Sesquiterpene lactones and essential oils or monoterpenes are toxic to horses, but not to cattle, sheep, goats and wild ruminants under normal grazing conditions. The toxicity of sage varies considerably depending on growing conditions, and season, being most toxic in the fall and winter months.
Horses generally can eat small amounts of sage without problem. Sage poisoning occurs when the sage becomes the sole source of food such as in winter when sage is the only forage protruding above the snow.
There are many species of sage or sage brush in North America, with only relatively few of the species being a problem to horses that eat them in quantity. Artemisia frigida (fringed sage, sagewort)is invasive in overgrazed pastures and therefore can cause poisoning problems.
A perennial woody plant growing to a height of 4 feet. The multiple stems and leaves are covered with gray hairs giving the plant a silvery green appearance. The leaves are up to 4 inches in length, and are divided linearly into fine segments. The inconspicuous flower clusters are produced at the ends of the stems in the leaf axils.
Sand sage has the characteristic smell of sage.
Smell of sage on the breath, and in the feces. Appetite remains good.
Prevent further access to sand sage, and provide anutritious diet. Most horses will recover after 1-2 months depending on how badly intoxicated they became.
Horses exhibit abnormal behavior characterized by ataxia and a tendency to fall down or act abnormally to stimuli that would not normally have elicited such a response. Tying a horse to a fence, for example, will cause the animal to pull back violently, eventually throwing itself to the ground in panic. If left undisturbed, the animal will recover and will act relatively normal. Ataxia is particularly noticeable in the front forequarters with the hindquarters seemly normal. Some animals may circle incessantly, and others may become excitable and unpredictable. Sage poisoned horses maintain an appetite, and have a normal temperature, pulse and respiration.
The clinical signs of a sage poisoned horse can resemble those of a horse that has been poisoned by locoweeds. However, unlike "locoed" horses that will not recover fully, "saged" horses tend to recover in 1-2 months after they stop eating sage and are fed a nutritious diet.