Asthma. Broken Wind. Heaves. Dyspnoea, Etc. 369 



filled with hay, horses will eat from thirty to thirty-five pounds of 

 this daily and many become brokenwinded. The breeding mares 

 which get little hay, seldom become affected though the plentitude 

 of their abdomen and the impaired respiratory function might be 

 thought to conduce to the affection. 



The leafy leguminous plants are slow to dry and as hay are 

 always charged with cryptogams and bacteria and their products, 

 which are manifestly a potent factor in causing heaves. 



In England broken wind is much less prevalent than on the 

 European Continent and it is deserving of notice that lucerne and 

 sainfoin hold no place among the British green crops, that red 

 clover hay is only exceptionally met with owing to the amount of 

 land that is clover-sick, that natural hay is largely used, and that 

 when horses are largely fed on hay it is qualified by such laxative 

 agents as turnips, carrots, beet, etc. 



All this throws light on the immunity of horses on our western 

 prairies and plains. Feeding on the indigenous grasses fresh or 

 made into hay, they are saved from the noxious influence of those 

 artificial products which are found in all countries to determine 

 the development of broken wind. It needs not that we adopt 

 the popular notion that any special plant growing in these pas- 

 tures ensures the safety of the equine races. It is merely a repe- 

 tition in the Western Hemisphere of the experience so long before 

 obtained in the case of Spain. Parallel with the progress of cul- 

 tivation in our western lands, we see this malady advancing. 

 Fifty years ago it was virtually unknown in Michigan and adja- 

 cent states, whereas now, these states can almost emulate New 

 York in the relative number of their victims. It must not, how- 

 ever, be supposed that this cultivated fodder is the sole cause of 

 the westward march of this malady. With improved agriculture 

 have come better roads, spring wagons, and driving at a pace 

 which was comparatively unknown to the early settlers. 



In California the condition of Spain was for long pretty accur- 

 ately repeated. With no winter worthy of the name, troops of 

 horses were left at pasture throughout the whole year and those 

 that were stabled subsisted chiefly on natural hay in which the 

 indigenous grasses were commingled with white — but no red — 

 clover. California long retained the reputation of having no 

 broken-winded horses. 

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