DISEASES FOLLOWING PARTURITION. 247 



MILK FEVER PARTURITION FEVER PARTURIENT APOPLEXY PAR- 

 TURIENT COLLAPSE. 



This disease is not only peculiar to the cow, but it may be said to be 

 virtually confined to the improved and plethoric cow. It further occurs 

 only at or near the time of calving. Indeed, these two factors, calving 

 and plethora, may be set apart as preeminently the causes of this dis- 

 ease. It is the disease of cows that have been improved in the direc- 

 tion of early maturity, power of rapid fattening, or a heavy yield of 

 milk, and hence it is characteristic of those having great appetites and 

 extraordinary power of digestion. The heavy milking breeds are espe- 

 cially its victims, as in these the demand for the daily yield of 50 to 100 

 pounds of milk means even more than a daily increase of 2 to 3 pounds of 

 body weight, mainly fat. The victims are not always fat when attacked, 

 but they are cows having enormous powers of digestion, and which 

 have been fed heavily at the time. Hence the stall-fed city dairy cow, 

 and the farm cow on a rich clover pasture in June or July, are espe- 

 cially subject. The condition of the blood globules in the suffering cow 

 attest the extreme richness and density of the blood, yet this peculiar- 

 ity appears to have entirely escaped the notice of veterinary writers. 

 1 have never examined the blood of a victim of this disease without find- 

 ing the red blood- globules reduced to little more than one-half their 

 usual size. Now, these globules expand or contract according to the 

 density of the liquid in which they float. If we dilute the blood with 

 water they will expand until they burst, whereas if solids, such as salt 

 (ii albumen, arc added they shrink to a large extent. Their small size, 

 therefore, in parturition fever indicates the extreme richness of the 

 blood, or, in other words, plethora. 



Confinement in the stall is an accessory cause, partly because stabled 

 cattle are highly fed, partly because the air is hotter and fouler, and 

 partly because there is no expenditure by exercise of the rich products 

 of digestion. 



High temperature is conducive to the malady, though the extreme 

 colds of winter are no protection against it. Heat, however, conduces 

 to fever, and fever means lessened secretion, which means a plethoric 

 Stan- of the circulation. The heats of summer are, however, often only 

 a coincidence of the real cause, the mature rich pastures and especially 

 the clover ones being the greater. 



Electrical disturbance* have an influence of a .similar kind, disturbing 

 the functions of the taxly, and favoring sudden variations in the circula- 

 tion. A succei< in of cases of the malady often accompany or precede 

 a change of weather from dry to wet, from a low to a high barometric 

 preMure. 



Cotircnex9, which is the usual concomitant of fever, may in a case of 

 this kind lu'come an accessory cause, the retention in the blond of what 

 should liave passed oil' by the t>n\vc)s tending to increase the fulness of 

 the blood vessels ami the density of the blood. 



