30 



BULLETIN 94*7, U. S. DEPARTMENT OF AGRICULTURE. 



ble, however, that to be absorbed in the rumen or reticulum it must 

 be in sufficient concentration to damage the epithelium. 



TOXIC DOSE FOR SHEEP. 



In determining the toxic dose a distinction should be made between 

 poisoning by a single administration of the plant and the toxic result 

 of prolonged feeding. It was found that no animal would eat enough 

 in a single day to produce symptoms, but by the use of the balling 

 gun it could be compelled to swallow enough to produce intoxication 

 or death. Moreover, the whole aerial part of the plant including 

 stems, leaves, and flowers was used with some animals while in other 

 cases use was made of stem leaves, radical leaves, flowers or sterns, 

 leaves, and fruit. 



Toxic dose of whole plant, including leaves, stems, and flowers when 

 fed. — Eight sheep were used in the feeding of the whole plant in 1915 

 and two in 1916. Table 5 shows the result: 



Table 5. — Summary of feedings of leaves, stems, and flowers. 



Animal. 



Total 

 fed per 

 hundred- 

 weight 



of 

 animal. 



Total 

 days 

 fed. 



Average 



daily 

 feed per 

 hundred- 

 weight 



of 

 animal. 



Days 

 before 

 sick. 



Quan- 

 tity per 

 hundred- 

 weight 



of 

 animal 



to 

 produce 

 sickness. 



Daily 

 average 



to 

 produce 

 sickness. 



Result. 



Sheep 316. 



1915. 



Pounds. 



2.19 

 82. 468 

 43. 299 

 74. 713 

 32. 865 

 28. 372 



2.469 

 80. 311 



Days. 



1 

 21 

 28 

 19 

 17 

 24 



3 

 59 



Pound. 

 2.19 

 3.9 

 1..546 

 3.932 

 1. 933 

 2.182 

 .835 

 1.361 



Days. 



Pounds. 



Pounds. 





Sheep 319 



21 



75.3 



3.1 



Died. 



Sheep 326 





Sheep 328 



19 



74. 713 



3.9 



Sick. 



Sheep 329 





Sheep 333 



24 



28. 372 



1.182 



Weak. 



Sheep 344 





Sheep 346 



23 



35.7 



1.5 



Symptoms. 



Sheep 386. 



1916. 



77. 166 

 49. 074 



52 

 36 



1.434 

 1.363 



20 

 23 



37. 579 

 34. 626 



1.879 

 1.505 



Sheep 385 



Do. 

















21.6 



47. 715 



2.17 

















In all the cases of 1915 except sheep 310 the animals were given 

 only the H. hoopesii. In the cases of 191 6, hay was fed with the plant. 



Averaging these cases, a daily feeding of 2.17 pounds continued 

 21 .6 days produced sickness or death. The limits of the daily dosage, 

 however, were rather wide, varying from 1.18 pounds in Sheep 333 to 

 3.9 pounds in Sheep 328. There was nothing in the conditions of 

 the experiments to explain this wide divergence. 



TOXIC DOSE FOR CATTLE. 



Cattle 824 was made sick in 21 days, receiving in that time 52.6 

 pounds while Cattle 827 was made sick in 39 days, receiving in that 

 time 48.32 pounds. The two cases average in 30 days of feeding with 



