September, 1952] S. B. V. RAO, S. NARAYANAN, D. R. RAMANI AND J. DAS 203
Four out of the six chicks were seropositive after 12 days but heart blood and
liver cultures were sterile. The organism was recovered from the livers of the two
chicks which were seronegative.
BACTERIOLOGY
Isolation of the organism from the heart blood and liver. The organism
was isolated from acute cases from the heart blood and livers, of chicks
and adults dying after a brief period of illness. The colonies, on plain agar
appeared as fine granular pin-point in 24 hours and developed into smooth glistening
translucent hemispheres in 48 hours of incubation, and later they varied from round
to angular. The heart blood usually yielded a pure culture, while liver cultures
sometimes required sieving through brilliant green broth and plating on to Macconkey
media.
Isolation from the ovaries of the reactors. In cases of abnormal ovum, culture
was obtained by searing the ovisac puncturing and pipetting out the whole con-
tents into brilliant green broth, about 200 c.c. per ovum, and incubating for 48
hours and then plating on to Macconkey for recovery of the organism. Where
lesions were not well marked and the ovary was found arrested in its growth, the
bunch of the immature ova was tritutated and transferred to a large quantity of
tetrathionate broth from 200 to 500 c.c. depending, upon the size of the bunch and
incubated for 24 to 48 hours before recovery by plating on to Macconkey. By
these two methods 19 out of 24 ovaries of reactors yielded positive cultures.
Isolation of the organism from eggs of the Reactors. Thirty-six eggs from a pen
exculsively of carriers were cultured in five batches. The eggs were opened after
washing in 5 per cent dettol, dipping in alcohol, flaming lightly, and opening into
a sterile petri dish. The whole yolk was spooned out into 200 c.c. of broth, and
incubated for 48 hours, while the white was discarded. The organism was recovered
on Macconkey plate. 13 out of the 36 eggs thus cultured gave positive results
which proves that over 36 per cent of the eggs laid by carriers might be infected.
Isolation from the intestines of baby chicks and adults. Materials from the duode-
num of baby chicks with white diarrhoea, and from adults showing enteritis were
incubated in separate isolation experiments in terathionate broth to which brilliant
green in 1 to 50,000 proportion had been added. After 48 hours of incubation the
organism was recovered on Macconkey media in the usual way, but several sievings
were continued through the special media before pure culture was obtained.
Indentification of S. gallinarum. In all cases of isolation on Macconkey plates
fine white colonies were picked up and. sown on agar slants serially. Those colonies
which yielded non-motile gram negative slender rods were tested for their antigenic
specificity by the rapid serum method of Stafseth and Carbutt [1940] before sub-
mitting to principal sugar tests for confirmation.
Pathogenicity. Rabbits and guinea pigs were killed in 48 hours by the sub-
cutaneous route, evincing septicaemic lesions of an acute haemorrhagic type on
heart, stomach, and intestines (Plate XIII, fig. 4). It proved fatal to pigeons after
five days by the intramuscular route. The pigeon went down on both legs and was
supporting itself on its out-spread wings on the fourth day. The post-mortem
findings were, large areas of necrosis in the pectoral muscles at the site of inoculation