WHITE LOCO WEED. 95 



stated, becomes more and more emaciated and crazy. One of the fre- 

 quent effects of this habit is the shedding of the fleece as a whole or 

 in patches. The animal becomes unable to take care of itself and, 

 unless carefully watched, is apt to fall into the water and be drowned 

 while attempting to drink. The sight becomes more and more 

 affected until the animal is unable to direct its course properly or to 

 keep along with the band. Fits of trembling are of frequent occur- 

 rence during the later stages of the disease, and finally the animal 

 dies from inadequate nutrition and total exhaustion as the result of 

 the muscular convulsions. 



In chronic cases of loco disease in horses the animal is usually left 

 to its own resources on the range. During the later stages it loses to 

 a large degree the power of locomotion and remains for two or three 

 weeks at a time upon a small area of ground. We have had the 

 opportunity of observing a number of such cases in horses which 

 were almost unable to walk. Under these circumstances the animals 

 seldom or never lie down, and it ma}" be doubted whether they could 

 get up if they once should lie down. One horse which was under con- 

 tinuous observation for a period of two weeks in 1897 remained dur- 

 ing this time upon a piece of ground about 150 feet square. The 

 ground and vegetation were unusually dry, and the horse had no water 

 during the two weeks. At the end of this time the animal walked 

 about 1 mile to a small stream where, in attempting to drink, it fell 

 and was unable to get upon its feet again. It seems very difficult to 

 understand how, under the dry conditions of the open plain, animals 

 can live so long without water. 



Numerous autopsies made on locoed sheep and horses revealed con- 

 ditions which, though fairly uniform, did not constitute a well-defined 

 series. Naturally the post-mortem findings in case of animals allowed 

 to die a natural death from the loco disease will differ from those of 

 animals which are killed and bled before being examined. As stated 

 in the description of the symptoms, locoed animals usuall}" die in more 

 or less violent spasms. As a result of these spasms the blood is found 

 after death unevenly distributed in the blood vessels. The lungs are 

 frequently found to be congested for the reason that the blood was 

 inadecjuately aerated at the time of death. We made a large number 

 of post-mortem examinations upon bodies of locoed sheep which had 

 been killed and bled immediately before examination. In these cases 

 there was no lesion or marked changes in the alimentary tract. A 

 slight congestion of the membranes of the brain was to be observed 

 in all cases. The lungs and heart were apparently not affected. The 

 voluntary muscles were of a paler color than under normal conditions, 

 and the fat tissue was considerably reduced in quantity. 



Undoubtedly a serious mistake has been made by a majority of sheep 

 men who have suffered losses from the loco disease in allqwing the 



