STOCK-POISONING PLANTS OP TPIE EANGE. 
19 
to be the cause of many deaths of cattle. While very little experi- 
mental work has been done upon it, it has been shown to be poison- 
ous, and should be avoided. 
Other Possible Loco Plants. 
Popularly all plants resembling the locoes are called locoes. As 
shown on page 16, some of these are known to be harmless. On 
the other hand, there is good reason to think there are still a number 
of true locoes which have not yet been recognized. It is an inter- 
esting fact, too, that some of the plants closely related to the loco 
plants are distinctly poisonous to livestock, although they do not 
produce true loco symptoms. 
Symptoms of Loco Poisoning. 
All the loco plants produce similar effects. These symptoms 
appear only after a somewhat prolonged feeding upon the plant, and 
this fact has led to the 
failure of a great many 
feeding experiments 
with loco. Ordinarily 
the first symptom in a 
locoed animal is a loss 
of condition. This is 
followed by irregulari- 
ties of gait and weak- 
ness which in many 
cases seems almost to 
amount to paralysis. 
The animal shows a 
lack of coordination in 
its m uscula r move- 
ments, due without 
doubt to the effect of 
the plant upon the cen- 
tral nervous system. 
Horses formerly gentle 
become uncontrollable and shy violently at imaginary objects or leap 
high over some slight obstruction. Generally speaking, a locoed 
horse can be neither led nor backed, and when put in motion can not 
easily be stopped or turned, but may continue until it runs against a 
fence or other obstruction. 
Many animals acquire a liking for the plant to such an extent that 
they will eat nothing else. This, however, is not true in all cases. 
The animal, when affected, shows progressive emaciation and even- 
tually starves to death. It is not at all unusual in a country where 
there are locoed cattle to see a steer standing off by itself, sometimes 
remaining in one position for hours, or even for days, and finally 
falling and dying without making any attempt to go elsewhere 
for either food or water. 
In Figure 14 is shown a steer poisoned by the blue loco. Figure 
15 is a picture of a steer in the last stages of loco poisoning from 
eating white loco. Figure 16 is a locoed range horse, probably 
affected by the blue loco. In Figure 17 are shown two horses 
Fig, 14. 
A steer poisoned by the blue loco (Astragalm 
Mphysus) . 
