Agriculture Reference
In-Depth Information
evolution. Indeed, over 75% of affected horses die within 72 hours after
presenting clinical signs resulting from the severe degeneration of
different muscle groups involved in breathing, posture, or the heart
muscle.
There are fewer than ten years, this disease was unknown from the
veterinary and equestrian field. More than a dozen European countries are
now concerned by this specific disease of equines. Recently, atypical
myopathy has also been recognised in the USA.
Atypical myopathy does not show characteristics of a contagious
disease but its occurrence is linked to specific environmental conditions
and thus, it emerges in the form of an epizooty: several grazing horses are
hit by the disease at the same time and in different regions or even in
different European countries. The clinical outbreaks are reported mainly
in autumn and spring.
Occurrence of the clinical syndrome in a horse implies that
appropriate circumstances to the onset of the atypical myopathy were
present in the host and/or in its environment. Large European
epidemiological investigations have identified those circumstances, thus
defining risk factors.
These factors are related to the host (
e.g.
host susceptibility due to
age), timing (
e.g.
season), location (
e.g.
local geological and ecological
factors) and other miscellaneous features (
e.g.
type of feed, climatic
conditions, the use of the horse).
This review describes management practices at the horse and pasture
level in order to reduce the incidence of atypical myopathy in grazing
horses.
Keywords:
Pasture; Epidemiology; Prevention; Atypical myopathy
1.
I
NTRODUCTION
1.1. Epidemiology
Atypical myopathy (AM) is an acute and severe muscle pathology that can
lead to the death of affected horses in a few days. In the past, AM was only
sporadically encountered, but since the last years it has been recognized as an
emergent disease (Votion and Serteyn 2008; van Galen et al. 2010). Several
large outbreaks have taken place in Belgium (Delguste et al. 2002; Votion et
al. 2007), Germany (Brandt et al. 1997) and France (Puyalto-Moussu et al.
2004) and the disease has now been recognized in a dozen of European
countries (Palencia and Rivero 2007; Votion and Serteyn 2008; Votion et al.
