A SUITABLE RATION 57 



the time indoors he can lie down. Thus, no long hay 

 is given to such a horse, but the necessary amount 

 of hay is fed as chaff, mixed with the corn ration. The 

 corn, too, is crushed to facilitate digestion. 



The effect of climate and weather must not be lost 

 sight of when fixing a ration, for with cold weather the 

 amount of food necessary to keep up the normal body 

 temperature is increased. Thus it is a common practice 

 at the beginning of winter to improve the daily ration 

 by the addition of 1 lb. of beans, although there are no 

 very good reasons why beans should be selected in pre- 

 ference to an equivalent quantity of oats, maize, or 

 barley. However, there can be no doubt that work for 

 horses is harder in winter than in summer, and the 

 practice of giving extra food is quite justified. 



The balance of the various nutrient substances, 

 digestible proteins, fats, carbo-hydrates, and fibre in the 

 total ration is a matter of supreme importance in 

 deciding upon the suitability of such for any special work. 



The "nitrogenous ratio" must be determined in 

 every case, and if this falls within the limits suggested 

 (p. 52) as suitable for various classes of work, the food 

 may generally be considered sufficiently well balanced. 

 The first step in finding the " nitrogenous ratio " of a 

 food mixture is to calculate the amount of digestible 

 protein in each of the ingredients, and, by addition, find 

 the total protein of the ration. Thus ni + n2 + n3 = N, 

 where ni, na, and n^ are the respective amounts of 

 digestible protein in the three foodstuffs of the mixture, 

 and N is the sum of them. The total fats are obtained 

 similarly, and then multiplied by the factor 2-3 (see 

 p. 35) to reduce them to their equivalent value in terms 

 of starch. The carbo-hydrates + digestible fibre of each 



