CALCULATION OF RATIONS 77 



The feeding standards express the physiological requirements of 

 animals for a certain production. The economy of systems of feeding 

 based on the standards does not enter into consideration, nor is it 

 possible to formulate feeding standards of general or permanent 

 yalue that take into consideration the financial side of the question 

 since the market prices of feeds vary in different places and at dif- 

 ferent times in the same places. But for the practical farmer the 

 cost of feeds is a factor of vital importance. It is of little help to 

 him to be told that he can secure a certain production of milk or meat 

 by a special system of feeding if the prices of the different feeding 

 stuffs called for make it unprofitable for him to adopt them in his 

 feeding operations. However, the standards place before the feeder 

 an ideal which he may approach as nearly as the special conditions 

 by which he is surrounded will allow. The relative cost of different 

 feeding stuffs must always be considered, and the choice of feeds 

 with which to supplement home-grown forage crops and grain 

 must be made accordingly. 



Formulating Rations. — Several considerations should receive 

 attention in formulating rations for farm animals, besides supplying 

 nutrients in the right amounts and proportions and getting an ef- 

 fective ration at as low a cost as possible. Among these are : 



First, the feeds must be palatable to the animals fed and must 

 not have any deleterious influence on their digestion or general 

 health or on the products which they furnish. A well-balanced 

 ration for milch cows can be made up of oat straw and oil meal, but 

 it would not be likely to produce satisfactory results, because of 

 the unpalatability of the ration and the large amount of roughage 

 the cows would have to consume. 



Second, the rations must contain a fair proportion of roughage 

 and concentrates ; they must not be too bulky and still must contain 

 a sufficient amount of roughage to keep up the rumination of the 

 animals, in the case of cattle and sheep, and to secure a healthy 

 condition of the animals generally. In the case of dairy cows, about 

 two pounds of hay are generally fed per hundredweight, if this is the 

 sole roughage. If silage is available, one pound of hay and three 

 pounds of silage may be fed per hundredweight, and one pound of 

 concentrates for every three to five pounds of milk produced, accord- 

 ing to the character of the roughage and the quality of the milk pro- 

 duced ; if a good quality of roughage is available, less grain may be 

 fed, and vice versa. Cows producing milk of low fat content should 

 receive less grain per pound of milk than high-testing cows. A 

 good rule for feeding grain to cows on mixed hay, corn stover, corn 

 silage, and similar low-protein roughage is to allow as many pounds 

 of grain a day as the cow gives pounds of butter fat in a week. Cows 



