174
POSSIBILITY OF VIBRIO FOETUS INFECTION
[Vol. XXIV, Part III,
abortus standard antigen obtained from the Indian Veterinary Research Institute,
Mukteswar. The results obtained were as follows:
In herd 1, vaginal mucus of 23 cows and five buffaloes was tested. Only one
buffalo gave a positive reaction ; and this reaction was so strongly positive that
marked agglutination occurred even in 1: 320 dilution of the original mucus
suspension. Moreover, the suspension of vaginal mucus collected on the first occasion
remained in the refrigerator for some weeks, and it always gave strongly positive
agglutination reactions on tests done at periodical intervals. On one occasion, the
blood serum of this animal was also tested and it was found to contain agglutinins
to a titre of 1 : 160 for V. foetus and 1 : 40 (P) for Br. abortus. The remaining 27
animals were negative. This herd was badly infected with brucellosis and the rate of
fertility was very low, services being frequently repeated.
In herd 2, vaginal mucus of 29 cows and six sexually mature female calves was
tested, and of these six cows and three female calves were found weakly positive for
V. foetus infection. The agglutinations obtained in this herd were, however, neither
so marked nor so clear-cut as in the case of the buffalo in herd 1. Two attempts to
recover V. foetus on culture from vaginal mucus of female calves (at oestrus), and also
from one aborted buffalo foetus, proved fruitless. A moderate degree of Br. abortus
infection, accompanied by stray abortions, was present in this herd.
In herd 3, vaginal mucus was collected from 14 cows and 10 sexually mature
female calves (including two buffalo calves). Simultaneously, blood serum was
subjected to agglutination tests for brucellosis as well as V. foetus infection. Majo-
rity of the animals tested gave weakly positive reactions (vaginal mucus as well as
blood serum) indicating V. foetus infection, but in this case also the agglutinations
were not so clear-cut or marked as in the case of the buffalo of herd 1.
In view of the agglutination reactions with the Rotterdam antigen being gene-
rally ill-defined, the results could not be accepted as quite dependable, and it was
considered advisable to test the specimens against antigens prepared with some
other strains as well. The most reliable antigen would probably be one prepared
with a suitable Indian strain of V. foetus ; but, since no Indian strain was available,
specimens of vaginal mucus and blood serum from about 20 animals were forwarded
to Dr J. R. Lawson at the Veterinary Laboratory, Weybridge, England. The results
of the agglutination tests kindly conducted by Dr Lawson against two different
V. foetus antigens showed that only one specimen of vaginal mucus, i.e. from the
strongly positive buffalo of herd 1, showed marked agglutination and was consi-
dered positive. None of the specimens of blood serum caused agglutination in
dilutions above 1 : 40.
From the results of tests conducted in India and in England it appears that
there was at least one animal which could be regarded as infected with V. foetus.
SUMMARY
1. Vaginal mucus of 89 cows and buffaloes, including a few sexually mature
female calves, belonging to three different herds which experienced a varying degree
of breeding troubles, was tested for V. foetus agglutinins.
2. Positive agglutination reactions were encountered in 20 cows, nine sexually
mature calves and one buffalo ; but, except in the case of the buffalo, the agglutina-
tions were weak and rather ill-defined.