THE DIAGNOSIS OF "REDWATER" (PIROPLASMOSIS) IN

                                      INDIAN CATTLE.*

                                               BY

                            HUGH COOPER, M.R.C.V.S., I.V.S.,

                                          Pathologist,

                                              AND

                            P. R. KRISHNA IYER, G.M.V.C.,

            Veterinary Inspector, Imperial Institute of Veterinary Research, Muktesar.

                  (Received for publication on 30th July 1931.)

In two articles contributed from this Institute to another Journal † a brief
account was given of the group of diseases known as the " Piroplasmoses " which
affect cattle in India. The object of the present article is to discuss the difficulties
that are not infrequently encountered in the diagnosis of the form of bovine piro-
plasmosis known as Tropical Redwater, caused by the protozoan parasite,
Babesia bigemina.

Tropical Redwater is a tick-borne disease and the transmitting tick in India is
believed to be Boophilus australis. The term " redwater " owes its origin to the
fact that the most striking symptom of the disease is the passing of red-coloured
urine (hæmoglobinuria) resulting from the destruction of red blood-corpuscles with
the consequent liberation of hæmoglobin. In countries, such as India, where the
disease is indigenous and widespread, cattle become infected as calves, at which age
they possess a high degree of natural resistance and thus acquire immunity by
virtue of becoming " carriers " of the parasite in a latent state of activity for the
rest of their lives. Clinical cases of acute and severe piroplasmosis as a primary
affection in adults occur in cattle imported from countries where the disease is
unknown, whilst in indigenous cattle the condition indicates an escape from infec-
tion early in life. The presence of these parasites in " carrier " animals, although

* Paper read at the 17th Indian Science Congress, Allahabad, 1930.

† 1. " Tick-borne Disease with some Remarks on the Diseases of Cattle caused by Protozoa ", by
Hugh Cooper, Agri. Jour. India, Vol. XXI, pp. 95—100 ; March 1926.

2. " The Piroplasmoses of Cattle in India", by Hugh Cooper, Agri. Jour. India, Vol. XXI,
pp. 313—317 ; July 1926.

                                              ( 296 )