TREATMENT. 81 



In the vast majority of the former cases the animals so affected 

 are unfit for even a moderate amount of work. Effusion into 

 the cavity or sac of the pericardium, hydropericardium, with 

 thickening of its texture from organization of the effusion 

 resulting from the inflammatory action, are the chief 

 changes obviously resulting from an attack of influenza, in 

 which the covering of the heart immediately participates. 



In connection with the heart itself, we may have defective 

 muscular contractility, the result of certain peculiar changes 

 which have occurred in the intimate structure of the muscular 

 fibres ; or there may be thrombi in the great cavities, and 

 stretching into the large bloodvessels ; or more frequently 

 there exists a diseased condition consisting in deposition, 

 thickening, or adventitious growth of a fibrous or warty 

 character on the valves of the heart, by which their perfect 

 efficiency is interfered with and materially lessened. 



These cardiac lesions again are, as a rule, the fruitful and 

 immediate cause of local dropsical swellings over the inferior 

 parts of the body and of the limbs. 



When thickening of the tendons or tendinous sheaths of the 

 great flexor muscles of the limbs remain as the effect of an 

 attack of this fever, the usefulness of the animal may be im- 

 paired for a lengthened period, or permanently destroyed.. 



Besides these, but of less frequent occurrence, and always 

 of a doubtful and dangerous character, are certain peculiar 

 renal disturbances, consequent upon blood-changes and con- 

 taminations. 



