The Vermont watchman. [volume] (Montpelier, Vt.) 1883-1911, 1894-02-14

tFrom the French of Jules Crevatl
Without going into anatomical de-
tails, l will here simply explain the
most important physiological principles
of animal nutrition. From the scien-
tific point of view, animal life is vital
organizing force, possessing the power
of producing organized systems, more
or less complicated, from the elements
of organized substances drawn from
the vegetable kingdom. ["All flesh is
grass"].
shall call all foods for our live stock
"forages -; and shall show briefly how
/ our beasts draw from these forages the
material with which 10 replace the
waste of their bodies. The animal
body is traversed by more or less
regular tube or passage, known as the
alimentary canal. 1t is through this
canal that all forage must pass, to I'M
dergo the dissolvent action of various
digestive secretions, in order to sep
arate the true soluble food from the use
less insoluble woody matter, which is
expelled from the body as dung; while
the useful principles are in great part
absorbed through the membranes of
digestive canal, to enter into and be-
come part of the animals body, by way
of the blood.
The starchy matter of the food is
chiefly dissolved by the saliva, aided by
the pancreatic juice [secreted by the
organ called the sweetbread, or PAN
creas, while the protein and mineral
matters are chiefly dissolved by the gas
trio juice and the intestinal fluids. Fatty
elements are dissolved by the bile and
the pancreatic juice. The fats are not,
strictly speaking, dissolved, but are
emulsionized; the protein substances
are transformed into a substance called
albuminose, and the starchy part of the
food into glucose and Tactic acid 1.-THE
acid of sour milk. The food principles
thus divided, or dissolved, are absorbed
by the Emphatic vessels of the stomach,
and by the chyle vessels of the intes-
blood vessels. The blood, propelled by
the action of the heart, is sent through
the lungs, where it parts with the car
bonic acid, takes up the oxygen alb
sorbed by the iron of the blood glob-
ules; and is then transported by the
blood vessels to all parts of the body,
which it completely penetrates by an
infnitude of little capillary vessels. 1t
is thus that one portion of the food
elements, thus put in contact with the
tissues, is fixed and assimilated to the
body for its growth and support; while
another portion undergoes, by contact
with oxygen, true though slow con-
bustion, designed to produce the heat
necessary for the proper activity of the
animal mechanism. The blood, after
this Notwithstanding course, is COL
lected by the veins, and returned to the
heart; which again sends it to the lungs
to revivify itself with new supply of
oxygen, and to exhale the carbonic acid
collected in its course, from the COM
bustion above referred to.
The older assimilated PRINCIPLES, or
elements, which composed the bodily
tissues, undergo disorganization,
wearing out, resulting from the vital
action, the manifestations of life and
the production of work; and their old
materials, collected by the Emphatic
vessels, are returned to the current of
the blood; from which they are, as it
were, sorted out by the special glands
by the kidneys which make the urine,
the sudorific glands which make the
sweat, and the liver, which forms the
bile; for this last is also, in part at
least, an excrementitious fluid, thrown
out into the digestive canal. There
goes on, also, a continual transmutation
of all the tissues; disorganization of the
older ones, and the assimilation of new
organized principles, or elements;-a
work essentially controlled by the ner-
vous system, which presides more or
less actively over the exercise of all the
functions.
1t is the blood which supplies to the
different glands the materials needed to
form the products which they excrete;
the different digestive fluids, saliva,
gastric juice, bile, pancreatic juice, and
the intestinal fluid ;-secreted respec-
lively by the salivary glands, the fol-
licles OF the stomach, the liver, the |
pancreas, the intestinal lands;-then
the milk, secreted by the mammary
glands; the seer etions of various other |
glands; the wool, and the hair, produced |
by the papille of the skin, etc.
To complete the preceding physiolog- |
ical ideas, it will be useful to study in
detail each sort of alimentary principle,
insisting especially upon the office it |
fills in this matter of feeding.
All forage materials, of which the
kinds are 80 many and so varied, con-
tain, in very variable proportions, it is
true, only restricted number of ali
mentary principles, which can be ar
ranged into the following four classes:
The food classes here referred to are
the sugars, the fats, proteine, and min
eral substances. M. Crevat's remarks
upon each of these will be given in our
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