1. Horses when grazing are free from all diseases except podagra; from this they suffer, and sometimes lose their hoofs, which grow again as soon as they are lost, and the loss of the hoof usually takes place as soon as the first recommences its growth. It is a sign of the disease when the right testicle throbs, or when a wrinkled hollow place appears a little below the middle of the nose. Horses that are brought up in a domestic state suffer from several other diseases; they are attacked with a disorder in their bowels, and it is a sign of the disease when they drag their hind legs up to their fore legs, and keep them under in such a way that they almost strike together: if they go mad after having abstained from food for several days, they are relieved by bleeding and castration.[218]
2. The tetanus is another disease of horses, which is thus recognised; all the veins, and the head and neck are extended, and their legs are stiff when they walk; the horses also become full of corrupt matter. They are also attacked by another disease in which they are said to have the crithia;[219] the softness of the roof of the mouth, and heated breath, are the signs of this disease, which is incurable, unless it stays of its own accord. Another disease is called nymphia,[220] which is relieved by the sound of a flute; it causes them to hang down their heads, and when anyone mounts they rush forward until they run against something. The horse is always dejected if afflicted with madness; this is a sign of it, if it lays down its ears upon its mane, and then draws them forward, and pants and breathes hard.
3. These also are incurable if the heart is affected. It is a sign of this disease if the animal suffers from relaxation. And if the bladder alters its position, difficulty in making water is a sign of this disease; it draws up the hoofs and loins. It is also fatal for the horse to swallow the staphilinus, which is of the same size as the spondyla. The bite of the shrew mouse is injurious to other animals also; it causes sores, which are more severe if the creature is pregnant when it bites, for the sores then break. If they are not pregnant, the animal does not perish. The creature called chalkis by some persons and zygnis by others, inflicts either a fatal or very painful bite. It resembles a small lizard, and is of the same colour as the serpent called the blind worm.
4. And, on the whole, those who understand horses say that both these animals and sheep suffer from all the infirmities with which mankind is afflicted. The horse, and every other beast of burden, is destroyed by the poison of sandarach.[221] It is dissolved in water and strained. The pregnant mare casts her young with the smell of a lamp going out. This also happens to some pregnant women. This is the nature of the diseases of horses.
5. The hippomanes, as it is called, is said to be produced upon the foals; the mares when they have bitten it off lick the foal and cleanse it. The fables on this subject have been invented by women and charmers. It is, however, agreed that mares before parturition eject the substance called polion.
6. Horses recognise again the voices of any with which they may have fought. They delight in meadows and marshes, and drink dirty water; and if it is clean, they first disturb it with their hoof, and then drink and wash themselves. And on the whole, the horse is an animal fond of water, and still more fond of moisture; wherefore, also, the nature of the river-horse is thus constituted. In this respect the ox is very different from the horse, for it will not drink unless the water is clean, cold, and unmixed.