DEMODECTIC MANGE OF GOATS IN INDIA
By M. K. SREENIVASAN, G.M.V.C., and S. W. H. RIZVI, G.B.V.C., Imperial Veterinary Research
Institute, Mukteswar
(Received for publication on 8 September 1945)
(With Plate XVIII)
DEMODECTIC mange of goats has been known in
Europe since 1881 when Niederhausern [1881] re-
corded the first case at Berne. Nocard and Railliet
[1885] recorded the second case at Alfort, and Railliet
[1895] described the mite and named it Demodex
folliculorum var. caprae. Thereafter different work-
ers reported the occurrence of this infection in other
parts of Europe. In U.S.A. the first case was re-
corded by Cram [1925], and recently Durant [1944]
has recorded some more. To our knowledge demo-
dectic mange of goats has not so far been reported
in India.
HISTORY
A batch of 50 female goats was purchased in March
1944 from a goat market in Bareilly district of the
United Provinces. All these goats were picked out
from different herds of far off localities arriving at the
market on the same day. They were brought to
Mukteswar and housed in an out-kraal, where there
was no previous history of such infection. The
number of goats purchased from any one herd did
not exceed five. All the animals are of non-descript
plains breed with short-haired coats, and are being
maintained by the Institute for breeding. In July
1944, some of the kids of this herd were found having
mangy eruptions on and under the ears, but scrapings
of the affected parts were negative for mites. The non-
specific nature of the lesions in kids prompted us to
examine all the goats thoroughly with the result
that two goats were found with a squamous type of
itch on the surface and border of the ears, while one
goat showed nodules on the face and neck. The
material from both types of lesions was found to
contain Demodex. One of us (S.W.H.R.) has an
opportunity to examine about 500 goats at the
same market recently and was able to detect a few
suffering from demodectic mange. This diagnosis
was confirmed microscopically. The infection
appears to exist in Farukhabad and Etah districts of
United Provinces from where these goats had come.
CLINICAL FEATURES
Three types of lesion were encountered, viz. (1)
discrete, nodules, (2) squamous dermatitis and
(3) acute dermatitis over coalesced nodules with
slight matting of the hair.
The goat showing the nodular form was rather
weak and had two kids to suckle. The nodules
varied in size from a millet seed to that of a pea and
were quite common and discrete on the face, neck and
shoulders (Plate XVIII, fig. 1); a few were noticed
on other parts of the body. On pressing the nodules
a thick, greyish, ribbon-like material oozed out.
This material was a mass of mites at all develop-
mental stages with nymphal casts. The contents
of a pea-sized nodule might roughly contain 22,000
mites. Very little loss of hair was noticed in this
form but there was occasional itching.
In the squamous type, loss of hair was well marked.
The lesions varied in size from a silver two-anna bit
to an eight-anna piece and even bigger in some cases.
The lesions were more or less circular and covered
with dry reddish-grey discharge which made them
appear raised. Scraping the lesion was quite pain-
ful and revealed a vascular base. The mites were
not numerous in lesions of this type and no nodules
could be detected in the affected area. The lesions
were confined mostly to the ears and in some cases
to the back and face (Plate XVIII, fig. 2). Harden-
bergh and Schlotthauer [1925] reported a case of the
squamous type of Demodex infection in goats in
U.S.A. In the acute form, nodules of small size
coalesced together and burst releasing a discharge
which caused matting of the hair. There was more
itching in this form and the goats lost condition.
Probably the hair follicles were not affected as
there was no loss of hair. Sometimes the lesion also
extended to the teats (Plate XVIII, fig. 3).
The course of the disease in its nodular form appears
to be indefinite, but in the squamous and acute
diffuse forms it is shorter and can perhaps be con-
trolled. It is necessary to mention that, as soon as
the disease was detected, all goats with the slightest
suspicion of infection were removed from the healthy
stock but on subsequent examinations of the' healthy'
lot it was possible to pick out a few more infected
animals. In all six out of 45 goats were declared
diseased. The youngest animal found naturally
affected was one and half year of age. No kid, even
though in contact with an infected mother, has so
far been found to be affected and this is in conformity
with the observations of Hardenbergh and Schlott-
hauer [1925].
TRANSMISSION
Experimental transmission of demodectic mange is
said to be very difficult and no positive results appear
to have been reported. Mohler [1940] mentions
that attempts to transfer the Demodex of cattle by
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