather common 

 occurrence in meat inspection but apparently are of little signifi- 

 cance clinically, at least we are unable to find any reports of cases 

 from practitioners. The cause of eosinophylic infiltration into the 

 liver has not been determined but it is probably associated with para- 

 sitic invasion, perhaps more particularly with the migration of the 

 larval form of parasites such as the ascarids. 



Affected livers are enlarged and contain small grayish white 

 centers. On microscopic examination the white centers are found 

 to be masses of eosinophylic leucocytes. Local invasions of eosino- 

 philes have been observed in other tissues and appear to depend 

 upon the motility of the eosinophiles, although technicians claim 

 that these cells are not motile. Chemic substances derived from 

 parasites may produce an activity of the eosinophiles or may 

 stimulate these cells to multiply in the field of action. The phe- 

 nomenon is certainly the response of some abnormal stimulus and 

 in a general way is parallel to the neutrophylic, polymorphic, leucocy- 

 tic migration toward a suppurating center. 



