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ABSTRACTS
Rumen samples obtained at the end of each digestion period were examined
for counts of the rumen bacterial populations, gram stain morphology observations
and cultural work pertaining to the physiology of the rumen bacteria present.
These studies with and without the casein additions revealed differences which
correlated closely with the degree of roughage digestion. The results offer further
evidence of the need for a minimum protein requirement for efficient roughage
digestion in cattle, especially when starch or starchy grains make up a part of the
ration. This minimum protein requirement is interpreted as presenting a protein
(nitrogen) requirement for the growth of rumen micro-organisms directly involved
in roughage digestion. (B.D.)
Salmonella Organisms on and in Chicken Eggs. CANTOR, A. and MCFARLANE
VERNON. H. (1948). Poult. Sci. 27, 350-355
C ULTURES from shell scrapings after mixing with normal saline were made
on bismuth sulfite (Difco) agar plates and in tetrathionate brilliant green broth
while the egg meats after proper sterilization of the shell were directly dropped
into jars containing 50 c.c. of double strength Selenite-F enrichment broth or in
tetrathionate broth with or without brilliant green and later on streaked on bismuth
sulfite or MacConkey plates. In all, cultures were made from over two thousand
eggs and the findings revealed that 0.6 per cent of the samples of shell scrapings and
1.2 per cent of the samples of the egg meats were positive for Salmonella organisms,
while in no case the bacteria was isolated from the shell as well as the egg meat of
the same egg. The strains have been typed as S. pullorum from the egg meats
and S. montevideo and S. anatum from the shell scrapings.
The Salmonella organisms were more common in lower grades of eggs than
in any of the four higher quality grades. This is attributed to the presence of the
organisms in the intestinal contents and droppings and in turn to soiled eggs.
Apparently cleaning of low grade dirty eggs in the farm may increase the chances of
the infection inside the contents before reaching the consumer, necessitating pasteu-
rization prior to processing, in order to prevent contamination of the egg powder.
The concurrent presence of Coliform and Salmonella organisms in samples of
shell scrapings has also been studied. (B.M.T.)
Reproductive Failure—in the Bull—Its Diagnosis and Prognosis. ROLLINSON, D.H.L.
(1950). Vet. Rec. 36, (62) 527
T HE author suggests some practical points for evaluating the breeding history
of the bull. Figures of bulls slaughtered in Great Britain, since 1941, have
been presented. The infertility and sterility rate in the bulls appears to lie
in the region of 10-20 per cent. Incidence of reproductive disorder in 82 abnormal-
cases from various breeds has been recorded. 53.03 per cent cases had testicular
degeneration and 18.51 per cent suffered from congenital defects.
The method of assessing the reproductive health of the bull has been described
in detail. According to the author, in all cases of developmental abnormality
aplaia or hypoplasl a reproductide of tract, trichomnoiasis, brucellosis, and C.
pyogenes infection of the epididymis the prognosis is grave. Cases of early or