52 ILLINOIS STATE DAIRYMEN'S ASSOCIATION 



Vitamin D 



From the standpoint of stock feeding the fourth vit- 

 amin is very important. This vitamin, which prevents the 

 disease called rickets, is known as vitamin ''D", or the anti- 

 rachitic vitamin. This disease of rickets seriously affcts the 

 bones, especially of young animals. In young animals suf- 

 fering from the disease, the calcium and phosphorus are 

 not deposited properly at the ends of the bones, where the 

 growth occurs. 



Rickets may be caused by a lack of calcium or phos- 

 phorus in the food, or by a failure of the body to assimilate 

 these minerals. Even w^hen an animal is supplied plenty 

 of calcium and phosphorus, it is apparently unable to use 

 it for bone formation unless there is plenty of the anti- 

 rachitic vitamin in its food. 



Sunlight also has an important relationship to rickets. 

 Animals in darkness or out of direct sunlight are more sus- 

 ceptible to rickets than those exposed to sunlight. 



Under winter conditions in the northern states, young 

 pigs are especially subject to rickets. They become lame 

 and stiff, particularly in their hind legs, and farmers call 

 the trouble ''rheumatism" or ''paralysis". This condition 

 can usually be prevented by including a small percentage 

 (about 5% ) of good green-colored alfalfa hay in the ration, 

 and providing plenty of calcium. Apparently dairy cows 

 may also suffer from a lack of the anti-rachitic vitamin 

 under winter conditions, as has been pointed out previously. 

 Grow More Legumes 



In conclusion let us consider what all of these recent 

 discoveries mean in terms of practical feeding of dairy 

 cattle. To me, all of these recent experiments conclusively 

 show the high value of legume hay for stock feeding, and 

 the great importance of dairy products in the human diet. 



Let us briefly review the merits of legume hay for 

 stcck feeding. First of all, you will recall that I discussed 

 the necessity of livestock getting a sufficient amount of 

 protein — in other words, a balanced ration. One of the 

 primary reasons why you should grow an abundance of 

 legumes is because they are rich in protein, alfalfa hay be- 



