A PASTURE HANDBOOK 47 



therefore in maintaining the health and productivity of Hvestock. 

 Pasturage permits the animals to replace the stores of minerals or 

 vitamins which may have been used up during the winter and also 

 enables them to lay up a supply for use durmg a period of inadequate 

 nutrition. Good pasturage appears to be a perfect feed for all her- 

 bivorous anunals except those doing hard work, giving very large quan- 

 tities of milk, or bemg fattened rapidly. On the other hand, long- 

 continued feeding of herbivorous animals on poorly cured roughages 

 is injurious to both production and reproduction. Among other 

 reasons, such feeds are deficient in carotene from which vitamin A 

 is made in the animal body. 



Although certain parasites and diseases may be largely avoided by 

 keeping livestock in dry lots or barns, animals generally are better off 

 on pastures. A clean pasture not only provides natural conditions 

 but it reduces the labor of caring for stock and also the danger of 

 mineral and vitamin deficiencies. 



The benefits of pastures over dry lots or barns are much greater 

 in the case of breeding animals than of fattenmg anunals because 

 of the plentiful supply of nutrients necessary for reproduction which 

 may not be present in dry feeds. While fattening animals need about 

 the same nutrients as breeding animals, some of the nutrients are 

 needed m lesser amounts or do not have serious effects during the 

 relatively short time involved, on the development of the fattening 

 animal. Work stock must be maintained in health for long periods 

 of time and hence are benefited by the supplementary nutrients of 

 pasturage. 



FEED VALUE OF IMMATURE PASTURAGE 



Immature pasturage, includmg both grasses and legumes, has feed- 

 ing properties similar to those of high-protein concentrates, such as 

 the oil-mUl byproducts and also contains other nutrients necessary 

 for health. It is especially well supplied with protein, minerals, and 

 vitamins. One hundred pomids of young leafy grass, containmg 25 

 pounds of dry matter when grazed, will provide enough carbohydrate 

 to produce about 50 pounds of milk and enough protein to produce 

 about 70 pounds, not including the requirements for maintenance. 

 Therefore, if young grass is to be supplemented it should be with a 

 feed rich in carbohydrates, such as the grains. 



The grass from high-yielding pastures generally contains more water 

 than the grass from low-yielding pastures. The minimum quantity 

 of dry matter contained in pasture grasses is approximately 15 per- 

 cent and occurs early in the season. Grass from an hrigated pasture 

 clipped four times in the season of 1929 at Huntley, Mont., averaged 

 23.8 percent of dry matter. The dry-matter content of grass from 

 six pasture plots at Beltsville, Md., clipped 7 or 8 times from the early 

 part of May to the early part of October, varied on an average from 

 24 percent in May to about 44 percent in August. The variations 

 in the average dry-matter content are shown m table 7, together with 

 the variations in the nutrients in both the green and dry material. 

 Although the samples gathered for analysis during the latter part of 

 the grazing season contained some mature plants, the pastures were 

 so closely grazed that most of the forage was immature and hence the 

 percentages of crude protein and crude fiber were fahly constant. 



