BLEEDING.
The common mode of drawing blood from the pig is by cutting off portions of the ears or tail; this should only be resorted to when local and instant blood-letting is requisite. The jugular veins of swine lie too deep, and are too much imbedded in fat to admit of their being raised by any ligature about the neck; it is, therefore, useless to attempt to puncture them, as it would only be striking at random.
Those veins, however, which run over the interior surface of the ear, and especially toward its outer edge, may be opened without much difficulty; if the ear is turned back on the poll, one or more of them may easily be made sufficiently prominent to admit of its being punctured by pressing the fingers on the base of the ear, near to the conch. When the necessary quantity of blood has been obtained, the finger may be raised, and it will cease to flow.
The palate veins, running on either side of the roof of the mouth, are also easily opened by making two incisions, one on each side of the palate, about half way between the centre of the roof of the mouth and the teeth. The flow of blood may be readily stopped by means of a pledget of tow and a string, as in bleeding the horse.
The brachial vein of the fore-leg—commonly called the plate-vein—running along the inner side under the skin affords a good opportunity. The best place for puncturing it is about an inch above the knee, and scarcely half an inch backward from the radius, or the bone of the fore-arm. No danger need to be apprehended from cutting two or three times, if sufficient blood cannot be obtained at once. This vein will become easily discernible if a ligature is tied firmly around the leg, just below the shoulder.
This operation should always be performed with the lancet, if possible. In cases of urgent haste, where no lancet is at hand, a small penknife may be used; but the fleam is a dangerous and objectionable instrument.