While we generally hear of the need to supplement normal diets with selenium ("white muscle disease"), there is an equal danger from the ingestion of too much selenium. This can be from soils and plants in certain geographical. Some plants can also cause acute selenium poisoning in any circumstance. This complex problem cannot be addressed in detail here.
Acute poisoning can lead to death in a few hours. Labored respiration, frothing from nostrils, dilated pupils, loss of hair from tail, sloughing of hooves, elevated temperature, unsteady gait. Chronic "blind staggers" type: wander into objects, impaired vision, poor appetite, throat and tongue paralyzed, subnormal temperature, respiratory failure, death. Chronid "alkali dusease" type: problems with joints, liver, heart, anemia, enlarged abdomen, crackling and/or deformity of hooves, lameness, dull, loss of hair. A "garlicky" odor of the breath is usually present in any type of selenium toxicity.
Consult vet for blood level evaluation and therapeutic measures.
Because this problem is so much of a local issue, consultation with your local extension agent can be very helpful.
Use selenium enhanced salt only when advised by local vet or extension agent. Withdraw immediately if any of the above symptoms occur and re-evaluate situation.
Univ of Prince Edward Island
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