WHITE LOCO WEED. 93 



was again tried with much better success. The spasms became less 

 pronounced and the ewes recovered on the second day. The lambs, 

 however, had died in the meantime from the poison contained in the 

 milk of the mother. The lambs in these three cases were two weeks 

 old and had not eaten loco weed or an}" other plants. 



SYMPTOMS OF POISONING. 



The symptoms of loco disease in animals are familiar to all stock 

 raisers. Perhaps the most characteristic are those of cerebral origin, 

 consisting in peculiar irregularities in gait and action, which may be 

 compared to a drunken condition in men. Sheep and other animals 

 affected by this disease are commonly said to be crazy or locoed. The 

 cerebral disturbance may consist in an impairment of the function of 

 the special senses, or in improperly regulated motor impulses which 

 produce a more or less pronounced incoordination of muscular move- 

 ment. Sight is frequently much impaired. In some cases the animal 

 soon becomes totally blind. This condition is reached more often in 

 acute cases than in chronic cases of loco disease. More frequently the 

 animal simply sees incorrectly or makes errors in judgment of size or 

 distance of objects. These errors in judgment of ocular perceptions 

 are a common occurrence and are often so pronounced as to become 

 ludicrous. A locoed horse upon being driven up to a gate ma}" either 

 attempt to jump over the crossbar, which is usually placed at the 

 height of about 15 feet, or may lower his head from fear of striking 

 it. Simple experiments indicate that both sheep and horses in a locoed 

 condition frequently mistake harmless things for dangerous enemies. 

 In horses which are affected with the chronic form of loco disease one 

 has abundant opportunity to observe many peculiar and senseless 

 actions which are evidently due to cerebral disease. Locoed horses 

 are often used for both draft and driving purposes. Such horses may 

 work or travel in a perfectly normal manner for days at a time. They 

 frequently, however, run away or aie attacked with kicking fits with- 

 out any apparent external cause. Observations made on horses which 

 are only slightly locoed indicate that they do at times become fright- 

 ened by purely imaginary objects. This fright would seem, however, 

 to be none the less real, since such horses often tremble or become 

 covered with a cold sweat after these imaginary dangers are passed. 



The sense of hearing is frequently affected in locoed animals, as is 

 easily demonstrated by simple experiments. The respoinse to various 

 sounds and noises is not always in accordance with the character or 

 volume of the sound. At times a loud noise is unheeded, while at 

 other times a slight noise of the same character may produce fright. 

 The locoed animals are often unable to judge correctly the direction 

 from which sounds come. 



Irregularities of the muscular movements of locoed animals may 



