Contagious Abortion. 149 



Infection of the animal. There are many ways in 

 which the causal organisms may be carried from the in- 

 fected animal to a healthy one, as by direct contact, soiled 

 bedding, the attendants, etc. A less direct way is by the 

 bull that has served infected animals and later has been 

 used with healthy cows. The bull is one of the means 

 of introducing the disease into the herd, either through 

 purchase or by the use of the bull of the herd on in- 

 fected cows or by patronizing bulls kept for public ser- 

 vice. 



Prevention. Attention should be directed to the con- 

 dition of the herd from which each animal is purchased. 

 If it is not certain that the herd is free from the disease, 

 it may be well to keep the purchased animals apart from 

 the herd until after calving at full time has occurred. 

 In order to prevent the spread of the disease in the herd 

 attention must be directed toward the destruction of all 

 material that may contain the organisms. To accom- 

 plish this, the fetus and after-birth should be destroyed, 

 preferably by burning. The aborting animal should be 

 removed from the herd, the stable disinfected and all 

 cows that may have been exposed also disinfected. The 

 animal should be given vaginal douches with some disin- 

 fecting solution such as one ounce of tincture of iodine 

 in one ounce of glycerine, the mixture being added to one 

 gallon of warm water. The external genitals, hind quar- 

 ters, and tail should be washed with a one to one thou- 

 sand solution of corrosive sublimate. The douches and 

 external treatment should be repeated several times and 

 the animal should not be returned to the herd as long as 

 there is any vaginal discharge. 



All pregnant cows of the herd should be treated by 

 washing the external genital parts with corrosive subli- 



