b. Five Classes of Slaughter or Feeder Swine. Since sex has no effect on
their physical characteristics, the inspector does not need to differentiate between male
and female carcasses. They are treated as a single class for grading. The classes are
(1) Boar. A mature male swine that has not been castrated and is used for
breeding purposes (corresponds to a bull).
(2) Barrow. A male swine castrated when young and before development of
the secondary physical characteristics (reaching sexual maturity) of a boar.
(corresponds to a steer).
(3) Stag. A male swine castrated after development or beginning of
development of the secondary physical characteristics (reaching sexual maturity) of a
(4) Sow. A mature female swine that usually shows evidence of having
reproduced. (corresponds to a cow).
Gilt. A young female swine that has not produced young. (corresponds
to a heifer).
Although there are USDA quality grades for pork, these do not carry through to
the retail level, as do the grades for other kinds of meat. Because of this consistency,
USDA grades for pork reflect only two levels of quality, Acceptable and Unacceptable.
Acceptable quality pork is then graded for yield, that is, the yield ratio of lean to waste.
Unacceptable quality pork which includes meat that is soft and watery is graded U.S.
Utility. The quality of pork is determined by the lean and firmness of the fat, and the
characteristics related to the combined carcass yields of the four lean cuts, ham, loin,
picnic shoulder, and Boston butt. The official grades of slaughter barrows and gilts are:
a. United States Number 1.
b. United States Number 2.
c. United States Number 3.
d. United States Number 4.
e. United States Utility.
The Armed Forces does not normally procure hogs in the form of carcasses.
Market cuts are purchased, and they are normally from carcasses, which
would be graded as US Number 1 or US Number. 2.