74 DISEASES OF CATTLE. 



often involved in inflammation arising from the absorption of 

 deleterious matter. 



Absorption is the function of the lymphatics. The liquor san- 

 guinis passes from the blood capillaries to supply nutrition to the 

 tissues. All of the liquor sanguinis that is not required is absorbed 

 by the lymphatic vessels and conveyed back to the blood by the h'm- 

 phatic ducts. The lymphatics which proceed from the intestines 

 convey the chyle into the blood during digestion. As a rule, the 

 lymphatic vessels follow the course of the veins. All the absorbent 

 vessels convey their contents to the thoracic duct and right great 

 lymphatic vein, which empty into the anterior vena cava, where 

 the lymph and chyle mix with the venous blood, and thus maintain 

 the supply of nutritive elements in the blood. 



THE PULSE. 



As fully explained, the heart pumps the blood throughout the 

 arterial system. The arteries are always full and each contraction of 

 the ventricle pumps more blood into them ; this distends their elastic 

 walls and sends along them a wave which graduall}^ becomes less 

 perceptible as it nears the very small arteries. This wave constitutes 

 the pulse, and is lost before the capillaries are reached. The sen- 

 sation or impression given to the finger when placed upon the artery 

 shows the force exerted by the heart and some important facts con- 

 cerning the condition of the circulation. In adult cattle the average 

 number of pulsations in a minute is from 50 to 60. The pulse is 

 faster than normal after exercise, excitement, on hot days, from 

 pain, and as a result of fullness of the stomach. In old animals it is 

 slower than in the young and in males slightly slower than in 

 females. In fevers and inflammations and in local diseases of the 

 heart the pulse rate is increased. If the rate is greater than 100 or 

 110 to the minute the outlook for recovery is not good. 



Other variations of the pulse are known as infrequent pulse, which 

 means that the number of pulsations in a given time is less than nor- 

 mal. The irregular or the intermittent pulse is when the pulsations 

 do not follow in regular order. The large pulse and the small pulse 

 refer to the volume of the pulse, which may be larger or smaller 

 than usual. The strong pulse and the feeble pulse refer to the 

 strength or weakness of the pulsation. The pulse is said to be hard 

 when the vessel feels hard and incompressible, the soft pulse being 

 the opposite. By dicrotic pulse is meant that kind of pulsation 

 Avhich makes each beat seem double, and therefore it is generally 

 called the double pulse. 



The venous or "jugular pulse" is the pulsation so frequently 

 observed in the jugular vein of cattle and is particularly noticeable 

 while they are ruminating — ^" chewing the cud." It is not always 



