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of this plant in the early spring months when all feed was scarce, but 

 the recorded losses have not been large. 



Symptoms of Poisoning by the Showy Milkweed. 



The symptoms of poisoning were quite different from those produced 

 by the narrow-leaved milkweed. The first symptom noted was extreme 

 dullness, with a total loss of appetite and a tendency to lie down. In 

 the severe cases the breathing was distinctly irregular, the breath being 

 expelled with a grunt. Spasms were entirely absent and in the 

 whole series symptoms seemed much unlike those produced by the 

 narrow-leaved milkweed. 



Typical Cases 



Case No. 1 On September 6, 1918, at 2 p. m. a yearling range lamb 

 weighing 85 pounds was fed 2 pounds of the fresh green leaves. At 

 8 a. m. the next day it showed symptoms of poisoning. During the day 

 of September 9 it was still sick. September 10 it appeared to have 

 recovered. 



Case No. 2 September 6, 1918, at 11 : 30 a. m. a ewe weighing 94 

 pounds was fed 2J pounds of green pods. She was sick by 6 p. m. the 

 same day. At 9 : 30 she was down ; the breathing was labored and 

 grunting. No other .symptoms were, exhibited. The next morning at 

 8 a. m. she was found dead. 



Case No. 3 September 12, 1918, at 4 p. m. a yearling lamb weighing 

 81 pounds was fed one-half pound of seeds. At 7 p. m. of the same 

 day it was extremely dull, respiration irregular. At 8 : 30 p. m. it was 

 much worse ; the breathing was more labored and each breath was 

 made with a peculiar grunt. At 10 p. m. the animal was dead. 



Heart-Leaved Milkweed (Asclepias cordifolia). 



This plant is not abundantly distributed in the fields or ranges of 

 Nevada. It occurs only in the mountain valleys, and does not appear 

 to be poisonous. 



Five feedings of this milkweed were made to sheep, the amounts fed 

 ranging from one-half pound to 2| pounds. None of the feedings so 

 far as could be observed had any poisonous effect upon the animal. 



This milkweed can be distinguished from the- showy milkweed by 

 its surface being smooth or free from hairs, while the showy milkweed 

 is covered with fine hairs. The base of the leaf is heart-shaped, which 

 is not the case with the showy milkweed. There is little danger of con- 

 fusing it with the narrow-leaved milkweed. 



Prostrate Milkweed (Asclepias cryptoceras). 



This species of milkweed is not important as a poisonous plant. It 

 grows sparingly and is not widely distributed. It is a plant with 

 somewhat tough leathery leaves, and its growth habit tends to be close 

 to the ground. It may be disregarded as a poisonous plant of any 

 importance in Nevada. One feeding of 3 pounds at one time was made 

 to a mature sheep which did not seem to be at all injured by this large 

 amount. 



