222                     Rhinosporidiosis in Equines

The animal was brought to the hospital as it had audible breathing and
there was a slight bloodstained mucus discharge from one of the nostrils. The
Veterinary Assistant Surgeon while examining the affected nostril found a
small growth in the anterior part of the nasal cavity and he removed it.

The growth was about one inch long and half inch high and on naked eye
examination, it presented a cauli-flower-like appearance with a soft irregular
surface. When examined under a hand lens, it presented numerous pale
white specks embedded in soft tissue, which on histological examination proved
to be cysts or sporangia of Rhinosporidium.

Histologically the growth appeared to be identical in every respect with
the one described by Krishnamurti Ayyar. It was covered with stratified
squamous epithelium which presented an irregular outline and was in places
thrown into folds. In the superficial layers of the underlying highly vascular
sub-epithelial connective tissue were present large numbers of sporangia in
various stages of development. They were either oval or spheroidal in outline
and each was enclosed in a capsule which was thicker in the young than in the
older sporangia.

Inside each sporangium were present numerous spores in various stages of
development, the fully formed ones being usually in the centre and the small
ones at the periphery. In a few the fully-formed ones were situated at one
pole and the small ones at the other. The spores were enclosed in a thick
chitinous envelope with granular bodies inside them. Those bodies are consi-
dered by some to be refrangent spherules and by others to be sporules or
sporozoites.

As the sporangia grew older, they increased in size and ultimately pressed
upon the overlying epithelium which gradually diminished in thickness and
ultimately burst along with the capsules of the sporangia, thus enabling the
spores to get discharged on the surface of the nasal mucous membrane.

The case described in this paper is the second of its kind to be discovered
in a horse in India. Careful enquiries failed to reveal the existence of more
cases in the locality.