Page 38 - Mammal (DK Eyewitness)

Unique to mammals

The mammary glands, unique to the
mammalian mother, form in the skin.
They resemble specialized sweat
glands and grow in two milk lines
on each side of the abdomen.
Cats and dogs have several
glands and teats along each
A mare has two teats between her side; in hoofed animals
back legs. She nudges her foal
toward them; the foal then feeds they are near the
on average about 4 times each hour.
hind legs. In
primates (including humans) they are on
the chest, a site that may be connected
with adaptation to a tree-dwelling life
and the consequent need to hold the
babies with the forelimbs. During
pregnancy, the mammary glands
increase in size under the
influence of the female hormones
estrogen and progesterone. Milk
production is stimulated by
another hormone, prolactin.
After birth a hormone
called oxytocin, from
the pituitary gland (just
under the brain),
causes the gland to
release its milk and
encourages formation of more
milk. Milk is the young mammal’s
complete food, providing even
the water it needs.

THE NEAT TEAT
Unlike kittens, puppies usually feed from
whichever teat they can find. The teat is a
rubbery-textured lobe of tissue. It fits The mother cat (p. 34)
neatly inside the baby’s mouth, to with her third, much
minimize loss of milk as the baby suckles. smaller, litter
The teat also acts like a shut-off valve to
prevent leakage of milk after feeding. CONTENTED CAT AND KITS
Within an hour of birth, a kitten is suckling (sucking milk
from its mother’s teat). Since there is usually about
20 minutes between the births of successive littermates,
and there are four or five kittens in an average litter, the
first-born will already be suckling when the later ones
arrive. The tiny kitten, although unable to see or hear, can
smell - and can feel with its whiskers, fur, nose, and feet.
It moves to the milk supply by scrabbling with its feet,
first locating the warmth of the mother’s body, then
working its way along until it finds a teat. It kneads the
teat with its feet and face, to stimulate milk flow. After an
initial free-for-all, each kitten tends to settle into a routine
and suckle from its own teat. If there is a large litter, the
young may feed in shifts.
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