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Salmon, the Chief of the Bureau of Animal Industry, Washington, leave no
doubt that the species are identical. It would therefore seem that we un-
doubtedly have the tick, but so far as our investigations go we certainly have
not got the tick fever plague in India. Fortunately for India, the power to
control the disease is within our own hands. All animals may be put through
a thorough inspection before embarkation, and a long sea voyage intervenes
before they arrive at this country, and if requisite measures are taken both at
the ports of embarkation and debarkation, there seems to be no reason why the
pest should not be rigidly excluded.
601. One thing is very certain, that is that we should most firmly prevent
horned cattle from being carried on any ships on which horses intended for
India are carried. It is a well recognised fact that the disease germ of Tick
Fever, Pyrosoma bigminam, remains in the blood of a "recovered" animal for
years, and is known to be infective. Dr. Tidswell of the Board of Health,
Sydney, has conducted some extremely interesting experiments, and to show
the danger of importing homed cattle into India the following précis may
be of interest.
602. On 21st July 1898, two cows, Nos. 2 and 3, received under the skin
a preventive inoculation of 10 c. c. of " recovered " blood. In both fever ap-
peared on July 29th and lasted five days. Nine weeks after the subsidence of
the fever, the cows were injected with virulent blood and neither animal showed
any reaction after the second injection. In cow No. 2, with which we propose
to deal specially, it is estimated that in the course of fourteen days the blood
corpuscles were reduced from 6½ to 4½ millions per cubic millimetre.
603. It will be seen that cow No. 2 was a mild case, and had become
"salted", that is, protected from a further attack of the disease. Her fever
lasted but five days, and the temperature was above 103° for only 36 hours.
Blood from this cow was injected into cow No. 7. Fever developed in eight
days, and lasted nine during seven of which the fever was over 103° F. and
the symptoms more marked. From cow No. 7 blood was injected into cow
No. 9. Fever developed in six days and lasted nine during seven of which
fever was over 103° F. and the red corpuscles were reduced from 5½ to 3½
millions per millimetre. The animal rapidly wasted away and had to be
destroyed. It will be seen that infected blood carried through two removes
from No. 2, a mild case, clearly showed that at each remove the disease became
proportionately more virulent.
604. The lesson that these experiments teaches us is this, that if cows are
imported with horses, and they have recovered from the disease, the micro-
organism is still to be found in their systems. We know that the country
round our big ports abounds with ticks, and if these get on the imported cows,
they will, by sucking the blood, become the hosts of the Pyrosoma, and thus
start Tick Fever in this country, the disastrous results of which it would be
impossible to calculate.
605. Early information of the departure of horse ships from Australia is
obtained by this Department, and this is communicated to the various Super
intendents so that they may be on the watch, and have ample time to arrange
and carry out their inspections. It would, however, seem more efficacious if
all horses, previous to being shipped to this country, were passed through a dip
twice within fourteen days before being walked on board. This would get rid
of at least nearly all the ticks. Dr. Salmon of Washington issued a note in
which it was stated that the Bureau of Animal Industry had had a remarkable
success in perfecting a dip that takes the ticks from cattle, and made it practi-
cal to move their herds about freely. In order to test the dip thoroughly,
about 1,000 head of cattle were dipped at Fort Worth, Tex., and thence shipped
to Northern Illinois and placed with susceptible cattle. The ticks were all
killed, and the disease was not communicated to the susceptible cattle. This
information was very important, and the Bureau of Animal Industry was
communicated with in order to ascertain the nature of this new dip, as it was
thought that if this proved to be as successful as was claimed for it, the
Queensland Authorities might be asked to issue orders to the effect that all
horses intended for exportation to India should be effectively dipped within
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