(2) Bull. A bull is a mature male bovine that has not been castrated and that
possesses secondary sex characteristics, such as heavy bone and muscling, neck-
crest, and deep voice. Bulls are used in making sausage, but are not procured for troop
consumption.
(3) Bullock. A bullock is a bull that was accidentally or intentionally
castrated after reaching maturity. Stag was the term used for bullock. Bullocks are
used in making sausage, but are not procured for troop consumption.
(4) Cow. A cow is a female bovine that has given birth to a calf. Cows are
not normally marketed until they are no longer useful for milking or breeding. The
bones are hard; the ribs are flat and bowed; and the pelvic cavity is large, since it
increases in size with each birth of a calf. The aitch bone is straight or slightly curved.
(5) Heifer. A heifer is a female bovine that has not yet given birth to a calf.
It can be identified by a smooth, firm udder, and a relatively small pelvic cavity. The
udder fat (dug fat) is smooth and oval. The gracilis muscle is kidney bean-shaped. The
aitch bone terminates into fat at the dorsal posterior tip ("bone to fat"). The aitch bone is
curved with a round knob on the ventral end.
b. Four Factors for Sex Determination. Since a carcass hanging on a rail
does not retain its external and internal sex organs (penis, testicles, vulva, uterus,
ovaries, udder, and so forth), the inspector must rely on other identifying landmarks to
differentiate between males and females. There are four constant factors or criteria for
sex determination of carcass beef.
(1) Pizzle eye. The pizzle eye is the ligamentous attachment of the penis to
the pelvis and is found only in males. It is located at the posterior end of the aitch bone
and appears as a round ball of clear, translucent material with some red fibers in the
center.
(2) Bald spot. Another factor associated with males is the presence of the
bald spot. Just dorsal to the pizzle eye, there is a small area of exposed lean meat (1 to
4 inches) that is observed only in males. Females will have an outer layer of fat
covering this lean tissue. Thus, in males the term "bone to lean" and in females the
term "bone to fat" is used, depending on whether this external fat extends over the
gracilis muscle and bald spot and touches the aitch bone.
(3) Cod fat or udder fat. The third constant factor is the presence of cod fat
in males and udder fat in females.
(a) Cod fat results from the deposition of fat in the scrotum after the
male is castrated. Since the empty scrotum contracts unevenly, the fat that is deposited
is also uneven and knobby.
MD0710
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