JOHN
FFRANCIS
235
Avian tuberculin 0.1 c.c. was injected into the web
of the feet in the geese and ducks but none reacted
positively to this test. This method of testing in
ducks and geese according to Craig and Davies
[1937] is of no practical value in the diagnosis of
tuberculosis. Dobson and others [1941] conclude
that the tuberculin test carried out intradermally
in the skin of the neck and in the cloaca and in
conjunctiva with synthetic avian tuberculin was
of no value in the diagnosis of tuberculosis in ducks.
ACKNOWLEDGEMENT
The writer is grateful to Mr L. Sahai, M.Sc.,
M.R.C.V.S., of Imperial Veterinary Research
Institute, Mukteswar, for confirmation of the dia-
gnosis and also for supplying the references to the
literature on the incidence of avian tuberculosis in
ducks and geese in India and elsewhere. The author
also takes this opportunity to express his thanks to
Mr Md. Aziz Hassan, for his keen interest in this
work and also to Mr K. Raghavachari, for his
suggestions in preparing this article.
REFERENCES
Craig, J. F. and Davies, G.O. (1937). Vet. Rec. 49, 29.
Dobson, N. and others. (1941). Vet. Rec. 53, 575-580.
Dobson, N. and Spears, H. (1941). Vel. Rec. 53, 365-370.
Eber, A. (1924). Die Tuberkulose des Hausgeflugel.
Feldman, W. H. (1938). Avian tuberculosis infections.
Haustiere. Z. Infektr. 25, 145-175(1925). Z. Infectkr.
Haustiere. 27, 1-19.
Baillier Tindall and Cox, London.
Iyer, G. S. (1943). Indian Poull Gaz 26, 8-10.
Klimmer, M. (1930). Berl. tierarztl, Wschr 46, 702-710
Lænkholni, W. Quoted by Zeller.
Picard, W. K. (1927). Ned.-ind. Bl. Diergeneesk. 39,
391-396.
Zeller, H. (1932). Die Tuberkulose des Geflugels. Ergebn.
d. all. Path. u. path. Anat. 26, 804-876.
SELECTED ARTICLE
A REVIEW OF THE RESPIRATORY DISEASES OF THE HORSE
By JOHN FRANCIS, B. Sc., M.R.C.V.S.
(Reprinted from The Journal of the Royal Army Veterinary Corps, Vol. 14, No. 1, November 1942)
READING the older veterinary authors e.g. Smith,
[1897]; Law, [1902], Friedberger and Fröhner, [1908],
one is struck by the scope and accuracy of their
clinical and pathological observations. A vast
amount of research, particularly in Germany and
France, has been carried out on the respiratory
diseases of the horse, but most of it was done before
the days of motor transport; that is, before the
methods of research into the ætiology of bacterial
and virus diseases had been perfected, and as this
group of diseases is particularly difficult to study
it is not surprising that the subject is still some-
what confused. However, after having paid some
attention to the question of predisposing causes and
secondary bacterial invasion, an attempt will be
made to assess the evidence that there are four
respiratory diseases of the horse each primarily due
to a specific virus infection.
It is far from easy to show experimentally that,
adverse environmental conditions will cause the
onset of pneumonia, but all clinical observers appear
to agree that they are of great importance in preci-
pitating attacks of equine respiratory diseases.
In a very fine clinical article on ' Pneumonia and
Pleurisy in the Horse,' the late Sir Frederick Smith
[1897] quotes Hunting as saying that ' want of
condition, plus fast work, causes exhaustion, and
then we only want cold, changeable weather to
produce diseases of the lungs.' Smith believed ex-
haustion to be a ' direct exciting ' cause of pneumonia,
especially in young, soft horses, whereas older
horses seem to possess a comparative immunity
against some of the ' causes or conditions ' which
so freely contribute to the production of the disease
in the young. Smith realized that the febrile
attacks from which nearly all young horses suffer
when first brought into stables may be associated
with the process of acquiring immunity to the
' pneumonia microbe.' Pneumonia chiefly affects
stabled horses and the great importance of good
hygienic conditions is shown by the fact that five
years after the introduction of ' sanitary science '
into the French Army the annual incidence of pneu-
monia had dropped from 110 to 46 per thousand
horses, and four years later to little more than 3½
per thousand. Long rail and sea journeys also
predispose to pneumonia. Coleman (Principal of
the Royal Veterinary College, 1794-1839) laid great
emphasis on the importance of well-ventilated
stables, but unfortunately he did not display equally
good judgement on many other subjects.
In parentheses, it may be said that the clinical
methods of examining the chest and the ' respiratory
sounds,' described by Smith will be of great interest