BULLETIN 128. 



To make the above calculation perfectly plain it should be 

 noted that Table 2 (p. 5), says that 100 Ibs. of bran contain 12.2 

 Ibs. of protein. If 100 Ibs. contain 12.2 Ibs., 6 Ibs. of bran will 

 contain six hundredths of 12.2 Ibs. or .06 X 12.2, which equals 

 0.732 Ibs. of protein. The method is the same in the remaining 

 computations. 



The above ration is satisfactory so far as total nutrients are 

 concerned, but is open to the criticism that the amount of nitro- 

 genous matter is too large in proportion to the non-nitrogenous 

 matter. This could easily have been avoided by substituting 

 some corn for cotton seed meal, but owing to the very high 

 price of the former and the relatively low cost of the latter, in 

 South Carolina, such a substitution would be undesirable, be- 

 cause of the increased cost of the ration. 



Nutritive Ratio.-^-ln speaking of rations, the terms "wide" 

 ration and ' 'narrow" ration are frequently ured. The terms 

 refer to the proportion of nitrogenous to non-nitrogenous mat- 

 ter in the ration. This proportion is spoken of as the nutritive 

 ratio, which is obtained by dividing the digestible carbohydrates 

 plus 2.4 (heat equivalent of carbohydrates) times the digestible 

 ether extract, by the digestible protein. In the ration calculated 

 above the nutritive ration = (10.14 plus 2.4 X -986) -=- 2.71 = 

 4.6, that is, the nutritive ratio in this case is 1 :4.6. 



When the amount of nitrogenous matter is small as com- 

 pared with the non-nitrogenous matter, the ration is said to be. 

 "wide." When the reverse is true, the ration is said to be 

 "narrow." 



Proportion of Roughage and Concentrates. According to 

 our feeding standard, a cow yielding 22 pounds of milk requires 

 a ration containing 16 pounds of dibestible nutrients and a total 

 of 29 pounds of dry matter (digestible and indigestible). This 

 amount of dry matter means that the ration must have a fairly 



