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The Milk-mirror






Category: History and Breeds

The discovery of M. Guenon, of Bordeaux, in France--a man of remarkable
practical sagacity, and a close observer of stock--consisted in the
connection between the milking qualities of the cow and certain external
marks on the udder, and on the space above it, called the perineum,
extending to the buttocks. To these marks he gave the name of
milk-mirror, or escutcheon, which consists in certain perceptible spots
rising up from the udder in different directions, forms and sizes, on
which the hair grows upward, whilst the hair on other parts of the body
grows downward. The reduction of these marks into a system, explaining
the value of particular forms and sizes of the milk-mirror, belongs
exclusively to Guenon.



He divided the milk-mirror into eight classes, and each class into eight
orders, making in all no less than sixty-four divisions, which he
afterward increased by subdivisions, thus rendering the whole system
complicated in the extreme, especially as he professed to be able to
judge with accuracy, by means of the milk-mirror, not only of the exact
quantity a cow would give, but also of the quality of the milk, and of
the length of time it would continue. He endeavored to prove too much,
and was, as a matter of consequence, frequently at fault himself.

Despite the strictures which have been passed upon Guenon's method of
judging of cows, the best breeders and judges of stock concur in the
opinion, as the result of their observations, that cows with the most
perfectly developed milk-mirrors are, with rare exception, the best
milkers of their breed; and that cows with small and slightly developed
milk-mirrors are, in the majority of cases, bad milkers. There are,
undoubtedly, cows with very small mirrors, which are, nevertheless,
very fair in the yield of milk; and among those with middling quality of
mirrors, instances of rather more than ordinary milkers often occur,
while at the same time it is true that cases now and then are found
where the very best marked and developed mirrors are found on very poor
milkers. These apparent exceptions, however, are to be explained, in the
large majority of cases, by causes outside of those which affect the
appearance of the milk-mirror. It is, of course, impossible to estimate
with mathematical accuracy either the quantity, quality, or duration of
the milk, since it is affected by so many chance circumstances, which
cannot always be known or estimated by even the most skillful judges;
such, for example, as the food, the treatment, the temperament,
accidental diseases, inflammation of the udder, premature calving, the
climate and season, the manner in which she has been milked, and a
thousand other things which interrupt or influence the flow of milk,
without materially changing the size or shape of the milk-mirror. It
has, indeed, been very justly observed that we often see cows equally
well formed, with precisely the same milk-mirror, and kept in the same
circumstances, yet giving neither equal quantities nor similar qualities
of milk. Nor could it be otherwise; since the action of the organs
depends, not merely on their size and form, but, to a great extent, on
the general condition of each individual.




The different forms of milk-mirrors are represented by the shaded parts
of cuts, lettered A, B, C, D; but it is necessary to premise that upon
the cows themselves they are always partly concealed by the thighs, the
udder, and the folds of the skin, which are not shown, and therefore
they are not always so uniform in nature as they appear in the cuts.



Their size varies as the skin is more or less folded or stretched; while
the cuts represent the skin as uniform or free from folds, but not
stretched out. It is usually very easy to distinguish the milk-mirrors
by the upward direction of the hair which forms them. They are sometimes
marked by a line of bristly hair growing in the opposite direction,
which surrounds them, forming a sort of outline by the upward and
downward growing hair. Yet, when the hair is very fine and short, mixed
with longer hairs, and the skin much folded, and the udder voluminous
and pressed by the thighs, it is necessary, in order to distinguish the
part enclosed between the udder and the legs, and examine the full size
of the mirrors, to observe them attentively, and to place the legs wide
apart, and to smooth out the skin, in order to avoid the folds.

The mirrors may also be observed by holding the back of the hand against
the perineum, and drawing it from above downward, when the nails rubbing
against the up-growing hair, make the parts covered by it very
perceptible.

As the hair of the milk-mirror has not the same direction as the hair
which surrounds it, it may often be distinguished by a difference in the
shade reflected by it. It is then sufficient to place it properly to the
light in order to see the difference in shade, and to make out the part
covered by the upward-growing hair. Most frequently, however, the hair
of the milk-mirror is thin and fine, and the color of the skin can
easily be seen. If the eye alone is trusted, we shall often be deceived.



