Richmond times-dispatch. [volume] (Richmond, Va.) 1914-current, 1918-08-04
DIGESTIVE ORGANS
FUNCTION DESCRIBED
Without Teeth, Mastication Takes
Place in Gizzard Of
Fowl.
TONGUE. GULLET AND CROP
Explanation Of Necessity for Good.
sharp Grit and Bulky Foodstuffs
as Part OF Fowls Dict-Dcscribcs
Crop-Bound Condition.
ny II. ARMSTRONG ROBERTS.

By II. ARMSTRONG R0DERTS.
A knowledge OF the digestive system
If fowls is essential to intelligent feed
Ing. The poultryman is told TO feed
this and that. to keep grit before the
flock and 10 give the birds n certain
amount OF bulky food all of which he
may do. But. unless he understands
the reasons for so doing. he cannot
have the right sort OF confidence III his
work To work at task blindly sell
dom produces the best results Then
again should sickness break out
among the birds tho poultryman Is Sc
riously Handicapped unless he has
IA miliarity with the inside workings"
the machinery. SO 10 speak.
To describe the digestive machinery
with as little technical matter as pos
sble is the object Of this article, and
If the writer seems a little vague on
some points il is because scientific data
is not availah le. 1t is unfortunate that
we have not the knowledge Of poultry
In connection with digestion and feed
ing standards that we have of other
farm animals.
The main reason for this seems to
lie in certain difficulties OF technique
encountered in experimental work
This is obvious when one considers the
great differences III anatomical Struc-
ture between birds and mammals.
Then, too, fowls are less adaptable.
The body temperature of birds is con-
siderably higher than that of nam
mails. and their respiration is much
more rapid. owing to their energetic
temperament they do not bear conHne-
nent well enough TO provide good
specimens for certain Investigations.
DIGESTION AND ASSIMILATION
MORE DIRECT THAN IN ANIMALS
In accord with the lower evolution
airy position of birds as contrasted
with mammals. the digestive tract Of
fowls is much simpler than the viccra
OF animals. The absence of teetch for
mastication. the storage of food in the
crop and the peculiar muscular action
of the Gizzard. which takes the place
OF mastication in the mouth. are char
acteristics found only in birds. Then
too. the intestines OF birds fail to
show the well-detined subdivisions so
conspicuous in animals. In a measure
the digestion and assimilation of food
is much more direct in fowls. 1t is
still simpler in fish. and so on. until
we reach the lowest forms OF animal
life.
Instead OF mouth and lips. the mouth
parts OF birds consist of a horny man
dible on each jaw. forming the bcak
of the land fowl and the bill OF the
water fowl In chickens the beak is
comparatively short, pointed. thick and
ing slightly over the lower nandtblc
An extreme curve is fond in such birds
as the parrot and eagle, thus giving
great power to tho beak
In water fowl the bill is relatively
longer, less rigid. hatter widcned at
Its outer end and shaped like Il SCOOP.
Within the mouth along the edges Of
both mandibies arc rows of tiny pro-
Jections, resembling rudimcntary teeth.
grasses and other soft hcrbaEc
Whereas the beak OF chicken or
turkey is designed TO pick up food or
tear II loose, the bill of water fowl
Is built TO work like n scoop. For in
stance 1t will be noted that a duck
seems to shovel UP its food Geese
forage with a hurrowing movement Of
the bill. much the same as a pig roots
in the soil.
Needless 10 say. the neck muscles OF
birds are corresponding!y strong
Geese especially can deliver a vicious
blow with their bills. as many child
can attest who has been attacked by
them Muscovy ducks arc known to
kill each other by the great power of
their bills
The tongue in chickens. turkeys and
guinea fowls is.shapen like the harbed
head OF an arrow. It is sharply pointed
and rests in a hollow in the lowe,
mandinle II does not project from
the mouth as in animals. The projec
tons "a the back Of tho tongue serve
10 force tho food toward the entrance
10 the esonhagus. as the tongue moves
forward and back and to keep the
food clear OF the windpipc
In water fowl the tongue is wider
and softer. 10 conform TO the shape Of
bill and is more flexible than tho
tongues OF chickens or turkeys.
While domestic birds have rl,di,pept
AIRY glands in the mouth for the score
ton Of fluid, as salivary glands they
arc imperfcCtly developed Saliva Is
unnecessary. inasmuch as the food l..
swa!!o"ed whole Therefore. the cher
aim Of this mouth secretion is 10 keep
the membranes moist. 10 aid in the pas
sage OF the food
After leaving the mouth the food
enters the esophagus. or Fullet, which
.is distinguished by its capacity 10 az
pand This canal cmpti"s into the croa
pouch which acts storage place
for the food eaten. and corresponds 10
the paunch OF ruminants
The duck has no crop. the food pass
ing directly from the Rullct TO the eiz-
Yard. and as consequence the food
must be more or less moist soft to,1
is the ducks natural diet, together with
grasses. vegetables and animal foot
Too much dry, hard grain does no,
agree with ducks. Most breeders give
them nothing but wet mash anu
green food
In land fowl the purpose o. ,hr
crop is 10 soften the food both .,
means OF the mucus carried dowr
from the mouth and the secretion OF
the mucous glands OF the crop itself
The latter secretion is quite profuse
Grain and other hard substances re-
main in the crop for some time. ire
quently as long as twelve hours
Sometimes the food IS unable to leav.
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