FIFTY-THIRD ANNUAL CONVENTION 47 



ing potassium or sodium iodide to the cows through the ges- 

 tation period. Where there is no trouble from goiter this 

 treatment is not needed. (For a full discussion and method 

 of treatment see Bulletin 350, Pages 4 to 10). 



Vitamins Are Necessary for Life 



A few years ago the word 'Vitamins" was unknown, 

 but now nearly everyone has heard of these mysterious 

 substances. Perhaps to many persons the statements made 

 concerning the marvelous effect of these compounds on the 

 human diet and likewise in stock feeding have appeared 

 highly improbable and they have wondered **Just how much 

 does all this talk about vitamins amount to anyway? Is 

 there any need of giving any consideration to them in plan- 

 ning the diet of my family or in feeding live stock?" 



Practically all the discoveries about vitamins have 

 been made in little more than a decade. Although our 

 knowledge concerning them is far from complete today, 

 yet brillant progress has been made during the past few 

 years by the scientists studying these matters. Therefore, 

 many conclusions may now be safely drawn concerning the 

 importance of vitamins in the feeding of humans and in the 

 feeding of farm animals, as well. 



Thus far five vitamins have been discovered. I will 

 take each one of these up and tell you a little about the 

 interesting story connected with it. 



Vitamin A 



The first vitamin is vitamin A, or the fat-soluble vit- 

 amin. The dairyman is especially interested in this vitamin, 

 because it is the vitamin that is present in such liberal 

 amounts in butter fat. It is absolutely essential for young 

 animals as well as old animals, and for humans as well as 

 for stock. As the diet of young children is quite limited, it 

 is very important that they get plenty of milk and other 

 dairy products, because otherwise they might not secure 

 enough of this vitamin. , 



About thirteen years ago scientists in the United States 



