Part 8

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.