In some countries cattle-dealers shave the back part of the cow. Just
after this operation the mirrors can neither be seen nor felt; but this
inconvenience ceases in a few days. It may be added that the
shaving--designed, as the dealers say, to beautify the cow--is generally
intended simply to destroy the milk-mirror, and to deprive buyers of one
means of judging of the milking qualities of the cows. It is unnecessary
to add that the cows most carefully shaven are those which are badly
marked, and that it is prudent to take it for granted that cows so shorn
are bad milkers.

Milk-mirrors vary in position, extent, and the figure which they
represent. They may be divided according to their position, into mirrors
or escutcheons, properly so called, or into lower and upper tufts, or
escutcheons. The latter are very small in comparison with the former,
and are situated in close proximity to the vulva, as seen at 1, in cut
E. They are very common on cows of bad milking races, but are very
rarely seen on the best milch cows. They consist of one or two ovals, or
small bands of up-growing hair, and serve to indicate the continuance of
the flow of milk. The period is short, in proportion as the tufts are
large. They must not be confounded with the escutcheon proper, which is
often extended up to the vulva. They are separated from it by bands of
hair, more or less large, as in cut marked F.



Milk-mirrors are sometimes symmetrical, and sometimes without symmetry.
When there is a great difference in the extent of the two halves, it
almost always happens that the teats on the side where the mirror is
best developed give more milk than those of the opposite side. The left
half of the mirror, it may be remarked, is almost always the largest;
and so, when the perinean part is folded into a square, it is on this
side of the body that it unfolds. Of three thousand cows in Denmark,
but a single one was found, whose escutcheon varied even a little from
this rule.

The mirrors having a value in proportion to the space which they occupy,
it is of great importance to attend to all the rows of down-growing
hairs, which diminish the extent of surface, whether these tufts are in
the midst of the mirror, or form indentations on its edges.

These indentations, concealed in part by the folds of the skin, are
sometimes seen with difficulty; but it is important to take them into
account, since in a great many cows they materially lessen the size of
the mirror. Cows are often found, whose milk-mirrors at first sight
appear very large, but which are only medium milkers; and it will
usually be found that lateral indentations greatly diminish the surface
of up-growing hair. Many errors are committed in estimating the value of
such cows, from a want of attention to the real extent of the mirror.

All the interruptions in the surface of the mirror indicate a diminution
in the quantity of the milk, with the exception, however, of small oval
or elliptical plates which are found in the mirror, on the back part of
the udders of the best cows, as represented in the cut already given,
marked A. These ovals have a peculiar tint, which is occasioned by the
downward direction of the hair which forms them. In the best cows these
ovals exist with the lower mirrors very well developed, as represented
in the cut just named.

In short, it should be stated that, in order to determine the extent and
significance of a mirror, it is necessary to consider the state of the
perineum as to fat, and that of the fullness of the udder. In a fat cow,
with an inflated udder, the mirror would appear larger than it really
is; whilst in a lean cow, with a loose and wrinkled udder, it appears
smaller. Fat will cover faults--a fact to be borne in mind when
selecting a cow.

In bulls, the mirrors present the same peculiarities as in cows; but
they are less varied in their form, and especially much less in size.

In calves, the mirrors show the shapes which they are afterwards to
have, only they are more contracted, because the parts which they cover
are but slightly developed. They are easily seen after birth; but the
hair which then covers them is long, coarse, and stiff; and when this
hair falls off, the calf's mirror will resemble that of the cow, but
will be of less size.

With calves, however, it should be stated, in addition, that the
milk-mirrors are more distinctly recognized on those from cows that are
well kept, and that they will generally be fully developed at two years
old. Some changes take place in the course of years, but the outlines of
the mirror appear prominent at the time of advanced pregnancy, or, in
the case of cows giving milk, at the times when the udder is more
distended with milk than at others.

M. Mayne, who has explained and simplified the method of M. Guenon,
divides cows, according to the quantity which they give, into four
classes: first, the very good; second, the good; third, the medium; and
fourth, the bad.

