308          'Lahore Canine Fever' and 'Tick Fever' of dogs

Lastly, it is believed that much of the refusal to consider the possibility
of ' Lahore Canine Fever ' as being in reality a P. gibsoni infection, has origi-
nated in the widespread belief that Novarsenobillon and similar drugs have a
specific curative effect in P. gibsoni infections. While a very few cases of
' Lahore Canine Fever' have been successfully treated with Tryparsamide
and Novarsenobillon, the great majority of cases have failed to respond to
treatment. The writer conducted a series of experiments on the treatment of
experimentally produced P. gibsoni infection in dogs. The results will shortly
be published, but at this juncture it may be stated that no drug was found that
could be said to have any curative or specific effect in this infection.

In view of the experimental evidence, supported by these observations,
it is believed that' Lahore Canine Fever,' which finds its counterpart in' Canine
Enteric Fever ' and ' Canine Typhus Fever' is, in actuality, ' Tick Fever ',
associated with P. gibsoni infection.

                          SUMMARY AND CONCLUSIONS

1. ' Lahore Canine Fever ' is one of the most important causes of death of
dogs in Lahore and evidence is adduced to show that it is the same disease as
has been investigated by workers in other parts of India and designated various-
ly ' Canine Typhus Fever ' and ' Canine Enteric Fever '.

2. The disease occurs during the tick seasons, but has not been accepted
as ' tick fever ', through general inability to demonstrate the causal parasite in
the blood of infected dogs, combined with the general refractoriness to treat-
ment with arsenical preparations.

3. The latter aspect of the disease will be dealt with in a later article.

4. An account is given of the clinical features and pathology of ' Lahore
Canine Fever' with a comparison of experimentally produced disease of P.
gibsoni origin.

5. The proof that ' Lahore Canine Fever ' is ' tick fever ' is based on the
following observations:—

    (a) P. gibsoni is occasionally, with difficulty, demonstrated in the blood
      at some stage of the illness, frequently just before death.
    (b) The clinical syndrome of an authentic experimentally-produced
      P. gibsoni infection corresponds in every detail with that of
      ' Lahore Canine Fever '.
   (c) In both diseases the cytological changes occurring in the blood
      cells and the method of production of secondary anaemia are
      parallel.
    (d) The histo-pathological changes in the reticulo-endothelial system,
      especially in the spleen, reveal important findings which estab-
      lish the relationship of ' Lahore Canine Fever ' to ' tick fever '.