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Dairy farming was formerly confined to the spring and summer
months, when pasturage was plentiful. Cows, calving in the spring,
were allowed to become dry in the fall and were poorly fed and
sheltered during the winter. Under the present system, dairy farming
is not confined to any season; during the winter, cows are fed
succulent fodder in the form of silage, in addition to liberal
rations of grain and grain by-products, often in the form of commercially-prepared
feed. Another innovation is that, instead of manufacturing and
marketing all types of milk products, most dairy farmers now sell
all their milk to processors and distributors.
The number of dairy cows (that is, dairy cattle, exclusive of
bulls, calves, and heifers) in the United States has shown a fairly
constant change in ratio from one cow to every four persons in
the population during the late 19th century, to one to every six
in the present population. About 5 percent of the cows are purebred-that
is, of registered birth and pedigree; almost all of the remaining
95 percent belong to recognized breeds but, because they are not
qualified for registration, are known as grades. The purebreds
in the United States are mainly Holstein-Friesian, Guernsey, Jersey,
Ayrshire, and Brown Swiss (see Cattle).
Under the modern system of evaluating milk on the basis of butterfat
content, as determined by the test devised by the American agricultural
chemist Stephen M. Babcock, it is important that the dairy farmer
keep records, not only of the total production of a herd but of
the performance of individual cows. In this way the best cows
can be selected and poor producers can be replaced by better cattle.
Dairy products include whole fluid milk, low-fat fluid milk, flavored
milk, whole and nonfat dry milk, butter, cheese, evaporated and
condensed milk, frozen dairy products, and fermented products
such as sour cream and yogurt. Dairy farmers formerly separated
the cream and sold it to creameries, but in the 1950s a marked
shift occurred from the sale of farm-separated cream to the marketing
of whole milk and a coincident increase in the percentage of whole
fluid milk consumed. Since then, there has been an enormous expansion
of milk-drying facilities and increased human consumption of nonfat
dry milk solids.
Cooperative associations have helped substantially in improving
market conditions, promoting standardization and grading of dairy
products, and providing protection for the industry. Dairy cooperatives
account for about 75 percent of all the fluid milk sold in the
United States. See Cooperatives.
The introduction of labor-saving machinery, especially the vacuum
milking machine, has lightened considerably the tasks of the dairy
farmer. Modern improvements in refrigeration and transportation
have eliminated the influence of climate and adverse weather conditions
in milk distribution. Such dairy-barn equipment as feed conveyors,
washers, and sterilizers has further improved the product. Research
by governmental and association agencies has led to higher production
and greater use of dairy products and especially to the discovery
of new industrial uses for milk by-products.
Contributed by: (US) National Dairy Council
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