32 
BULLETIN 947, U. S. DEPARTMENT OF AGRICULTURE. 
Comparing these results with those in Table 8, showing the effect 
of feeding green leaves in the corrals, it is interesting to note that the 
average quantity, about 2.5 pounds, necessary to produce acute 
cases, is only slightly greater than the average quantity, fed in the 
corrals for three weeks, which produced chronic cases — namely, 2.2 
pounds. While as large a quantity as 3.143 pounds has been fed 
daily for 22 days before producing intoxication, it is evident that 
when the feeding is not made in a single dose, but is continuous and 
spread over a considerable period of time, much of the toxic principle 
must be eliminated. 
Continued Forced Feeding. 
In some animals the forced feeding of green leaves was continued in 
smaller doses for several days. The following table shows those in 
which positive results were obtained: 
Table 7. — Forced feedings of green leaves, in two or more days, which -produced intoxi- 
cation. 
Animal. 
1915. 
Sheep 355 
Sheep 358 
Sheep 327 
Average 
Davs 
fed. 
Days. 
3 
3 
Number 
of feed- 
ings. 
Quantity fed per hundredweight of 
animal. 
Total. 
Pounds. 
4.001 
4.139 
7. 936 
5. 359 
Daily 
average. 
Pounds. 
1.33 
1.379 
1.134 
1.2S1 
Result. 
Died. 
Sick. 
Do. 
According to Table 7, an average daily feeding of 1.281 pounds 
continued for 4J days produced sickness or death, or, in round num- 
bers, 1J pounds given daily for 4 or 5 days produced intoxication. 
As compared with voluntary feeding upon leaves (p. 33) these force- 
fed animals were poisoned on a smaller dosage and in less time. 
TOXICITY OF LEAVES OF PLANT. 
It is to be presumed that sheep on the range, when eating H. 
hoopesii feed mainly on the leaves. It is of special interest, therefore, 
to know the dosage of leaves that will produce sickness or death. A 
large number of feeding experiments were carried on, and Table 8 
summarizes the results of corral feeding of green leaves. 