In the FIRST class he places cows, both parts of whose milk mirror, the
mammary--the tuft situated on the udder, the legs and the thighs--and
the perinean--that on the perineum, extending sometimes more or less out
upon the thighs--are large, continuous, and uniform, covering at least
a great part of the perineum, the udder, the inner surface of the
thighs, and extending more or less out upon the legs, as in cut A, with
no interruptions, or, if any, small ones, oval in form, and situated on
the posterior face of the udder.



Such mirrors are found on most very good cows, but may also be found on
cows which can scarcely be called good, and which should be ranked in
the next class. But cows, whether having very well developed mirrors or
not, may be reckoned as very good, and as giving as much milk as is to
be expected from their size, food, and the hygienic circumstances in
which they are kept, if they present the following characteristics:
veins of the perineum large, as if swollen, and visible on the
exterior--as in cut A--or which can easily be made to appear by pressing
upon the base of the perineum; veins of the udder large and knotted;
milk-veins large, often double, equal on both sides, and forming
zig-zags, under the belly.

To the signs furnished by the veins and by the mirror, may be added also
the following marks: a uniform, very large, and yielding udder,
shrinking much in milking, and covered with soft skin and fine hair;
good constitution, full chest, regular appetite, and great propensity to
drink. Such cows rather incline to be poor than to be fat. The skin is
soft and yielding; short, fine hair; small head; fine horns; bright,
sparkling eye; mild expression; feminine look; with a fine neck.

Cows of this first class are very rare. They give, even when small in
size, from ten to fourteen quarts of milk a day; and the largest sized
from eighteen to twenty-six quarts a day, and even more. Just after
calving, if arrived at maturity and fed with good, wholesome, moist food
in sufficient quantity and quality, adapted to promote the secretion of
milk, they can give about a pint of milk for every ten ounces of hay, or
its equivalent, which they eat.

They continue in milk for a long period. The best never go dry, and may
be milked even up to the time of calving, giving from eight to ten
quarts of milk a day. But even the best cows often fall short of the
quantity of milk which they are able to give, from being fed on food
which is too dry, or not sufficiently varied, or not rich enough in
nutritive qualities, or deficient in quantity.



The SECOND class is that of good cows; and to this belong the best
commonly found in the market and among the cow-feeders of cities.

They have the mammary part of the milk-mirror well developed, but the
perinean part contracted, or wholly wanting, as in cut G; or both parts
of the mirror are moderately developed, or slightly indented, as in cut
H. Cut E belongs also to this class, in the lower part; but it indicates
a cow, which--as the upper mirror, 1, indicates--dries up sooner when
again in calf.

These marks, though often seen in many good cows, should be considered
as certain only when the veins of the perineum form, under the skin, a
kind of network, which, without being very apparent, may be felt by a
pressure on them; when the milk-veins on the belly are well-developed,
though less knotty and less prominent than in cows of the first class;
in short, when the udder is well developed, and presents veins which are
sufficiently numerous, though not very large.

It is necessary here, as in the preceding class, to distrust cows in
which the mirror is not accompanied by large veins. This remark applies
especially to cows which have had several calves, and are in full milk.
They are medium or bad, let the milk-mirror be what it may, if the veins
of the belly are not large, and those of the udder apparent.

The general characteristics which depend on form and constitution
combine, less than in cows of the preceding class, the marks of good
health and excellent constitution with those of a gentle and feminine
look.

Small cows of this class give from seven to ten or eleven quarts of milk
a day, and the largest from thirteen to seventeen quarts. They can be
made to give three-fourths of a pint of milk, just after calving, for
every ten ounces of hay consumed, if well cared for, and fed in a manner
favorable to the secretion of milk.

They hold out long in milk, when they have no upper mirrors or tufts. At
seven or eight months in calf, they may give from five to eight quarts
of milk a day.

The THIRD class consists of middling cows. When the milk-mirror
really presents only the mammary or lower part slightly indicated or
developed, and the perinean part contracted, narrow, and irregular--as
in cut K--the cows are middling. The udder is slightly developed or
hard, and shrinks very little after milking. The veins of the perineum
are not apparent, and those which run along the lower side of the
abdomen are small, straight, and sometimes unequal. In this case the
mirror is not symmetrical, and the cow gives more milk on the side where
the vein is the largest.



These cows have large heads, and a thick, hard skin. Being ordinarily in
good condition, they are beautiful to look at, and seem to be well
formed. Many of them are nervous and restive, and not easily approached.

