480 



DISEASES OF THE CIRCULATORY SYSTEM. 



is nearly normal ; in aortic contraction, on the contrary, it is very 

 small and at times slower. 



2. A diastolic bruit (blowing) may be derived from a mitral or 

 tricuspid contraction, from an aortic or pulmonary insufficiency/ 

 The latter is extremely rare. Tricuspid contraction, which is fre- 

 quent in the ox, is accompanied by venous pulse and dyspnœa, 

 phenomena which are consecutive to the formation of thrombosis 

 in the right heart. In mitral contraction the Dulse is small and 

 irregular ; in aortic insufficiency it is strong and rapid. 



Treatment of valvular diseases. As long as valvular affec- 

 tions are compensated, they do not require any treatment. We 

 may be limited to good feeding of the animals, avoiding excitement 

 -and violent exertions. 



But as soon as we observe symptoms of heart exhaustion, respi- 

 ratory troubles, venous stagnation, we must resort to certain means 

 which regulate and diminish the circulation, increase the blood 

 pressure in the arterial system, and give to the myocardium the 

 necessary time for its rest and nutrition. In this respect, digitalis 

 constitutes a valuable medicament ; it increases arterial pressure, 

 diminishes the pulse, and compensates the circulatory troubles. If 

 îised in the form of powder or infusion of 1 to 2 grammes, it is 

 proper to give it at intervals, for several days consecutively, watch- 

 ing attentively the effects produced. Large doses should be avoided : 

 for the dog, we may use an infusion of 1 to 2 grammes of digitalis 

 leaves in 250 grammes of water (one to two tablespoon fuis per day; 

 one to two teaspoonfuls for smaller animals); for large animals, we 

 •generally use the powder given upon bread or in the shape of elec- 

 tuary ; dose for the horse, 2 to 5 grammes ; for the ox, 4 to 8 

 grammes. Tincture and extract must be abandoned on account of 

 the uncertainty of their containing digitalin. When dropsies exist, 

 caffeine is advisable, its diuretic properties are more evident than 

 those of digitalis and it is less toxic than the latter, especially when 

 we are obliged to prolong its administration ; it is given in the shape 

 of sodo-benzoate of caffeine in a dose of 1 gramme for the dog, 5 to 

 10 grammes for the horse and ox. The tincture acts in a similar 

 way (horse and ox, 10 to 25 grammes ; dog, 10 to 25 drops). 



1 In our animals, the diastolic blowing is, in almost all cases, the expression of an 

 aortic insufficiency. The blowing produced by the contraction of one of the auriculo- 

 ventricular openings (rare) is only heard toward the end of the great pause, when the 

 corresponding hypertrophied auricle drives the last portion of the blood which it con- 

 tained through the contracted orifice ; it is presystolic. — n. d. t. 



