182 THE CHEMISTRY OF THE FARM 



been carefully determined by Zuntz. A borse of 

 1,100 lbs. live weigbt will require food supplying 

 12,100 Calories per day, equivalent to about 7 lbs. of 

 digestible starch. Owing to the great consumption 

 of energy during the digestion of fibrous foods by the 

 horse, already referred to (pp. 121, 126), fibre can be used 

 to only a limited extent in the rations. Zuntz found 

 that for a successfal maintenance diet, at least one- 

 third of the energy of the food must remain over for 

 use in the animal body after all the energy demanded 

 by the work of digestion had been expended. A refer- 

 ence to the table on p. 122 will show that meadow hay 

 meets this requirement, but that straw does not. The 

 proportions in which straw may be mixed with other 

 foods can be calculated from the figures given in this 

 table. Thus a daily ration of 10 lbs. straw chaff and 

 6| lbs. maize would yield the required 7 lbs. of digest- 

 ible organic matter, while only one-half of the energy 

 produced would be consumed in the work of digestion, 

 leaving a sufficient balance for the remaining internal 

 work and other requirements of the body. 



The experiments of Grandeau with Paris cab horses 

 show a similar food requirement as those of Zuntz. 

 A horse of 1,000 lbs. weight, taking only half an 

 hour's walking exercise per day, required from 7 — 

 7*8 lbs. of digestible organic matter (hay), including 

 0'45 lb. of albuminoids, to maintain its condition. 



The experiments on sheep are few, and have been 

 made with comparatively rough methods. Shorn 

 sheep, fed on meadow hay, will require, according to 

 German experiments, about 11*8 lbs. of digestible 

 organic matter, containing 1*0 lb. of albuminoids, per 

 1,000 lbs. live weight, to preserve their condition. 



