LOCOWEED DISEASE OF SHEEP 395 



Jacob Hayem sent from his ranch two sheep which he said were badly locoed. 

 The animals were thin and weak, weighing 25 and 35 pounds respectively. The 

 fleece was good, there was no cough nor nasal discharge. There was only slight 

 stiffness in gait. The incisor teeth were unusually long and widely separated. The 

 field note was made that these animals did not present the usual appearance of the 

 so-called "typical locoes" but would pass for specimens of poor stock which might 

 improve if properly cared for during the winter. Compared with the experimental 

 locoes they were pretty healthy looking animals. 



Autopsy ^7. At autopsy the smaller animal showed only a very large mass of 

 tape-worm in the middle three-fourths of the small intestine. A field examination 

 indicated that these worms were Taenia expansa. 



Autopsy $8. The game tape-worm {Taenia expansa) was found in large numbers 

 in the intestine of the second sheep in which also the bile ducts contained Thysano- 

 soma actinioides. There was also infection with the Oestrus ovis together with ab- 

 scesses in the lung. 



Autopsy 29. August 31. The third sheep from Forsyth, a two year old, had been 

 kept in camp for observation for several days. It appeared rather worse than either 

 of the other two (Autopsy 23 and Autopsy 24), and was very thin. It was, however, 

 active, alert, and free from stiffness. It coughed and sneezed very little, did not pre- 

 sent the symptoms popularly attributed to the so-called typical loco, showing no twitch- 

 ings, and having no tremor nor any special nervous symptoms. Hemoglobin 70 per 

 cent by the Tallquist scale, temperature 102°, respiration 16 to the minute, pulse 116. 

 At autopsy it was found to be infected with Thysanosoma actinioides causing dilata- 

 tion and thickening of the bile ducts. There was Oestrus ovis inflammation to a slight 

 degree and small wire worms were found in the fourth stomach. Cysticercus tenui- 

 collis occurred in the peritoneal cavity. The animal was moderately emaciated. 



The eighteen cases described above came from different ranches which 

 were not very close together; the ranchmen were men of experience in 

 sheep raising, and considered themselves, and were considered by their 

 neighbors fully qualified to recognize loco disease. These ranchmen selected 

 from bands of sheep containing many invalids the most typical and pro- 

 nounced cases of loco disease, and turned them over to' me for study. It 

 seems hardly possible that every one of the ranchmen could have fallen 

 into the error of selecting for me invalid sheep which more experienced 

 sheepmen would not have looked upon as locoes. In fact, several oppor- 

 tunities arose to check up the diagnosis of one ranchman by that of another, 

 and only minor differences existed between them. It is, then, reasonable 

 to assume that the ranchmen made few, or no, errors of diagnosis, and 

 that the sheep examined were fairly typical representatives of the armies of 

 locoed sheep in Montana. A study of these sheep ought to reveal the symp- 

 toms characteristic of locoweed poisoning, and the autopsies should bring 

 to light any striking anatomical changes produced by the use of the weed if 

 such occur. It must be stated at once that neither of these objects could be 

 accomplished. 



