ABSTRACTS
113
housed 600-700 yards away were not affected by the disease and so served as con-
trols. Serum-neutralization test of the affected birds proved positive and the
test was negative in the control birds.
The quality factors compared were weight, candling appearance, albumen score,
shell quality and deterioration of percentage of thick white. A total of 3,817 eggs
were examined. Eggs were also held at 100°F for 14 days to note the deterioration
in the percentage of thick white, and the rate of deterioration was observed by
keeping eggs at 100°F for 10 and 7 days and at 77°F for 7 days. Nine hundred and
twenty five eggs were opened out to observe the amount of blood spots in the
infected and in the control groups. Daily egg production and mortality were
maintained in both the groups.
After recovery, the difference in egg weight of pullets affected with New Castle
disease was significant at 1 per cent level as compared to controls, throughout the
months of June, July, September and October. The control birds laid better quality
eggs as compared to New Castle disease-recovered pullets, as judged by candling.
When the eggs were kept at 100°F for 14 days the loss in percentage of thick white
was practically the same in both groups, before the onset of the disease. The thick
albumen of the control group declined by about 27 per cent more in the summer
than in the winter, whereas the thick albumen in the eggs of the experimental pullets
declined by about 142.0 per cent. The summer eggs of control pullets registered a
slightly higher percentage of thick white than the winter eggs but in the experi-
mental birds the total weight of albumen decreased slightly but the total weight
of percentage of thick white increased slightly or remained constant, resulting in
a slightly higher percentage of the thick white.
With respect to candling quality, albumen score and egg weight less, New Castle
disease-recovered pullets laid inferior eggs as compared to the controls. Even
though the percentage of thick white of the infected pullets was slightly higher
than in the non-infected pullets, the albumen score of the former was lower than
the latter indicating that the apparent viscosity of the thick white had been
severely damaged.
The weight of eggs of the New Castle disease-recovered pullets was less as com-
pared to controls but when incubated the loss in weight of the experimental bird
was lower in comparison to the controls, thus indicating better shells for the experi-
mental birds. But this was an exception as infection of New Castle disease in
cutbred, cross-bred and incross-bred pullets registered watery albumen, poor shape
and texture of shell after recovery.
Out of 459 eggs of the infected pullets examined, 15 registered blood sports as
compared to 14 blood sports in 466 eggs of the normal pullets, thus indicating that
the New Castle disease does not affect the incidence of blood sports.
There was a sharp drop in egg production with the onset of the disease but
returned to normal after registering " zero " production, which is characteristic of
the disease. Mortality was higher in the group that recovered after the disease
than in the controls due perhaps to the lowered vitality resulting from the outbreak
of the New Castle disease. (T. D. M.)