52 MISC. PUBLICATION 194, U. S. DEPT. OF AGRICULTURE 



VITAMIN CONTENT OF PASTURAGE 



An adequate supply of vitamins is necessary for proper growth and 

 reproduction in livestock and to keep them tlu-ifty and resistant to 

 diseases. When animals are grazing on green, immature pasturage 

 they are better supplied with vitamins than is practical by any other 

 method. Such feed is especially rich in carotene from which vitamin 

 A is made in the animal body and contains other less well-known 

 vitamins of importance to animals. Vitamin A promotes growth and 

 increases resistance to disease. Good pasture produces milk with a 

 high content of vitamin A. Ripe pasturage bleached by exposure or 

 hay bleached in curing contains little or no carotene. 



Pasturage, like most natural feeds of farm animals, is also well 

 supplied with factors of the vitamin B complex, such as thiamin, 

 riboflavin, nicotinic acid, pantothenic acid and pyridoxin, and with 

 vitamin E. Although pasture plants are usually well supplied with 

 vitamin C, it is not known to be needed in the nutrition of farm 

 animals. 



Green vegetation contains little or no vitamin D, which gives protec- 

 tion against rickets, but being in the dhect sunlight enables animals to 

 get along without this vitamin in their feed. Cutting the pasturage 

 and curing it in the sunlight build up a supply of this vitamin. 

 Although green vegetation is deficient in vitamin D, it contains some 

 property which promotes the assimilation of calcium by dairy cattle. 



In general, approved feeding methods, such as providing good green 

 pasturage throughout the growing season, plenty of sunlight, and 

 hberal feeding of well-cured leafy hay and yellow corn during the 

 winter will take care of all the vitamin requhements of farm animals. 

 Hay a year old is not satisfactory as a source of carotene and needs to 

 be supplemented with new hay or silage. Some of the benefits of 

 pasture feeding are carried into the winter months. Hence, for 

 well-fed and well-cared-for animals there is little need of purchasing 

 commercial sources of vitamins. For poultry kept largely indoors and 

 for unthrifty bhds, cod-liver oil or some similar oil may be given to 

 supply both vitamins A and D. 



PALATABILITY A FACTOR IN PASTURE MANAGEMENT 



The palatability of pasturage depends on the kind of plants, their 

 tenderness, stage of maturity, and climatic and soil conditions. 

 Different kinds of livestock also vary in their likes and dislikes. 



In general, animals prefer legumes to grasses though there are 

 some exceptions to this preference. At the Massachusetts Agricul- 

 tural Experiment Station, on a series of plots containing various 

 grasses and forage crops, the cows preferred seedings with a high 

 proportion of timothy. Bromegrass ranks high in palatability, head- 

 ing the list of grasses at the Beltsville Research Center, Beltsville, Md. ; 

 Italian and perennial ryegrass, meadow fescue, and a pasture mixture 

 of grasses and clovers ranked next in the order stated. The palat- 

 ability of Kentucky bluegrass and orchard grass was greatly reduced 

 by seed-head formation. Hence, mowing or close grazing at heading 

 time is important for keeping the forage palatable. 



When one kmd of livestock is given a pasture much larger than the 

 animals graze down, they may eat only the most palatable plants, 

 leaving the less palatable ones to mature and become still less palat- 

 able. Under such conditions animals also avoid the vegetation near 

 their droppings. Rather than eat the less palatable forage, the stock 



