POULTRY FEEDS AND FEEDING 



fiber. Protein of animal origin has been found to have 

 a greater feed value for poultry than vegetable proteins 

 while in experiments with animals, proteins have been 

 found to be very different in their feeding values. The 

 flesh forming material in the feed is furnished by the 

 protein which is essential in the production of lean meat, 

 eggs, feathers, muscles, etc. It may also, if fed in excess, 

 be used as fuel or energy but is much more expensive 

 than carbohydrates as a source of energy. Carbohydrates 

 supply fuel and energy and aid in forming fatty tissue 

 after they are transformed into fats. Fats perform the 

 same function as the carbohdrates and are 2.25 times 

 as valuable as the latter as a source of heat and energy. 



PRODUCTS ESSENTIAL TO LIFE AND GROWTH 



Experiments conducted with pure chemicals to discover 

 what elements are absolutely essential to life and growth 

 show that the diet must contain protein, carbohydrates, 

 fats, inorganic salts, namely calcium, sodium and chlorine, 

 and two unidentified substances called for convenience by 

 McCullom, "Fat soluble A" and "Water Soluble B." Fat 

 Soluble (A) is associated with fats, especially with but- 

 ter fat, egg yolk fats and fats of the glandular organs 

 of animals, but not in fats or oils of vegetable origin. 

 Water Soluble (B) is not associated with fats or oils but 

 is widely distributed in various products from which it 

 can be secured by extraction with water or alcohol. It 

 is found especially in milk and leaves, fruit juices and in 

 the liver and kidneys. 



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