54                   Treatment of Equine Surra in Assam

and intrathecal doses were given. In very weak animals the initial intra-
venous dose was given half in the first week and the other half in the following
week.

The successful adoption of this method by the Army Department and
also by the various workers in the provinces resulted in the relaxation of
certain regulations contained in the Glanders and Farcy Act of 1899 under
which equine surra was scheduled. As a matter of fact, it may be noted that
the destruction of equines under the Act for surra turned out to be past
history consequent on the reliability and success of the treatment observed
in most of the cases.

This method of treatment involved fortnightly injections, intravenous
and intrathecal, extending to a period of one month, efficient assistance in
carrying out the intrathecal injections and also a good practice of the tech-
nique itself Field workers who had to undertake the treatment of a large
number of cases naturally found the method difficult, if not impossible. To
overcome the obvious difficulties encountered in field conditions, suggestions
were made and small experiments were carried out to ascertain the possi-
bility of reducing the period as well as the number of injections without
seriously interfering with the effect of the treatment.

Besides, some cases were observed where intravenous injection of Naganol
alone was capable of producing apparent recovery for a considerable period
[Edwards, 1928]. But the elaboration of an intrathecal technique solved
the difficult problem of sterilizing the cerebro-spinal system which otherwise
would be a safe abode for the parasites least affected by the drug. In such
cases relapses and even fatal terminations have been noted. It must also
be admitted that cases of this nature have been fortunately rare.

Various modifications were attempted to suit field conditions with a
view to:—

(1) reducing the number of injections,

(2) shortening the period of treatment,

(3) combining with cheaper drugs so as to lessen the cost of treat-
         ment.

Sen [1933] has described an interesting experiment on six horses under-
taken to determine the efficacy of single dose—treatment intravenously
with a dosage of 5 and 8 gm. per 1000 lb. body-weight. All of them recovered
satisfactorily in spite of the fact that some of the animals had developed well-
marked clinical symptoms.

Mahajan [1939] reports of having adopted a routine method of treat-
ment for equine surra by the single intravenous injection of Naganol in a
10 per cent solution, the dose being regulated at the rate of 50 c.c. per 1000
lb. body-weight. Out of the 28 cases treated 21 completely recovered,
while the remaining seven succumbed after a couple of months apparently
due to the residual parasites in the cerebro-spinal system.

The treatment suggested for equine surra (excepting advanced cases
with symptoms of nervous involvement) at the Imperial Veterinary Research
Institute, Mukteswar, consists of two injections, at an interval of 30 days ;
50 c.c. of a 10 per cent solution of Naganol per 1000 lb. body-weight being
used on each occasion. Although a single injection effects a cure the re-
inforcement by a second injection is advised.