OBSERVATIONS ON DOYLE'S DISEASE OF FOWLS

                                                    BY

                                       R. N. NAIK, G.B.V.C.,

                  Veterinary Investigation Officer, Bombay Presidency

                    [Received for publication on 27th August, 1936]

Doyle's disease, which is commonly known in India as Ranikhet disease,
is a disease of the greatest economic importance as it ranks first amongst the
diseases of fowls in causing mortality. It was first recognised in the United
Kingdom by Doyle in 1926 and in India by Dr. Edwards in 1927. Since then
it has been found prevalent in certain other parts of the world ; Piecard found
it in Java in 1928, Rodier in the Philippine in 1929 and Ochi and Hashimoto in
Korea in the same year. In the Bombay Presidency the disease was first recog-
nised by me in the year 1932 and materials from the artificially infected fowls
were forwarded to the Imperial Institute of Veterinary Research, Muktesar, for
confirmation. It is also understood that the disease is very extensively pre-
valent in various parts of India. It is a fatal disease and whenever it breaks out
in a village it wipes out the major portion of the fowl population if not the whole
and as a result poultry-breeding industry is sustaining very heavy losses every
year.

Unfortunately no curative treatment or prophylaxis against the disease
has been found out as yet. All efforts made by different workers in this respect
have, so far, proved abortive ; Doyle [1927] tried heat-killed virus without suc-
cess ; he, however, experimented with an anti-serum prepared from ducks
and found that birds treated with it failed to contract the disease by contact
but died when artificially infected. Cooper [1931], on the other hand, succeeded
in protecting birds against artificial infection by injecting serum prepared from
immune fowls. But as the quantity of serum obtained from a fowl or a duck is
extremely small this contribution to the knowledge of immunology has served
no practical purposes in dealing with the disease. Doyle [1927] further found,
in Great Britain, that formalinised virus when applied by the subcutaneous route
afforded considerable protection against natural infection but not against arti-
ficial one, whereas all attempts made in India at the Imperial Institute of Veteri-
nary Research, Muktesar, to prepare such a product either by treating the vital
organs with chloroform or formalin or by desiccating them in vacuo have proved
of no avail.

In the lay press in India one frequently comes across reports, evidently
written by fowl-breeders having little knowledge of the disease, and medicines
claiming good results obtained by the oral administration of kerosine oil or some
other stuff. But it is needless to say here that they have proved utterly useless
in saving the life of affected fowls.

                                                  (322)