tag="{http://www.w3.org/1999/xhtml}a">[50]

All of Nockolds’s animals which were locoed were mares more than 6 years of age.[51]

According to Stalker there is a passive type in which the animal shows symptoms only on being disturbed; the animal then becomes unmanageable. This happens even with old, well-broken saddle horses.[52]

There are few published reports as to the symptoms occurring in sheep which are locoed. Stalker[53] says sheep “become loco-eaters, grow stupid, emaciated, and eventually die.” One of the few descriptions of the symptoms is that of Ruedi,[54] in which he claims that the symptoms in sheep are those comparable to the symptoms of cerebro-spinal meningitis except that there is an absence of fever. Ruedi speaks of sheep “lying flat on the ground, not able to stand, and not able even to lift their heads to drink the offered water; the head and the vertebra in opisthotonus position; the four legs stretched out and stiff; breathing was stertorous, pulse slow, abdomen much distended, diarrhea present. * * * The heart * * * was very slow and insufficient.” The teeth (in sheep) may blacken and fall out.[55]

It is mainly the young animals, such as lambs and colts, that are affected, probably due to the fact that their attention is more easily directed to the flower of the loco[56] plants. It is claimed (on slight evidence) that men have become locoed. The symptoms in them are nausea and headache.[57]

Schuchardt[58] has called attention to the resemblance of the symptoms in locoed animals to those which occur in so-called lathyrism, but most observers in this country have especially marked the resemblance of the symptoms to those induced by the habitual use of narcotic drugs.[59]

As a rule the loco plants are refused by animals save when there is lack of other food, although at times animals have shown the keenest relish for these plants, rejected all other forage, and devoted their whole attention to searching for the loco plants.[60]

Stalker says that animals not too long addicted to the use of these plants, if confined, soon lose their taste for them (after two or three months),[61] although old loco eaters do not readily lose the habit. Stalker also says that “it is to be presumed that the plant is possessed of some toxic property that has a specific effect on the nervous centers, and that these effects have a marked tendency to remain permanent.”[62]

The fundamental character of the disorder seems to be a progressing anæmia. The interpretation of psychical symptoms in herbivora, and especially on the range, must often be fallacious.