This affection is occasionally met with in canine practice. It is due to a parasite identical with that in favus, and is the exciting element in both diseases. The same influences are active in propagating all forms of vegetable parasites or fungi; warmth and moisture favor them, and thus damp kennels, unclean bedding, and general neglect are predisposing causes.

Ringworm is very easily communicated by contact; animals may transmit the affection to man or by turn be infected. The disease manifests itself in round patches which are covered with thin scales or crusts easily detached. It spreads quite uniformly, enlarging its circle on the outer edge of which the eruption is more prominent, receding as it were from the centre. The hair becomes dry and harsh, losing its elasticity and breaks off or falls out.

Ringworm may appear in the form of small pointed vesicles, containing a clear fluid, and arranged in a circular form; or it may take the form of pale, red spots, having a small whitish scale in their centre.

Treatment

The destruction of the parasite which excites the disease ought not be difficult. The hair should be shaved sufficiently beyond the eruption to insure all affected parts are exposed; then crusts are to be removed by soaking with oil or lard, after which the animal should be thoroughly washed in strong soap suds.

The local applications advised are numberless; among the more efficient are the black wash, tincture of iodine, and balsam of peru. A very successful method is to paint the spots well every two days for a week with the tincture of iodine, applying several coats at each operation; on the intervening days, and after the week has passed, a preparation of carbolic acid grains twenty, oxide of zinc ointment one ounce, should be used.

If the ringworm has existed a long time and the parts are infiltrated, the oil of tar should be applied after the parasite has been destroyed, and may be combined with glycerin, one part to three. Only a short time will be needed to effect a cure. After exposure of an animal to the disease, from one to two weeks is required for its development.