Preface ix 



The new-born animal can be studied freely regarding the 

 infections carried from the uterus, can be fed experimen- 

 tally, and may be destroyed at will for examination. If the 

 veterinary profession is fully to live up to its opportunities 

 and discharge its obligations to the state, it must contribute 

 its share to the advancement of the knowledge of disease. 

 Nowhere else can it contribute more, nor as much, of value, 

 as in the basic principles of the physiology, pathology and 

 hygiene of reproduction. 



Purely a clinician, I have been dependent upon others for 

 bacteriologic and histologic facts. In this field Drs. W. A. 

 Hagan and C. M. Carpenter have rendered invaluable 

 aid. Working first in my department and later in the de- 

 partment of pathology and bacteriology, they have extended 

 every possible assistance. Similar help has been given by 

 Dr. Herbert L. Gilman, at present in my department. The 

 reader should undertsand the difficulty of securing knowl- 

 edge regarding genital infections in animals. In general 

 bacteriologists have not studied the genitalia of animals for 

 infections, but for one specific infection, and have left un- 

 recorded and unstudied all others. If the bacillus thought 

 by the investigator to be the cause of infectious abortion was 

 recognized, that was deemed final proof of it, and no other, 

 caused the disease. Drs. Hagan, Carpenter, and Gilman 

 have so far as practicable studied all bacteria found in the 

 genital organs and their significance in the problem of re- 

 production. 



My collaborator, Dr. W. W. Williams, has contributed 

 greatly to the value of the treatise. Having devoted his en- 

 tire energy for a number of years to the handling of genital 

 diseases and the advancement of reproductive efficiency in 

 purebred cattle, he has demonstrated with unusual clearness 

 the value of the scientific handling of this group of infec- 

 tions. He has contributed especially the sections upon the 

 surgery of the cervix and the genital infections of bulls. 



W. L. Williams. 

 Cornell University 

 Ithaca, N. Y. 

 April, 1921 



