12 BULLETIN 110, U. S. DEPARTMENT OF AGRICULTURE. 



occur after a considerable delay also adds a doubtful factor to the 

 determination of the dosage. The experiments with calf Xo. 122 in 

 1911 indicated that the toxic dose was not far from 1 gram, or 

 0.0022 pound, per pound of animal weight : or. put in another way, 

 a 1.000-pound bovine would probably be poisoned by 2.2 pounds 

 of the plant. The experiments with cattle in 1912 and 1914 served 

 to confirm this general conclusion, and it seems probable that the 

 toxic dose for a bovine weighing 1.000 pounds is not far from 2 

 pounds. 



In the case of the sheep, symptoms were produced by 0.061 pound 

 per 100 pounds of animal, and death was produced by 0.330 pound. 

 Inasmuch as sheep Xo. 283 was sick and recovered from 0.219 pound, 

 the lethal dose is somewhere between that figure and 0.330 pound. 

 The large dosage received by sheep Xo. 228 on April 3 and 4 was 

 distributed over two days with consequently less effect. In general, 

 while too much reliance must not be placed on the results of a few 

 experiments, it may be said that sheep may be poisoned by 0.06 

 pound, and fatal results may occur from a quantity between one- 

 quarter and one-half of a pound. It will be noticed that, in terms 

 of a ratio to body weight, the dosage for cattle and sheep is very 

 nearly the same. 



While the number of cases is small and there are a number of fac- 

 tors that throw doubt on the results, such as the varying conditions 

 of the animals, the varying length of time in the feedings, etc., never- 

 theless the results may be considered as indicating approximately 

 both the toxic and the lethal dose. 



It appears to be probable from these experiments that Chrosperma 

 is much more poisonous than the Zygadenus which causes such heavy 

 losses of sheep in the West. 



SYMPTOMS. 



/Salivation, — This is the first symptom noticed. The animal ceases 

 eating and there is frothing at the mouth in a marked degree. 



Nausea, — There are pronounced symptoms of nausea, which is fol- 

 lowed in severe cases by profuse vomiting. 



Pulse. — The pulse during most of the illness is nearly normal, al- 

 though it may be somewhat rapid in the more acute stages of the 

 intoxication. 



Respiration,- — The respiration is rather more rapid than normal 

 and is frequently labored and irregular. 



Temperature. — There is not much change in temperature, but it is 

 liable to be slightly lower than normal. 



Weakness. — The animal becomes very weak and staggers when it 

 attempts to walk. When walking it moves in a stiff-legged manner. 



Autopsy. — The autopsy findings indicate that in the organs there 

 is little change which can be considered typical of the disease. 



