162 



Biological Therapy 



this purpose two cubic centimeters should be injected sub- 

 cutaneously a few days before parturition, the same amount 

 at the time of and again a few days subsequent to parturi- 

 tion. In cases in which symptoms are not entirely pre- 

 vented by this treatment it has been observed that treated 

 animals respond to subsequent treatment much more read- 

 ily than the untreated, and that the symptoms are much less 

 acute. 



Mixed Infection in Swine 



This condition so frequently diagnosed in swine, does 

 not exist as an entity but is usually the coexistence of 

 hemorrhagic septicemia and necrotic enteritis in the same 

 individual. For that reason it is advised that the treatments 

 and preventive measures described under necrotic enteritis 

 be applied to this condition. 



Necrotic Enteritis 



This is a condition affecting swine and characterized by 

 progressive emaciation following congestion, thickening and 

 necrosis of the intestinal mucosa. In certain sections of the 

 country it is extremely prevalent and occasions great losses. 



ETIOLOGY. The exact cause of this disease is not 

 known. It is believed that the condition may be brought 

 about by any of several different bacteria which are nor- 

 mally present in the intestinal tract and which assume in- 

 creased virulence after some devitalizing condition has low- 

 ered the resistance of the affected animals. The organisms 

 most frequently isolated from necrotic enteritis are B. para- 

 typhosus b., B. suipestifer, B. coli and B. suisepticum. The 

 disease is known to be extremely prevalent following hemor- 

 rhagic septicemia, hog cholera or parasitic infestations. 

 While other devitalizing conditions may precede necrotic 

 enteritis, the disease most frequently follows those men- 

 tioned above. 



SYMPTOMS. Necrotic Enteritis is most frequently ob- 

 served as a chronic affection characterized by great emacia- 

 tion, an arched back, unthrifty coat and tough leathery skin. 

 The gradual and progressive loss of flesh causes the animal 

 to become greatly emaciated resulting in this disease being 

 referred to as "Drying up Disease." 



