TEXAS FEVER. 
Ill 
SUMMARY AND CONCLUSIONS. (TICK-INFESTATION.) 
It will be seen from the history of the above 21 head of 
young cattle that but one died from an acute attack of the fever 
within the usual period of 12 to 20 days following tick-infesta¬ 
tion, and that this one, No. 6, a two months old calf, was pur¬ 
posely infested with an excessively large number of ticks. The 
first crop of ticks matured on all the other cattle, and but few 
of the animals showed any distressing symptoms of the fever. 
The yearlings that were mildly or intermittently infested the 
first season did not suffer the profound nutritive disturbances 
noted in others that were grossly and continuously infested. 
(Contrast steers No. 1 and 5 with steers No. 2, 3 and 4, all in¬ 
fested in 1897.) Young calves, from 2 to 6 weeks old, infested 
mildly in the fall, suffered but little from the infestation, but 
were not fully immunized against the effects of gross infestation 
the following year, after being free from ticks for seven months. 
Bull No. 10 died from relapse in the fall of 2d season (1898), 
and No. 19 was quite ill his second season (1899), and others of 
the 1899 group while apparently in good health showed consid¬ 
erable destruction of blood corpuscles. An acute fatal relapse 
occurred in two animals (Nos. 10 and 14) following gross second¬ 
ary infestation ; both had matured ticks earlier in the same sea¬ 
son and one (No. 10 mentioned above) had carried ripe ticks the 
previous fall. Lack of proper nourishment and a concurrent 
disease are to be regarded as contributing largely to these re¬ 
lapses. 
Animals that had been well infested with the fever ticks at 
the north, proved immune when exposed to the more prolonged 
infestation occurring at the south. 
Five head of the experiment animals died from other causes 
than Texas fever. Jersey bull calves from the dairy herd were 
mainly used in the experiments. They were taken from the 
mother quite young and fed by hand. Their care through the 
winter was such as is given ordinary stock cattle, and not that 
which is given to breeding animals intended for sale. These 
losses, largely preventable, would probably not have been so 
