How do I know if my mare has
been exposed?
It is important to have all abortions
investigated by pathologists to
identify cases of EAFL so that
you know what you are dealing
with. This also allows you to make
decisions about managing your
pregnant mare herds as well as
individual mares. Reducing the
risk of EAFL is currently based on
control of the caterpillars in the
environment and reducing exposure
risk. These measures have been
shown to be effective at reducing
EAFL.
•investigate the history of mare
breeding and incidence of pregnancy
loss on your farm learn what the
different nesting forms of the
Processionary caterpillars (Figs. 4 –
9) are, and if possible, get someone
to show you both egg masses and
nests so you know what you are
looking for
•inspect your property carefully to
identify Eucalypts and Acacias that
are known hosts of Processionary
caterpillars, remembering that
not all trees associated with
Processionary caterpillars have
been identified
Figure 6. Pale coloured egg masses of the ground-nesting form.
Image: Julianne Farrell
•inspect all trees for the presence
of egg masses and nests in paddocks
where you are planning to house
pregnant mares between February
and September. Also inspect trees
in adjacent land within 200-400
meters of the fence line
•Inspections for egg masses should
be done from November to December
•Inspect for nests from January to
February
•Remove and dispose of all egg
masses and nests that you can –
refer to http://eafl.net.au/about-
eafl/risk-management-for-mares/
for more detailed information
•Mark trees that have egg masses
or nests so that you can have the
species of tree identified and also
so you can check these trees for egg
masses and nests early in the next
season; record this information.
Identification by a botanist requires
reproductive material (flowers,
pods, buds and leaves) from the
tree, not just leaves.
Figure 7. Primary ground nest at the base of a tree and a secondary nest under surface
debris about 1m away, shown within the red circles in the image.
•If removing and disposing of trees
that are known to be infested with
Processionary caterpillars each
year, care must be taken not to
disperse any material still present
on or around the trees. This should
be done when there are no pregnant
mares in the vicinity.
•Be aware of the health risks of
handling Processionary caterpillars,
egg masses and nest material, and
implement appropriate workplace
health and safety procedures -refer
to http://eafl.net.au/
Figure 8. Trunk nest on Eucalypt.
Image: Julianne Farrell
Page 20 • The Australian Quarter Horse Magazine • July • August • 2017