308 



ESSENTIAL FATTY ACIDS 



number of the serum fatty acids as well as the kind and amount of dietary 

 fat. 



c. Spectral Analysis for Unsaturated Fatty Acids 



The total fatty acids of the serum, skin, liver, and heart consistently 

 showed high percentages of diene fatty acid^^ when adequate levels of fat 



^ te 



containing linoleic acid were fed, and all animals receiving these diets 

 presented a normal appearance of the skin and hair. The total fatty acids 

 of the serum showed more tetraene fatty acid when diets containing linoleic 

 or arachidonic acids were fed than when the diet was extremely low in fat. 

 Dogs maintained on a low fat diet and exhibiting fat-deficiency symptoms 

 showed definitely lesser amounts of diene and tetraene acids in the liver, 

 kidney, skin, and heart than animals with healthy skin. At 2350 A., E J^^m 

 values of the serum ranged from 125 to 150, and at 3000 A. from 11 to 20, 

 whereas the serum from healthy dogs receiving 15 % or more of their caloric 

 intake as fat (lard or bacon drippings) varied from 250 to 315 for the 



