10 THE STABLE FLY. 
with the weakened condition brought about by the loss of blood, 
however, an acute form of Texas fever is induced. When animals 
begin to suffer from the fever they are less energetic in fighting the 
flies and consequently become the more ready victims. During the 
outbreak in 1912 acute Texas fever was certainly produced as a result 
of fly attack. Owing to the continual biting of the insect the fever 
could not be reduced in many cases and the animals speedily died. 
During severe outbreaks the loss brought about by the reduction 
of the milk supply in fly-infested zones is an important item. In the 
1912 outbreak many dairymen found that their output of milk was 
reduced from 40 to 60 per cent, and that in some cases cows were 
completely dried up. For several months after the pest had abated, 
the effects of the outbreak were apparent in the reduced milk produc- 
tion. Even in cows which freshened several months after the pest 
had abated, the effect on milk yield was said to be still apparent. 
During 1912 all animals in the fly zone were greatly reduced in 
flesh. Cattle which were fat enough for market in many cases were so 
much reduced that they could not be sold. Horses and mules in 
many cases lost from 10 to 15 per cent in weight during the outbreak. 
Some dairy herds which were usually shown at the State fair suffered 
such marked injury that they were not fit for exhibit. 
In many cases the joints of both horses and cattle became so swollen 
and stiff, from standing in water where they sought protection from 
flies, that they could scarcely walk. The incessant stamping of the 
animals also had the effect of injuring the feet and joints. A number 
of liverymen found it necessary to discontinue making drives into 
the country, and some of their animals were completely disabled for 
regular work. 
Another source of loss to farmers was their inability to proceed 
with their usual farm plowing and other operations at the proper time. 
In many sections the flies were so bad on the horses that they could 
not stand both the work and flies. Some men resorted to night work 
as a means of escaping the attack, but this was too severe for the 
teams, as the flies allowed them no rest during the day. Numerous 
instances of horses becoming frantic from irritation were recorded; 
these often resulted in runaways and consequent destruction. Ani- 
mals which were not being worked sometimes received injuries from 
running into barbed wire fences in endeavoring to escape the flies. 
The total loss due to the outbreak in 1912 is difficult to estimate. 
It is believed that in northern Texas over 300 head of cattle, mules, 
and horses were killed directly or indirectly as the result of the fly 
attack. This actual death loss may be conservatively placed at 
$15,000. The loss due to the reduction in milk supply may reason- 
ably be placed at $10,000, and other losses far surpass these two 
items. Moreover, these were the losses experienced only in the few 
540 
