Investigations Concerning the Horse. 273 



429. Mare's milk. The following table presents the composi- 

 tion of mare's milk, with cow's milk for comparison, according 

 to Konig: 1 



Percentage composition of mare's milk; cow's milk being given for 

 comparison Konig. 



It is shown that mare's milk contains more water than that of 

 the cow, the casein, albumen, fat and ash being about one-half 

 that found in cow's milk, while the sugar is nearly one per cent, 

 higher. If cow's milk is used for feeding foals, it should be 

 diluted with water and sugar added. 



The quantity of milk yielded by mares has been determined in 

 only a few cases. According to Goltz, 2 Tartarian mares produce 

 from 450 to 500 pounds of milk per year in addition to that 

 required by their foals. Such mares remain in milk two years. 



Vieth 3 reports that good milking mares on the steppes of south- 

 eastern Russia yield from 4 to 5 liters (quarts) of milk daily when 

 milked five times a day, as is the practice. 



II. Wolff's Studies of Feed Consumed and Work Performed, by the 



Horse. 



430. Plan of investigation. Wolff's feeding and digestion ex- 

 periments with the horse are the first extensive and systematic 

 efforts in this line. From the necessities of the case his work 

 was done with single animals. He first studied the comparative 

 digestibility of various feeding stuffs with the horse, and later 

 the relation of feed consumed to the amount of work performed. 

 To discuss the results of these investigations intelligently it is 

 necessary to first consider the method adopted for measuring the 

 work done by the horse. 



1 Clieiu. cl. MeiiRch. Nahr. u. Genus-mitteL 



2 Lamlw. Ill, p. 520. 



8 Ld\v. Vers. iSta. 31 (1885), p. 354. 

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