1574 The Cornell Reading-Courses 



the standards in Table 2 are given in terms of dry matter, digestible 

 protein, and total nutriment. In order to obtain the total nutriment, the 

 fat has been multiplied by 2j and the carbohydrates and protein added. 



Factors in an ideal ration 



In actually computing a ration for a given purpose there are seven 

 factors that should be considered: 



1 . Amount of dry matter 



2. Digestibility of the ration 



3 . The nutritive ratio 



4. Variety in the ration 



5. Suitability of the foods to the animal 



6. Palatability of the ration 



7. Cost of the ration 



Amount of dry matter. — In the table of feeding standards, the amount 

 of dry matter has been indicated for each purpose to be served. The 

 amount of dry matter in the ration serves to regulate the relative amounts 

 of roughage and concentrates. By roughage are meant the coarser foods, 

 such as hay, corn fodder, silage; by concentrates are meant the grains, 

 and the other foods in the ration that are low in their percentage of fiber 

 and water and high in their percentage of total nutriment. Ordinarily, 

 in rations for cattle and sheep, if two thirds of the dry matter is from 

 foods classed as roughage and one third from concentrates, the ration 

 will be bulky enough to distend the digestive organs so as to give the best 

 results. For horses and swine, more dry matter should be in the grain. 



Digestibility of the ration. — A little more than two thirds of the dry 

 matter in the ration should be digestible; that is, the amount of total 

 nutriment should be at least two thirds as much as the dry matter. This 

 relation will change with the purpose of the ration and with the character 

 of the food. Any ration for productive purposes, however, which shows 

 that the amount of total nutriment is less than two thirds as much as 

 the amount of dry matter, can be improved. 



The nutritive ratio. — In Table 2 the nutritive ratio for each purpose 

 has been indicated. It will be noticed that the rations for growing animals 

 and for milk production are 1 : 6 or narrower, while the rations for fatten- 

 ing and for labor may be somewhat wider. In none of the rations except 

 in the case of the youngest animals does the nutritive ratio go below 

 1:4.5. Formerly, it was thought that feeders must calculate the nutri- 

 tive ratio, or " balance " the ration, with much exactness. This is no 

 longer considered to be necessary, due to further knowledge in respect 

 to the function of the nutrients and to the fact that the nutrient protein 

 is not so expensive as in former years. If the nutritive ratio given for 

 the purpose is considered to be the widest ration for the best results, 



