BACILLUS ABORTUS (BANG) AS AN ETIOLOGICAL 

 FACTOR IN INFECTIOUS ABORTION IN SWINE 



EDWIN S. GOOD and WALLACE V. SMITH 



From the Laboratory of the Department of Animal Husbandry, Kentucky Agricul- 

 tural Experiment Station, Lexington, Kentucky 



So far as we are able to learn from the literature, the cause 

 of infectious abortion in swine has never been determined. Lynch 

 in his "Diseases of Swine," says, "Infectious abortion results 

 from the infection of the genital passages by some specific germ, 

 the true nature of which is as yet undetermined. The disease 

 is not nearly so common as in mares and cows, and, while it may 

 run through an entire herd, it is not likely to be spread from 

 one farm to another except in unusual instances." He fur- 

 ther states, "The infectious type of the disease is especially 

 mild in its sjonptoms, and unless the animals are carefully 

 watched the pigs may be slipped without any notice of the fact 

 until several weeks later, when it is found that the sow is no 

 longer pregnant." He also says, "The nearer to full term the 

 sow is at the time of abortion, the less dangerous the occurrence 

 and the more mild the symptoms. Signs of threatening abortion 

 are loss of appetite, restlessness, making of the bed, shivering, 

 trembling of the muscles, dulness, and in some cases very severe 

 labor-pains." 



While considerable work has been done with regard to in- 

 fectious abortion in mares and cows in this laboratory, only 

 three outbreaks of infectious abortion among sows, have come 

 to our investigation. We have found that it is no uncommon 

 occurrence for one or two sows in a herd to abort. Numerous 

 cases of this kind have been studied by the writers, with no 

 etiological results, which would lead to the opinion that such 

 abortions were due to some accident. 



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