272
ABSTRACTS
[ Vol. XXIV, Part IV,
reservoir animals kept in complete isolation from other cattle. Their bedding and
hay were sterilized, and the only food which was not sterilized was the silage and the
concentrate ration. Since the Onderstepoort silage was shown to contain 4 per
cent acid, it was believed that any tubercle bacilli originally present in it would
be destroyed. The concentrate ration could carry viable tubercle bacilli, the source
of such infection was much more likely to be human than bovine. During the
last 30 years not a single case of tuberculosis was found in this group of isolation
stables. These animals were destroyed and in every case a post-mortem examina-
tion was made. Lesions were present in six out of the seven animals. The seventh
had actinomycosis, which was thought to have been responsible for the sensitiza-
tion in this animal. In four, the bovine type was identified. In one, the organism
was lost and in the sixth case the results were not yet available.
It was concluded that a human being with open pulmonary tuberculosis due
to the bovine type of organism must have been responsible for the infection. All
the available humans were tuberculin tested, medically examined and screened. A
number of them proved positive to tuberculin test but no clinical cases were found
on medical examination and on screening. Since the personnel was constantly
changing, it was not possible to examine all those who were in close contact with
these animals during the last two years.
In another group of three positive reactors no lesions were found and it was
considered that these animals were sensitized due to infection with human type of
organisms. The attendant in close contact with these animals was shown to have
pulmonary tuberculosis on screening, but upto the time of report the organisms
could not be identified in his sputum by direct smear examination, nor by biological
test.
The experience with the Onderstepoort herd suggested that man may become
the source of infection to the bovines with human type of organisms and thereby
sensitize the animals, and that pulmonary lesions due to the bovine type of organism
may become a dangerous source of infection for bovines.
The author concludes that man as a source of infection for bovines can no longer
be regarded a rare academic curiosity, but must be faced as an important practical
issue, where a serious attempt is being made to eradicate tuberculosis from cattle
and to maintain them free from sensitization. Where the bovine as a source of
infection has been eliminated and tuberculin tests are not carried out annually,
serious disastrous set-backs may occur, when a human being with open lesions due
to the bovine type of organism, introduces the infection in a herd. (B.R.S.G.)
The use of lapinised virus vaccine to suppress active rinderpest in susceptible grade
cattle. BROTHERSTON, J. G. (1951). Vet. Rec., 63, 235-238
I N this article the results of a field trial, with lyophilised, lapinised strain of
rinderpest vaccine in the face of severe infection, have been reported.
This vaccine was tried in preference to formalised spleen vaccine and Kabete
attenuated goat virus vaccine, because the lapinised virus vaccine, though still in