31)6 POULTRY PRODUCTION 



33.3 per cent. The fats in both the eggs and tlic carcass are 

 cliielly pahnitin, stearin, and olein. 



Fat stores energ>' and acts as a non-conductor of lieat, 

 the siihcutaneons deposits being a very efficient protection 

 against ci<ld. 



Nature's Provision of the Nutrients.'— The source of the 

 various nutrients in the rations of wild and domestic birds 

 is as follows: 



Natuhic riioviDES TiiF.Y soprLY Producer feeds 



Worms, grubs, and Protein. Meat scrap, milk, oil 



iiLSccts. meal, gluten-feed. 



Seeds. Carbohydrate (proteiu The grains and their by- 



and fat). products. 



Spiouts and grasses. Succulence" (water, car- Spro\itcd oats, pasture, 

 bohydrate, protein, etc. 



fat and \"itanu'ns). 

 Gravel. Ash and grit. Commercial grit, oyster 



shell, granulated hone, 

 etc. 

 Water. Water. Water. 



Mutual Relations of the Nutrients. — The elements, carbon, 

 hydrogen, and oxygen, are always present in all three of the 

 nutrients. These alone are found in the carbohydrates and 

 fats, and the practical difference between the two classes is 

 the greatly increased proportion of carbon in the case of the 

 fat. It has been found by careful experiment that fat has a 

 fuel and energy value about 2.25 times as great as does the 

 carboliytlratc, ])rinciiially because of this greater pro])or- 

 tioiial amount of carbon. That is to say, a pound of fat will 

 generate o\'cr twice as much heat as a pound of carbohydrates, 

 nr will furnish the power for more than twice as much muscu- 

 lar effort. It may therefore be said to have a feeding value 

 2.2.') times as great. 



It was shown by Voit and Lehmann (as reported by 

 Lusk'), in experiments where rice was fed to geese, that almost 

 one-third of the carbon was retained in the bodies of the 



1 Adapted from a statement of Jaffa, California Bulletin No. 1(54. 



2 Succulence is a form of feed containing a large amount of water Green 

 succulence is moat desirable because of its vitamin content. 



■Science of Nutrition. 



