14 BULLETIN 1360, U. S. DEPARTMENT OF AGRICULTURE 
possible and has developed physical characteristics peculiar to its 
class. As a rule the animal is castrated when it is not more than 
a few weeks old, but on the range castration is sometimes deferred 
until the calf is 3 or 4 months old (fig. 1). 
Heifer—A heifer is a female bovine animal which has never had 
a calf and which has not reached a state of advanced pregnancy 
fg =D) 
Cow.—A cow is a female bovine animal which has had one or 
more calves or which has reached an advanced stage of pregnancy 
(fig. 3). 
Bull——A bull is an uncastrated male bovine animal which has 
reached sufficient maturity to make reproduction possible and has 
developed physical characteristics peculiar to its class. Bulls as 
a class show greater development of masculine characteristics than 
do stags (fig. 4). 
Stag—A stag is a male bovine animal which was castrated after 
it had reached sufficient maturity to make reproduction possible and 
which has developed many of the physical characteristics peculiar 
to the adult uncastrated male (fig. 5). 
SUBCLASSES OF CATTLE 
The next groups into which cattle are divided are called sub- 
classes. Subclasses are formed on the basis of peculiar suitability 
for certain general purposes. As a rule, market classes of cattle are 
divided into three subclasses—slaughter (see fig. 1), feeder (fig. 6), 
and stocker (fig. 7). There are some variations, the number of sub- 
classes of cows being increased to five by the addition of milkers 
and springers, whereas all stags are combined in a single subclass 
called slaughter. 
Theoretically there might be just one subclass—slaughter—because 
cattle of practically every description are slaughtered. Furthermore, 
any bovine animal offered on the market can find a place in the 
slaughter subclass. 
General market practice, however, discriminates between animals 
on the basis of relative suitability for certain purposes. Hence, 
although it is perfectly possible to slaughter any individual animal 
and thereby produce a certain quantity of edible meat of a certain 
gerade, it frequently happens that the animal possesses character- 
istics which render it particularly suitable for further feeding, 
breeding, or other purpose than immediate meat production. As 
the terms slaughter, feeder, and stocker as they apply to all 
kinds of meat animals have been defined, detailed discussion is 
unnecessary here. 
There are two additional subclasses of cows—milkers and springers. 
A milker is a cow which is giving milk, usually one which has 
recently had a calf. This subclass is largely confined to animals of 
dairy breeding or cows to be utilized for milk production. 
A springer is a pregnant female bovine animal, usually one which 
is due to calve within a short time. As received in public stockyards 
springers are usually due to calve within a few days. The same 
limitations regarding breeding and utilization apply in springers as 
in milkers, 
