An animal with the wound thus open at the coronet, and freely discharging its contents, may, if no serious complications exist, walk tolerably sound.  It is only when put to the trot that symptoms of lameness are apparent.

It may so happen, however, that we first see the case when the symptoms are wholly those arising from a painful suppuration within the horny box.  This occurs when the original injury has taken place at a more dependent position than the coronet.  Either from violent blows upon the hoof, puncture from below, from corn or from sand-crack, or any other causes we have enumerated, suppuration is occurring deeply within the hoof, with as yet no opening upon the coronet.

Even when an opening has already occurred on the coronet, the same condition of sub-horny suppuration may be met with in cases when the opening of the fistula has by some means or other become occluded.  Granulation tissue, for instance, may have temporarily closed the mouth of the fistula.  The pus, instead of continuing its discharge thereat, is made to burrow in other directions.

In either of these cases pain is excessive, the animal walks on three legs, the foot is painful to percussion, and grave constitutional disturbance is noticeable.  The presence of pus is immediately suspected, and, in the absence of any indication of an opening having existed at the coronet, searched for at the sole.  It may or may not be found.  If found it is given exit, and the case ends as one of ordinary pricked foot, of suppurating corn, or some other condition equally simple when compared with quittor.  In those cases where the pus is not discovered at the sole, one adopts the expectant treatment of poulticing.  This, if pus is present, is followed by a painful swelling of the coronet.  At one point there forms a hot and tender enlargement, with the hairs on it standing straight up from the skin, which latter is seen below red and inflamed in appearance.

Later, the abscess—­for abscess it is—­discharges its contents, the opening is explored, and we find that in extent it is not confined to the coronary region, but that it is deep enough to constitute a true sub-horny quittor.

This discharge of the abscess contents may take place at a well-defined spot on the coronet, or it may ooze out at the junction of the wall with the skin.  In appearance the discharged pus varies.  When the softer structures only are attacked it is thick, and yellow or white in colour; when bone is involved it is ichorous; and when attacking the horn itself black or gray.  It may or may not be extremely foetid, and often it is mingled with blood.

When evidence of a previous opening upon the coronet is plain, then it is not considered wise to attempt a paring of the sole.  Instead, poulticing is at once resorted to, to induce the discharge of the pus through its original channel.  Once this has occurred a fistulous wound remains, which is open for treatment upon one or other of the lines we shall afterwards indicate.