344 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ III, IV.

goat virus is definitely of lower virulence than ox virus, it is probable that the
administration of smaller doses of serum would have achieved a more durable
immunity without lowering the safety factor to any marked degree. Although this
has not been done in calves, the view stated above receives ample support from the
results obtained by Cooper and Kerr [1931] in adult cattle.

With regard to the transmission or resuscitation of piroplasmosis, it may be noted
that no ox blood virus is used at this Institute if parasites can be detected by
microscopical examination of blood films, so that massive infection with these
parasites does not occur. In the present series the rate of complications due to
resuscitated piroplasmata (13 per cent.) is approximately the same as that
(11 per cent.) encountered by D'Costa and Balwant Singh in their considerably
larger series of inoculations in calves using ox virus. It would, therefore, appear
that in indigenous cattle piroplasmosis as a complication to anti-rinderpest inocula-
tions is largely, if not entirely, due to resuscitation. In further support of this
statement it may be observed that out of 266 bulls used at this Institute during
the years 1930 and 1931 for the testing or passage of goat virus 43 (16.5 per cent.)
developed piroplasmosis, while 105 (17 per cent.) out of 986 routine ox virus
producers developed this complication during the same period. At the same time
it may be stated that while there is no apparent advantage in indigenous cattle,
or in thoroughly acclimatised foreign breeds, as far as resuscitation or inoculation
of piroplasmosis is concerned, it is advisable to use goat virus in the case of newly
imported animals and those which have had no opportunity to become " premu-
nised " to the Indian strains of P. bigemina.

The results reported above indicate therefore that the use of an attenuated
virus derived from goats together with normal doses of serum on calves of indigen-
ous and acclimatised breeds has no advantages as compared with the usual serum
cum ox virus method and is definitely inferior to that method in the extent of
immunity produced. It is probable, however, that better results could be achieved
by the administration of smaller doses of serum, or indeed of goat virus alone.

                                                  SUMMARY.

1.  The results of the serum-simultaneous inoculation of 22 calves with goat
virus and serum are reported, together with the results of immunity tests carried
out at various intervals after the original immunisation.

2.  The use of an attenuated virus together with the usual doses of serum
leads to the production of a lower grade of immunity than when ox virus is used.

3.  The percentage of calves which develop an appreciable immunity is less
when goat virus is used than when ox virus is administered.