FEEDING STANDARDS 137 



economical, so that the standard given may often be profitably 

 increased. 



"Standards for milch cows are given for the middle of the 

 lactation period with animals yielding milk of average com- 

 position. 



"The standards for growing animals contemplate only a moderate 

 amount of exercise; if much is taken, add 15 per cent., (mostly 

 non-nitrogenous nutrients) to the ration. If no exercise is taken, 

 deduct 15 per cent, from the standard." 



Explanation of Table II. The table on feeding standards is 

 divided into two parts, A and B. Table A gives the amounts 

 of dry matter and digestible nutrients required per day for 

 farm animals under all conditions of work and rest. This table 

 is based on 1,000 Ibs. live weight. Table B is similar to Table 

 A, except that the standards are based on the weights of the 

 animals as mentioned. To make this clearer, the first standard 

 in Table A is for "oxen at rest in stall." The standard reads 

 17.5 Ibs. dry matter, 0.7 Ibs protein, 8.3 Ibs. carbohydrates and 

 fat, 9.0 Ibs. total, with a nutritive ratio of 1 : 11.9. This stand- 

 ard is for oxen, weighing 1,000 Ibs., at rest in the stall. The 

 first standard in table B is for growing cattle 2-3 months old 

 weighing 150 Ibs. The standard reads 3.3 Ibs. dry matter, 0.6 

 Ibs. protein, 2.8 Ibs. carbohydrates and fat, 3.4 Ibs. total, with 

 a nutritive ratio of I : 4.6. This standard is figured on growing 

 cattle weighing 150 Ibs. 



The digestible carbohydrates, fiber and fat are included in the 

 column, carbohydrates and fat. The fat is reduced to terms of 

 carbohydrates and the digestible fiber is added to the carbohy- 

 drates because it is considered of equal value. 



A study of the table reveals a difference in the standards for 

 the same class of animal according to the purpose for which the 

 animal is fed. These standards therefore may be called feed 

 requirements. The feed requirements may be considered for 

 maintenance, growth, work, milk production and fattening. 



Maintenance Requirements. We learned that no matter how 

 still an animal might be, a supply of food is necessary to keep the 

 animal alive. The amount of dry matter and digestible nutrients 



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