320 STATE BOARD OF AGRICULTURE. 



Contaminated food and ivater. Food or water soiled by the discharges 

 of an animal that has aborted or of an atl'ected animal that has calved 

 normally may convey the disease to a healthy animal. Calves born of 

 such animals may also spread the disease germs with their feces. 



DIAGNOSIS. 



Infectious and non-infedtious. As to the diagnosis of infectious abor- 

 tion it may be said that not all abortions are known to be infectious. 

 Various causes may produce abortion. It is of the utmost importance, 

 when an animal aborts to determine if possible whether the abortion is in- 

 fectious. There are no symptoms by which this fact can be determined 

 with accuracy although the history of the case may be helpful in mak- 

 ing a diagnosis. 



Blood tests. Through a blood examination the nature of the abortion 

 or the presence of infection in the herd may be determined with a fair 

 degree of accuracy. We shall be glad to make this examination without 

 cost for anyone who will furnish us with about one ounce of blood from 

 each animal to be examined. When abortion occurs in a herd it is sug- 

 gested that every animal in the herd be tested. It is a fairly easy opera- 

 tion to draw the blood from the jugular vein. Any qualified veterina- 

 rian, with about two men to assist in holding the animals should be able 

 to draw 20 to 30 samples in an hour. This laboratory will furnish sterile 

 bottles for the samples to anyone requesting them and stating the num- 

 ber to be tested. 



Limitations of hlood tests. Let it be understood that we cannot de- 

 termine by this test whether an animal will abort. Not all affected 

 animals will abort. Abortion is a symptom of a disease and like most 

 symptoms is not constant. The test may serve to determine the extent 

 of infection in a herd but not the number of animals that will abort. 

 The test indicates that an animal may harbor the infection for years 

 without aborting. If this is true it may be necessary to handle such 

 an animal with the same care to prevent spreading of the disease as 

 though abortion had occurred. 



Sterility. One of the serious aspects of this disease is the frequency 

 with which sterility follows abortion. If we can prevent this by local 

 treatment of the genital organs, following pregnancies will, in the ma- 

 jority of cases, terminate normally. 



Carriers. We have reason to believe that an animal may harbor the 

 infection for years and, while able to tolerate the presence of the abor- 

 tion germ, she may be a constant menace to susceptible animals in the 

 herd. Again there are animals in affected herds that become infected 

 but may. not abort. Such animals, and those that have apparently re- 

 covered, since they do not continue to abort, are to be considered dan- 

 gerous animals in the herd from a sanitary point of view, and ones pre- 

 senting great difficulties in the control of the disease. In carrying out 

 any plan aimed at the eradication of the disease, such animals should be 

 handled in a manner similar to that em]»loyed with aborting animals. 



