BULLETIN OF THE 
No. 147 
Contribution from the Bureau of Animal Industry, A. D. Melvin, Chief 
January 16, 1915. 
THE EFFECT OF THE CATTLE TICK UPON THE 
MILK PRODUCTION OF DAIRY COWS. 
By T. E. Woodward and W. F. Turner, Dairy Division, and Cooper Curtice, 
Zoological Division. 
INTRODUCTION. 
The common cattle tick, Mar gar opus annulatus, infests the cattle 
throughout the greater part of Florida, Georgia, Alabama, Louisiana, 
and Arkansas, large portions of Texas, Oklahoma, Mississippi, 
South and North Carolina, and small areas in Virginia and Cali- 
fornia. On account of the enormous losses occasioned by the para- 
site, it has been necessary to quarantine the area infested, so that 
cattle outside of this area may be protected. Ever since 1906 tick 
eradication in the infested area has been actively pushed by Federal 
and State governments, cooperating with citizens of tick-infested 
regions, to destroy the pest. While the majority of farmers admit 
some loss, few are aware of its extent, hence the experiments reported 
in this bulletin were undertaken to bring out the facts, particularly 
in relation to the effect of the tick on dairy cows.. 
The cattle tick is an almost exclusive parasite of cattle. While 
the ticks may mature on horses, mules, and possibly deer and sheep, 
their control on these animals has proved to be comparatively e&sy. 
All ticks come from eggs laid by the adult female ticks. An engorged 
female tick dropping from a cow completes oviposition in from five 
days to a week; the eggs hatch as a rule in about 21 days in ordinary 
summer weather; the issuing seed ticks crawl upon the grass and 
await the coming of cattle upon which they crawl when opportunity 
offers; they then reach maturity in from 21 to 25 days. 
While maturing each tick abstracts a definite amount of blood 
from an animal, and to that degree injures it. The quantity of 
blood abstracted is many times the weight of the ticks when grown, 
for these represent only that part of the solids and fluids of the 
blood which may be converted into the tissues of the tick, the remain- 
ing solids and fluids being rejected. The amount of blood taken 
58970°— Bull. 147—15 1 
