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The Bulletin 
if judged in the light of experiments with sheep to be presented later, 
are equally true and interesting. He says: “Many animals may feed 
on the same lands and evidently partake about equally of the poison 
and some of them suffer violently and die; others suffer lightly and 
recover, and others still, perhaps the larger number, remain quite 
healthy.” 
b. In Sheep .—Very little that is distinctive can be gathered from the 
published accounts of the symptoms of the disease in other domestic 
animals. Writers have largely resorted to the use of the expression 
“similar to those of the disease in cattle” in describing the symptoms. 
The only clinical account of the disease in sheep which has come to 
our attention is that given by Jordan and Harris (1909) from observa¬ 
tions made by D. D. Todd upon two ten weeks’ old lambs. Both of 
these animals were lying down when found, and one made no attempt to 
rise, while the other kept its feet going in a walking motion with each 
unsuccessful effort to get up. Respiration was regular in both animals 
but forced and jerky in the case of one lamb. USTo sign of pain was evi¬ 
dent, but occasionally one animal ground its teeth. 
In the present studies in sheep considerable individual variation has 
been found to exist, both in the period elapsing until the initial symp¬ 
toms of trembles are apparent and in the period following until death 
ensues. During the season of 1916 some were sick as early as three 
days after being placed on the experiment, and no ill effects were ap¬ 
parent for three weeks in other cases. During the present season (1917) 
one animal became sick on the second day and died within forty-eight 
hours after feeding was begun. Others remained apparently normal 
for about twelve weeks before contracting the disease. Sheep usually 
live three or four days after the disorder is first noticed, but some have 
been observed to die within twelve hours. Only one sheep characteris¬ 
tically affected entirely recovered and the feeding of white snakeroot 
to this animal was discontinued as soon as trembling was noted. 
One of the first signs of the onset of the disease is a loss of appetite 
and gritting of the teeth. Such animals are sluggish and manifest a 
marked disinclination to move. They may remain standing in a droopy 
posture (Big. A) or may be quiet in a normal resting position. Respira¬ 
tions are accelerated, often jerky and somewhat labored. A marked 
stiffness of the legs and ataxia characterize the movements in walking. 
This is manifest early and becomes more aggravated as the disease pro¬ 
gresses. If after a day or two, the animal is urged to rise and is driven 
a few yards, muscular spasm, especially in the limbs, is evident. The 
sheep then refuses to move, stands with hind limbs placed well under 
the body (Figs. A and B) and all feet spread apart laterally. In this 
