How can I tell if my mare is suffering from selenium toxicity?

Hoof Nutrition Intelligence is a twice-a-month web segment that is designed to add to the education of footcare professionals when it comes to effectively feeding the hoof. The goal of this web-exclusive feature is to zero in on specific areas of hoof nutrition and avoid broad-based articles that simply look at the overall equine feeding situation.

Below you will find Part 1 of the latest question and answer installment that you can share with your footcare clients.

Q: How can I tell if my mare is suffering from selenium toxicity?

By Mike Barker

A: Selenium, a key trace mineral in a horse’s diet, also can cause major issues if given in excess of 2 to 3 milligrams per day. This can be easy to do if a horse living in a selenium deficient area is given a selenium supplement and the mineral is added to the feed. 

Then, if forage is brought in from an area that isn’t selenium deficient, that horse will end up with three sources of selenium and be at risk of toxicity.

Six signs of selenium toxicity that a farrier might notice include:

1 Lameness.

2 Hoof defects and poor hoof wall structure.

3 Horizontal hoof wall ridges.

4 Hoof cracks.

5 Crusty coronet band.

6 Hoof wall invaded by bacteria or fungi.

Mike Barker is a product representative with Life Data Labs in Cherokee, Ala. This information is taken from “How Nutrition Affects the Horses’ Hoof,” an article that appeared in the April 2020 issue of American Farriers Journal.

Click here to read part 2 of the March 15, 2020 installment of Hoof Nutrition Intelligence: Can other nutrients interfere with feeding biotin? Click here to read more installments of Hoof Nutrition Intelligence.