/l/ 30-55^ mature weight. /2/ Kllocalorles . These values represent the approximate amount of food energy actually available to and 

 capable of uae by the animal from the food absorbed. If P, C, and F represent protein, carbohydrate and fat, Ingested P,C,F - fecal 

 P,C,F = metabollzable Calories. These values are approximate only. The value for protein (=xU) allows for a 3O56 loss of virtually 

 absorbed Calories In the urine (urea, hlppuric acid, etc.). In animal husbandry, and In this table, metabollzable Calories are calcu- 

 lated from "T. D. N." ("total digestible nutrients") by multiplying grams T. D. ». by l». /}/ Air-dried (90^ dry weight). /U/ Crude 

 protein. /5/ O.OOO6 mg p-carotene = one I. U. A value of O.09 n^/kg body weight per day has been suggested for growth of swine. /6/ 

 Supplement to natural ration not necessary. /7/ Synthesized by intestinal florai /8/ Baby pigs require 0.1^ choline in diet. /$/ A 

 generic term Including cyanocobalamln (vitamin Bj2), and its hydrogenatlon product (known variously as Bi2a *•>* ^12\>) which has ap- 

 proximately the same biological activity. /lO/ Heeessary for growth and reproduction. /ll/ O.C25 ug calciferol = one I. U. /l2/ A 

 generic term Including alpha-, beta-, delta-, and gamma- tocopherols. /15/ For proper muacular nutrition. /ik/ Folic acid is not a 

 chemical entity, but a generic term for a group of factors including pteroylglutamlc acid (folacin), vitamin M, vitamin Be, factor U, 

 L. easel factor, and Norlte eluate factor. /15/ Swine synthesize most if not all they need. /16/ The antl-hemorrhagic factor. A gen- 

 eric term Including vitamin Ki (2-methyl-5-phytyl-l,U-naphtho<iulnone), synthetic vitamin K (menadione = 2-methyl-l,U-naphthoquinone), 

 and vitamin Kg (2-methyl-}-dlfameByl-l,l>-naphthoqulnone) . /17/ The term le used here as a generic term including nicotinic acid (ni- 

 acin) and, nicotinic acid amide (nicotinamide); also for pellagra preventive (P. P.) factor; and anti-blacktongue factor. The require- 

 ment may be uncertain since it depends on the protein Intake. /18/ Includes pyridoxlne, pyrldoxal, and pyridoxamlne . /19/ In NaCl. 

 /20/ Copper requirement approximately yf> Iron requirement. 



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