24 



HOW TO FEED POULTRY FOR ANY PURPOSE WITH PROFIT 



column can tell whether an article 'be- 

 low normal in these elements makes 

 t up in the more concentrated car- 

 bonaceous elements. 



The sixth column shows the per cent 

 ol fat. In the common grains this is 

 from 2 to 5 per cent. Theoretically a 

 large per cent of fat will compensate 

 for a deficiency in starch, etc., but in 

 practice it is found that the large use 

 o* f ats makes a feed either unpalata- 

 ble to the birds or injurious to their 

 digestive organs, hence the article 

 with high per cent of fat is to be con- 

 sidered chiefly in view of the possi- 

 bility of making this supply deficiency 

 of fat in more bulky materials. 



The seventh column gives the nutri- 

 tive ratio; that is, the ratio of the 

 flesh formers to the heat and energy 

 producers. The percentage of the 

 nutritive elements in a feed being 

 known, the method of computing the 

 nutritive ratio is as follows: The fat 

 is reduced to terms of carbohydrates 

 by multiplying by 2.25, this being done 

 because fat has 2.25 times the heat and 

 energy producing capacity of the car- 

 bohydrates. This result added to the 

 carbohydrates gives us the total of the 

 heat-producing elements. The remain- 

 der of the process is simply a matter 

 of statement, and of reducing the state- 

 ment to its lowest numerical terms. 



To illustrate with corn: Multiplying 

 the 5 per cent of fat by 2.25 we find 

 that it is equivalent to 11.3 per cent of 

 carbohydrates. Adding this to 70.3 (the 

 value of the carbohydrates), we have 

 81.6 as the total percentage of heat 

 producers. The percentage of protein 

 is 10.4. Expressing the two quantities 

 in the form of a ratio we have 10.4:81.6, 

 and reducing this to its simplest terms 

 we have 1:7.9 as the nutritive ratio of 

 corn. The ratio is independent of the 

 quantities of the feed, it is simply an 

 expression of the relative proportions 

 of the elements in the feed. 



The last column gives the fuel value, 

 a term synonymous with potential 

 energy and preferred for use in tables 

 because it is shorter. This value is an 

 actual and not a relative one, and must 

 be taken for specific quantities of arti- 

 cles. In tables of poultry feeds it is 

 usual to give the number of heat units 

 in one ounce. One advantage of this is 

 that the common grains happen to 

 have an energy of about 100 calories 

 per ounce, and taking this as the aver- 

 age normal requirement we have 100 

 as a convenient standard for ordinary 

 mental comparisons and calculations 

 such as we make generally in practical 

 feeding. 



The fuel value of an article is as- 

 certained originally by burning it and 

 measuring the resultant heat. The 

 fuel values of its different elements 

 are ascertained by burning them sep- 

 arately after they have been chemical- 

 ly separated. In this experimental 

 way it was found that an ounce of pro- 

 tein and an ounce of carbohydrates 

 have the same fuel value 116 calories, 

 while an ounce of fat has a fuel value 

 of 264 calories. (It will be noted that 

 this is a little more than indicated by 

 the factor 2.25 which we use in reduc- 

 ing fat to terms of carbohydrates in 

 determining nutritive ratios. The 264 

 is accurate; the other disregards a 

 small fraction). The calculation of fuel 

 value in an ounce of a feed therefore is 

 simply a matter of finding the value of 

 the combined protein and carbo- 

 hydrates, by multiplying the percent- 

 age of the two by 116, then finding 

 the value of the fat by multiplying the 

 percentage of fat by 264; and adding 

 these results. 



Taking corn as an example: An 

 ounce of corn is 10.4 per cent protein 

 and 70.3 per cent carbohydrates; that 

 is, 80.7 per cent of 'it has a fuel value 

 of 116 calories per ounce. If an ounce 

 has a fuel value of 116 calories, 80.7 

 per cent of an ounce has a value of 

 (116 x .807) calories, or disregarding 

 the third decimal (116 x .80) calories, 

 which gives us 92.8 calories as the 

 heat value of these elements. Corn 

 being 5 per cent fat, and fat having 

 a fuel heat value of 264 calories per 

 ounce, the heat value of the fat in an 

 ounce of corn is found by multiply- 

 ing 264 x .05, which gives us 13.2 

 calories in the fat in an ounce of corn. 

 Combining our two results we have 

 92.8 plus 13.2 equals 106. 



Analyses and Nutritive Values of Articles That Are or May Be Fed to Poultry 



(Continued) 



jaJC 

 cfi w 



1.7 

 2.8 

 3.5 



0.4 

 7.3 

 8.8 

 0.7 



3.0 



3.3 



23.6 



3.5 



3.6 



3.6 



3.8 



19.5 



13.1 



35.6 



30.4 



7.9 



3.0 



21.0 



42.5 



3.0 



1.4 



1.2 



1.7 



2.0 



1.6 



1.4 



16.9 



18.9 



8.0 



18.1 



4.7 



1.0 

 0.8 

 1.1 

 0.7 

 0.6 

 0.9 

 0.4 

 0.2 

 0.5 

 0.8 

 0.6 

 0.4 

 0.6 

 0.3 

 0.2 

 0.2 

 0.5 

 0.4 



2.9 

 3.3 

 2.2 

 2.5 



2.9 

 2.1 

 1.4 

 2.0 

 3.4 

 2.7 

 1.4 



1:7.2 

 1:4.8 

 1:4.2 



2.2 1 :7 

 4.4 1 :3.8 

 7.1 1:2.1 



1:10.9 

 1:6.5 

 1:5.9 



1:11.2 



1:8.3 



1:5.3 



1:6.3 



1:7.6 



1:7.3 



1:8.6 



1:9.2 



1:3.5 



1:1.3 



1:5 



1:4.8 



1:1.7 



1:1.4 



1:9.7 



1:6.3 



1:2.4 



1:2.8 



1:2.6 



1:3 



1:2.4 



1:3 



1:2.5 



1:2.1 



1:2.6 



1:1.4 



1:3 



1:4.4 



1:7 



1:1.6 



1:3.7 



1:1.9 



1:3.5 



1:4 



1:7 



1:5 



1:4 



1:2.6 



1:3.5 



1:2.9 



1:3.5 



1:2.3 



1:2.7 



1:2.1 



1:1.7 



1:2 



1:2.9 

 1:3.7 

 1:3.4 

 1 :8.7 



"3 3 

 3*3 



100 

 98 

 98 



83 



85 



101 



102 

 80 

 95 

 48 



106 



82 



105 



95 



95 



102 



102 



101 



111 



141 



137 



99 



91 



119 



147 



85 



92 



85 



78 



93 



93 



90 



117 



123 



100 



119 



97 



15 

 15 

 23 

 17 

 14 

 18 

 13 



9 

 14 

 12 

 14 

 13 

 13 



5 



8 



4 



6 



71 

 67 

 71 

 66 



