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BOVINE PATHOLOGY. 



CHAPTER I.— INTRODUCTION. 

 Section 1. 



Disease is a departure from a liealtliy condition, and is 

 consequently modified in its characters and effects in 

 animals of different species by special anatomical and 

 physiological peculiarities. In by far the larger number 

 of cases functional disorder is present, dependent on 

 structural changes, and it seems that, with the improve- 

 ments which will be made in our methods of minute 

 examination of tissues in health and in disease, we shall 

 in direct ratio find that diseases supposed to be purely 

 functional are due to alterations in structure. This has 

 already been done in many cases, and we may take it as a 

 law, sufficiently proved for working purposes, that disease 

 is a departure from healthy structure of constituents of 

 the body. These constituents of the body are elements, 

 such as cells, fibres, membranes, and granules, which are 

 combined together to form tissues, which produce by 

 union in various ways the organs which co-operate to 

 accomplish the various processes essential to life. In 

 the highest animals these organs are collected into 

 systems for the accomplishment of the various functions 

 which high complexity of vitality necessitates. Thus, 

 in pathology, we have to deal with_ elements, tissues, 

 organs, and systems, and all of these are bound together 

 so intimately in the animal mechanism, that alteration of 

 any one of them tends to throw the body into an abnor- 



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