112 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, II

rapidly fatal cases the carcase upon post-mortem examination often appears
indistinguishable from that of a healthy fowl. The most striking fact is the
complete absence of any recognisable lesion in the lungs of birds which have
exhibited perhaps extreme respiratory distress during life.

                                    CONTROL MEASURES.

         Research work undertaken at this Institute under the above head has been
confined almost entirely to the laboratory, and the application of control measures
in natural outbreaks of the disease has not yet been attempted on any large scale by
us.

         In view of the tenacious nature of the viability of the virus, it is remarkable
that the disease was controlled with both speed and effectiveness in the two
outbreaks which occurred last year upon the farm of the United Provinces Poultry
Association at Lucknow, referred to earlier in this paper. The flock on this farm
comprised as many as 1,300 valuable pedigree birds, and were it not for the prompt
and energetic measures adopted by Mrs. Fawkes-Ansell, the Secretary of the Associa-
tion, in combating the outbreaks, the percentage of mortality amongst the birds
exposed to infection would doubtless have run to a high figure. Yet the measures
consisted only in destruction of the fowls exhibiting symptoms, addition of
permanganate of potash or iodine to the drinking water and food of all non-affected
birds, and the liberal use of phenyle compounds in the houses and pens. Upon both
occasions the disease was stamped out immediately, with the loss only of the affected
birds sacrificed. Experiments have recently been carried out in this Institute
upon the possibility of controlling the disease by the application of (1) serum
derived from fowls that had recently recovered from the artificially induced disease ;

(2)  serum prepared from donkeys injected with "Ranikhet disease virus" and

(3) vaccine prepared from organs of diseased fowls.

         (1) The results of a preliminary test with the fowl serum are shown in the
following table:—