PRINCIPLES OF FEEDING POULTRY 



drates but with a larger proportion of carbon and a larger 

 number of atoms in the compounds. They give ofif more 

 heat or energy than the carbohydrates on account of their 

 greater carbon content. 



PRODUCTION OF NITROGENOUS AND MINERAL 

 COMPOUNDS 



The carbohydrates and fats are combined in the plant 

 with nitrogen, sulphur and phosphorus, elements obtained 

 from the nitrates and mineral salts in the soil, to form 

 more complex compounds called crude proteins. Crude 

 proteins consists of two general groups — ^proteins and 

 amids, and include all nitrogenous compounds of the 

 plants. There is approximately i6 per cent of nitrogen 

 in crude protein. The amids are the simpler forms of 

 crude proteins from which the more complex proteins are 

 constructed. They are soluble in plant juices and circu- 

 late freely throughout the plant. Our knowledge of the 

 proteins is still in the experimental stage but we do know 

 that they are very complex and many consist of a large 

 number of different combinations. Recent feeding ex- 

 periments with rats, guinea pigs and rabbits tend to show 

 very great differences in the feeding value of the different 

 proteins while some of the proteins have been found far 

 more essential to life than others. The proteins and 

 amids may be changed one to the other, the same as 

 starches and sugars are changed, according to the needs 

 of the plants. 



Crude protein is found mostly in the leaves, seeds and 



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