It was first described in 1835 by Kégélaar, and has been the subject of investigation by Hering, Gerlach, Delafond, and Mégnin.
Causation. It is produced by the Chorioptes bovis, and is transferred with difficulty, even by cohabitation.
Symptoms. This form of mange in the ox does not affect the same parts as in other animals. In the horse, etc., it attacks the limbs, whilst in the bovine species it is usually found at the base of the tail. It causes slight itching. The diseased region becomes covered with numerous little pellicles, the hairs gradually fall, crusts form, and the skin shows deep cracks. When the disease is completely neglected, it may extend to the loins, back, sides of the body and shoulders. It may also affect the perineal region, the inner surface of the thighs, and in fact the whole of the body if the animals are young and in poor condition.
Diagnosis. At the outset it is difficult to distinguish between chorioptic and psoroptic mange, and the use of the microscope is necessary. On a superficial examination chorioptic mange may be mistaken for phthiriasis when the latter attacks the posterior portions of the body, particularly the base of the tail, and when it is accompanied by eruptions, loss of hair, and intense itching.
The distinction between the two conditions, however, is extremely easy after an examination of the two parasites.
Prognosis. The disease is of slight gravity, and does not threaten the animal’s health unless neglected for so long a time that the parasites invade all parts of the body. In that case the disease may cause anæmia and loss of condition.
The treatment of this form of mange comprises nothing special, it being sufficient to proceed as directed in the previous article.
The stables ought always to be thoroughly disinfected.
MANGE IN THE GOAT.
The goat suffers from the attacks of sarcoptes, psoroptes, and chorioptes, but up to the present time only two forms of mange have been described, sarcoptic and chorioptic mange.