34
From this it would seem—
(1) The effects of the cause began to operate in July in A troop.
(2) They affected A and B in August, but A most.
(3) In September the disease raged in A, B, and C; even D also.
(4) In October it continued to an increased degree in A, was only h
as frequent in B, and still operative in C.
(5) In November it still acted on A and B, most so on the latter.
9 to A troop.
21 to B do.
19 to C do.
All these troops were subjected to the same climatic conditions, and all up to October
were watering at the Royal Lakes. We have seen why probably A troop suffered
most, but have no evidence that those causes acted specially in October on A troop
or specially on all the troops in September. D troop was broken up on 17th September
and the mules distributed in the other three stables ; four days
after this the mule of D troop which was affected in September
was admitted to treatment from B troop stable where he may
have (but also probably did not) obtained the disease. The mule puckals were
Substituted for the camel puckals in October in so far as I can ascertain, and since then
the small mules have done their share of puckal work.
32. After this detailed examination into the causes of the outbreak, we conclude
as follows:—
(a) A large size, horse-like " make," and gray color seems to predispose to
the disorder. Overwork, too, seems to increase liability, especially if
it be associated with insufficient food of bad quality.
(b) Collection of mules in numbers at one place, especially when in association
with a moderate uniform temperature and want of free circulation of
air; also exposure to weather during monsoon time when rain is falling
and the air sultry, " muggy," and stagnant; also use of food contami-
nated with marsh, slime, or water from marshy sources; possibly also
leech and mosquito bites act as determining causes.
(c) The spirilloid is the sole immediate cause.
33. TREATMENT.—The disease caused by spirilla in man is amenable to treatment
of a curative character, but hitherto the mule disease has resisted all efforts in that
direction. This is a great and important difference between the human and equine
disease, possibly attributable to natural expulsion of the parasites from the system of
man, but not of the mule. I have hitherto utterly failed in my attempts to learn
how the parasites escape from the systems of mules, and have arrived at the conclusion
that we have no evidence of their doing so under ordinary circumstances. If this be
actually the case, it entirely prevents our having success from adoption of the
eliminant plan of treatment. Our hands are further tied by the fact that probably no
improvement or reduction of the general health of a mule will render its system
unfit for the support of the spirilloids ; therefore the tonic system of fortifying the
constitution against the inroads and multiplication of the parasite does not offer
much chance of success. But one more curative means remains—the addition to the
blood of some agent which will destroy the parasites or check their development.
Results obtained by this method have not as yet been very promising. Our main
efforts must therefore be directed to prevention, to the ascertaining by close and
accurate observation of such determining causes as are most frequently present in
outbreaks and their removal, or else the prevention of possible victims being exposed
to them. A variety of medicinal agents have been resorted to in the attempt to find
a cure. Previous to my arrival Veterinary Surgeon (First-class) Frost tried salicylic
acid, hyposulphite of soda, and carbolic acid, but without success, and he had fallen
back on free administration of mucilaginous drinks as nutritives and to sheath the
ulcerated portions of the stomach. This treatment and large carbolic doses were being
resorted to on my arrival. I have tried ferruginous tonics, but have not found any
appreciable benefit from them, although continued for a long time ; the same negative
result followed the use of chiretta infusion and simple stimulants. I have only
had glimpses of benefit in dealing with two agents—oleum terebinthince and acidum
arseniosum. The former agent acts, not only as a stimulant and eliminative, but also
as an aromatic, compensating to an extent for deficiency of aromatic principles in the
fodder. In one case to which it was administered for some time the animal seemed to