Different subtypes of Listeria monocytogenes were isolated from various ani
mal and environmental samples during an episode of increased mortality on a
fallow deer (Dama dama) farm. During a 4-wk period, six fallow deer died,
including four does, one fawn, and one adult buck. Prior to death, one of t
he does had exhibited central nervous system signs characteristic of lister
iosis. Postmortem examination of the six deer showed no histologic changes
typical of listeriosis. although inflammatory changes were present in sever
al organs. Different subtypes of L. monocytogenes were isolated from brain
samples from six deer, from fodder and soil from the deer feeding area, and
from Faces of some healthy animals on the farm. Listeria monocytogenes, wh
ich was frequently isolated in the environment of the farm, was considered
the probable major cause of mortality in these fallow deer.