Cows of this class give, according to size, from three or four to ten
quarts of milk. They very rarely give, even in the most favorable
circumstances, half a pint of milk for every ten ounces of hay which
they consume. The milk diminishes rapidly, and dries up wholly the
fourth or fifth month in calf.

The FOURTH class is composed of bad cows. As they are commonly in
good condition, these cows are often the most beautiful of the herd and
in the markets. They have fleshy thighs, thick and hard skin, a large
and coarse neck and head, and horns large at the base.

The udder is hard, small and fleshy, with a skin covered with long,
rough hair. No veins are to be seen either on the perineum or the udder,
while those of the belly are slightly developed, and the mirrors are
ordinarily small, as in cut L.

With these characteristics, cows give only a few quarts of milk a day,
and dry up in a short time after calving. Some of them can scarcely
nourish their calves, even when they are properly cared for and well
fed.

Sickly habits, chronic affections of the digestive organs, the chest,
the womb, and the lacteal system, sometimes greatly affect the milk
secretion, and cause cows troubled with them to fall from the first or
second to the third, and sometimes to the fourth class.

Without pushing this method of judging of the good milking qualities of
cows into the objectionable extreme to which it was carried by its
originator, it may be safely asserted that the milk-mirror forms an
important additional mark or point for distinguishing good milkers; and
it may be laid down as a rule that, in the selection of milch cows, as
well as in the choice of young animals for breeders, the milk-mirror
should, by all means, be examined and considered; but that we should not
limit or confine ourselves exclusively to it, and that other and
long-known marks should be equally regarded.

There are cases, however, where a knowledge and careful examination of
the form and size of the mirror become of the highest importance. It is
well known that certain signs or marks of great milkers are developed,
only as the capacities of the animal herself are fully and completely
developed by age. The milk-veins, for instance, are never so large and
prominent in heifers and young cows as in old ones, and the same may be
said of the udder, and of the veins of the udder and perineum; all of
which it is of great importance to observe in the selection of milch
cows. Those signs, then, which in cows arrived at maturity are almost
sufficient in themselves to warrant a conclusion as to their merits as
milkers, are, to a great extent, wanting in younger animals, and
altogether in calves, as to which there is often doubt whether they
shall be raised; and here a knowledge of the form of the mirror is of
immense advantage, since it gives, at the outset and before any expense
is incurred, a somewhat reliable means of judging of the future milking
capacities of the animal; or, if a male, of the probability of his
transmitting milking qualities to his offspring.



It will be seen, from an examination of the points of a good milch cow
that, though the same marks which indicate the greatest milking
qualities may not always indicate the greatest aptitude to fatten, yet
that the signs which denote good fattening qualities are included among
the signs favorable to the production of milk; such as soundness of
constitution, marked by good organs of digestion and respiration
fineness and mellowness of the skin and hair, quietness of
disposition--which inclines the animal to rest and lie down while
chewing the cud--and other marks which are relied on by graziers in
selecting animals to fatten.

In buying dairy stock the farmer generally finds it for his interest to
select young heifers, as they give the promise of longer usefulness. But
it is often the case that older cows are selected with the design of
using them for the dairy for a limited period, and then feeding them for
the butcher. In either case, it is advisable, as a rule, to choose
animals in low or medium condition. The farmer cannot commonly afford to
buy fat; it is more properly his business to make it, and to have it to
sell. Good and well-marked cows in poor condition will rapidly gain in
flesh and products when removed to better pastures and higher keeping,
and they cost less in the original purchase.

It is, perhaps, superfluous to add that regard should be had to the
quality of the pasturage and keeping which a cow has previously had, as
compared with that to which she is to be subjected. The size of the
animal should also be considered with reference to the fertility of the
pastures into which she is to be put. Small or medium-sized animals
accommodate themselves to ordinary pastures far better than large ones.
Where a very large cow will do well, two small ones will usually do
better; while the large animal might fail entirely where two small ones
would do well. It is better to have the whole herd, so far as may be,
uniform in size; for, if they vary greatly, some may get more than they
need, and others will not have enough. This, however, cannot always be
brought about.





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Previous: Points Of A Good Cow



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