CONGENITAL "BLINDNESS" OF CALVES IN INDIA.

                      A RÉSUMÉ OF THE POSITION.

                                           BY

               CAPTAIN S. C. A. DATTA, B.Sc., M.R.C.V.S.,

Temporary Veterinary Research Officer, Imperial Institute of Veterinary Research,
                                      Muktesar.

                  (Received for publication on 17th August 1932.)

                              (With Plates XXI—XXIII and one chart.)

The object of the present résumé is to place on record in a brief compass the
information available at Muktesar on the occurrence of a peculiar " blindness " in
calves in India, in the hope that this will stimulate interest in the condition
amongst field workers, and lead possibly to the collection of further information
regarding its incidence. The seriousness and economic importance attaching to the
problem may be appreciated from the fact that an apprehension has been expressed
by some of the authorities concerned that cattle breeding at the Military Dairy
Farm at Quetta may have to be given up entirely if the condition of " blind
calves ", which is so common there, is not successfully tackled.

Cases of this peculiar "blindness" so far encountered, can be conveniently
divided into two classes depending upon the complexity and extent of the abnorma-
lities :—

Firstly, those in which the calves are born blind, the eyes being apparently
quite normal in size, shape and structure and showing no abnormal growth which
might explain the absence of visuality. Briefly speaking, these are cases of amau-
rosis and they appear to be far commoner than the other variety.

Secondly, those in which various sizes of teratomatous growths involving vary-
ing extents of the external eye and palpebral fissure are discovered, associated with
different grades of rudimentary eyeball, which are definitely related to the defect of
sight; briefly, cases of teratoma blindness (Plate XXI, fig. 1).

It is not clear whether the cases of calves being born blind with apparently
normal eyes and those which are born bind definitely as a result of the pressure
exerted by the dermoid teratoma on the eye have the same origin, but Dr. Darling,
Chief Officer of the Imperial Bureau of Animal Genetics, to whom reference will

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