THE CONTROL OF BLOOD-SUCKING INSECTS IN INDIA.

                                                         BY

                                         S. K. SEN, M.Sc., F.E.S.,

Assistant Research Officer, Imperial Institute of Veterinary Research, Muktesar.

                          (Received for publication on 5th November 1931.)

The problem of the control of blood-sucking insects has now assumed a position
of paramount importance in Veterinary Entomology in view of the fact that several
species of these insects have, during recent years, been definitely incriminated as
the carriers of certain tropical diseases of animals. The most notable of such
diseases is surra, which has been repeatedly demonstrated by Nieschulz [1928,
1929], in Java, to be capable of being conveyed mechanically through the bite of
Tabanus rubidus, whilst Moutia [1928-29], in Mauritius, has brought forward what
would appear to be fairly convincing evidence in support of his contention that the
same disease is conveyed through the agency of Stomoxys in that country. In
India, the disease has been shewn by Cross and his collaborators [1922, 1924] to be
capable of being transmitted through the bites of several species of Tabanids,
including T. rubidus. The fact that in all cases the disease has proved to be trans-
missible mechanically makes every single biting insect a potential carrier not only
of surra, but, possibly, of several other blood-borne infections of animals.

The problem of the control of Tabanids will be discussed at length in another
article which it is proposed to submit shortly for publication in this Journal,* so
that in the present note, it is only necessary briefly to deal with this subject, but
to consider in some detail the more important measures advocated by different
workers for the control of biting flies other than the Tabanidæ. A brief mention
will also be made of some of the known methods for combating house-flies
(Muscidæ) and blow-flies (Calliphoridæ), inasmuch as these methods may prove to
be of value in devising measures for the control of blood-sucking insects.

The more important of the measures hitherto recommended for the control of
insect pests of animals may be classified under the following categories :—

                                                  I. REPELLENTS.

During recent years, a considerable number of repellents designed to repel
flies, primarily by virtue of their obnoxious smell and greasy properties, have been.

* In the series of articles entitled " A Veterinary Entomology for India," by T. Bainbrigge
Fletcher and S. K. Sen.

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