278
Paratuberculous Enteritis of Sheep
whitish opaque and firm tubercles of more or less a solid consistency. The
mesenteric lymph glands and those lying adjacent to the colon were enlarged
and on sectioning exhibited a soft dark grey surface without any caseous
material.
LABORATORY FINDINGS
The material from ewe No. 490 was examined at the farm veterinary
hospital laboratory and the material from ewe No. 812 was despatched to the
Imperial Veterinary Research Institute, Mukteswar for examination.
Four smears prepared from the mucous membrane of the ileum, colon,
and rectum were stained with Ziehl-Neelson method and examined. Small
groups of acid fast bacilli, which were indistinguishable from paratubercle
bacilli, were detected. The bacilli were short, slender and straight or slightly
bent. Club like forms, frequently showing a beaded appearance as described
by Howarth [1937], were not observed.
Smears made from the enlarged lymph glands also showed acid fast bacilli
of similar nature.
The report received from the Pathological Section of the Imperial Veterin-
ary Research Institute, Mukteswar, in respect of the material from ewe No.
812, which is reproduced below, confirmed our findings :
' Microscopical examination of smears from intestinal mucosa and
mesenteric glands revealed the presence of numerous acid fast organisms
morphologically indistinguishable from Mycobacterium paratuberculosis.
Histological examination of the intestines revealed lesions associated with
advanced Johne's disease '.
DISCUSSION
Johne's disease in sheep has been recorded but it is too early to say any-
thing about its actual incidence among flocks in India. It is also difficult at
this stage to attempt to judge the mortality from this disease but if the figure
of 5 per cent, as mentioned by McEwen [1939], holds true for India also, it
would mean that the disease must have a wider distribution than hitherto
believed. The possibility of sheep becoming infected from cattle has been
recognised but most workers, e.g. McFadyean and Sheather [1916] recorded
cases amongst sheep in farms where very few cattle were maintained and where
no history pointing to the occurrence of a case of Johne's disease amongst
cattle existed. Howarth [1932] cultivated the micro-organism from sheep
in California which had never come in contact with cattle. The inability of
McEwen [1939] to cultivate the bacillus from sheep as in the case of cattle
further justifies the probability that there are two different strains. At the
Government Cattle Farm, Hissar, however, both sheep and cattle are main-
tained and the occurrence of Johne's disease amongst cattle has been recorded
from time to time.
Since the ovine strain has been found to be infective for calves [McEwen,
1939], the detection of disease in the early stages before the clinical symptoms
become too apparent is of paramount importance for the prevention and
control of the disease. McEwen [1939] has been able to demonstrate Johne's
disease bacilli in the fæcal material but according to Howarth [1937] fæcal
samples from animals without diarrhœa are of no value for diagnosis. Accord-
ing to Houthuis[1932] the pinching of a piece of the mucous membrane of the