2
Products of the animal industry furnish raw materials for many
important processing industries, such as meat packing, dairy
manufacturing, poultry processing, textile production, and
tanning. Many services are based on the needs of the animal
industry, including livestock marketing, milk deliveries, poultry
and egg marketing, poultry hatcheries, artificial insemination
services, feed manufacturing, pharmaceutical purposes, and
veterinary services. Thus, animal science involves the applica-
tion of scientific principles to all phases of animal production
(Fig. 2), furnishing animal products efficiently and abundantly
to consumers. Products from animals are often used for con-
sumer products other than food, for example, hides for leather,
and organ meats for the preparation of drugs and hormones.
Livestock breeding
The breeding of animals began thousands of years ago. A breed
is a group of animals that has a common origin and possesses
characteristics that are not common to other individuals of
the same species; a purebred breed is a group that possesses
certain fixed characteristics, such as color or markings, which
are transmitted to the offspring. During the last half of the nine-
teenth century, livestock breeders made increasing progress
in producing animals better suited to the needs of humans
by simply mating the best to the best. However, in the twen-
tieth century, animal breeders began to apply the scientific
principles of genetics and reproductive physiology, and these
disciplines remain areas of active investigation in the twenty-
first century.
The modern animal breeder has genetic tools, such as selec-
tion, inbreeding, and outbreeding. Selection involves the re-
taining or rejecting of a particular animal for breeding purpos-
es, based largely on qualitative characteristics. Inbreeding is a
system of breeding related animals. Outbreeding is a system of
breeding unrelated animals. When these unrelated animals are
of different breeds, the term crossbreeding is usually applied.
Agricultural Science (Animal) (continued)
+
ward
'
s
science
Fig. 2: The application of scientific principles to all phases of animal production is necessary for the production of healthy livestock. The watering of cattle is an important way to help these
animals keep cool and less stressed during periods of excessively hot weather.
(Credit: Keith Weller, Agricultural Research Service/U.S. Department of Agriculture)
