12 REPORT OF THE IMPERIAL INSTITUTE OF VETERINARY RESEARCH,
financial year ending March, 1925. Since that year, the revised methods
of production, standardization and issue have been developed upon the
same lines, so that for some time they have become standard processes.
Anti-rinderpest serum is now made wholly, or wholly save for some
small quantities resulting from experimental work, at the Izatnagar
Branch Institute, whence it is despatched, in consignments designated
according to the produce of the various stages of manufacture, to
Muktesar, for storage, careful testing of the variously designated consign-
ments, mixing for issue according to the potency indicated by the tests,
bottling, packing, and issue. The serum is made entirely by the
" immune " method, which requires careful expert supervision to obtain
the largest yield of dependable serum. Manufacture is undertaken
throughout the year, but experience has shown that it is made most satis-
factorily during the cooler months of the year; hence the rate of manu-
facture is greatly increased in the cold weather. The aim has been to issue
regularly a serum of uniform potency for the preventive inoculation,
by the " serum-alone " method, and very large brews are now mixed
together, the constituents of which have been subjected to rigorous tests.
In former years, when the reserves maintained were low, the custom was
to prepare relatively minute brews, some of which were undoubtedly
of very high potency, but a large number of which were probably of low
and certainly of irregular potency. The present policy seems to have
succeeded very well, judging from the fact that complaints regarding
the reported inefficacy of the serum are not received.
For the serum-simultaneous inoculation, an endeavour is made to
prepare separately a serum of very high potency, representing the yield
of the buffalo producers during the earlier stages of extraction. Serum
destined for this treatment is submitted to somewhat exhaustive tests
for its potency and safety when employed in large doses.
When the Mysore authorities undertook to carry out this treatment
on a large scale in 1925, the resources of the Institute were hard pressed
to deliver guaranteed supplies in the large quantities required, con-
currently with the heavy demands that were coming in for serum for
the preventive inoculation, for which a large proportion of serum of the
highest potency is also necessary for admixture. However, the requisite
serum was successfully issued, and the results reported by the Mysore
staff are most encouraging. In a communication received in February,
1927, 49,244 cattle were reported to have been immunized, with a morta¬
lity of 344 (=0.69 per cent.). This mortality would appear to be the
lowest of which there is authentic record. The Egyptian veterinary
authorities have had experience of the method as their standard method
of protection over several years, and among 5,14,452 cattle immunized
by them during the years 1912 to 1921 the mortality was 4,688 (=0.91
per cent.). It would therefore seem that for indigenous Indian cattle
the serum-simultaneous method of protection against rinderpest is
strongly indicated both from the known durability of its effects and its
relative safety. It is likely that a necessary means of ensuring it s