PREFACE TO THE FIRST EDITION 



The literature on infection and the etiology and morbid 

 anatom}^ of infectious diseases of animals is exceedingly rich 

 in the results of new discoveries and important investigations. 

 However, students just beginning this study and following a 

 prescribed curriculum have not the time nor are they prepared 

 to read with profit the detailed records of original research. 

 Such publications seem to be better adapted for those doing 

 advanced or graduate work. Furthermore many of these 

 publications are out of print and are only available for con- 

 sultation. For these reasons it is believed that a volume con- 

 taining the rudiments of the subject will be of use to the stu- 

 dent and an aid to the teacher. It is also believed that such 

 a work will be of assistance to practitioners. 



In preparing this volume the aim has been to bring to- 

 gether in a concise form the fundamental facts in the path- 

 ology of the more common infectious diseases of animals, 

 especially those existing in the United States, with which 

 sanitarians and the practitioners of comparative medicine must 

 contend. To tins end the current literature, the reports of 

 the investigations made at various Institutions and Experi- 

 ment Stations, as well as the standard works on comparative 

 pathology have been freely drawn upon, to all of which full 

 acknowledgment is hereby made. 



In order to bring into consideration the clinical value of a 

 knowledge of morbid anatomy a few of the symptoms or ante- 

 mortem manifestations have been included. It is hoped that 

 this correlation of symptoms and lesions will stimulate a deeper 

 interest in the stud}- of comparative pathology and thus render 

 it of more permanent and practical value for those entering 

 into the practice of veterinary medicine. 



In selecting the subject matter care has been taken to 

 avoid, as far as possible, the introduction of results concerning 



