More reports on negative effects of excess iron on horses

December 1, 2011

On Nov. 11, 2011, Dr. Mehmet Oz probably made a few enemies in the multivitamin world when he recommended all but women of child-bearing age stop taking multivitamins containing iron because of a recent study that showed excess iron caused problems in the aorta.

In trying to find the study (which I never found), I came across other interesting reports on iron and eventually searched for items related to horses.

An article in “The Horse Journal” written by a veterinarian who isn’t identified by name says chronic excess iron leads to deficiencies in zinc and copper, leading to skin problems, tendon and ligament weaknesses, faulty production of joint cartilage and foot problems including laminitis. Excess iron also can cause anemia by creating a copper deficiency.

In trying to find out how common excess iron is, the vet turned to Uckele Animal Health, which does hair mineral analysis on horses. The vet says Uckele reported that high iron levels are one of the more common abnormalities it finds in horses.

My horses had a hair analysis done in 2004 after Angel foundered, though I remember my vet didn’t put too much stock in it, and I don’t know if it was the same type of test that Uckele does. It was done by a different company, and that company doesn’t appear to be in business now based on a quick online search.

We tested three horses: Angel (foundered in 2004), Goldie (foundered in 2002) and Kurt (white horse, completely normal at the time). What we noticed at the time was that Goldie and Kurt both had really unhealthy levels of arsenic (I have arsenic-treated wood for fencing), but Angel did not. And while I explained the difference in Angel by saying Angel had lived elsewhere for three years on a lease, Angel was the one that had just foundered, prompting the hair analysis, so it was hard to pin laminitis on elevated arsenic levels, especially since Kurt with his elevated arsenic showed no signs of laminitis.

As I review these old hair tests now and look at the iron levels, Kurt’s level was normal, Goldie’s was high at 410 ug/g and Angel’s was excessively low at 46. The normal range was 60 to 400.

Goldie’s copper was too high and her zinc was normal. Kurt’s copper and zinc were both too high. And Angel’s copper and zinc were both normal. Very unhelpful.

Well, at least Goldie’s iron was high and she foundered, and Kurt’s iron was normal and he didn’t founder. Can’t explain Angel.

The vet in the “Horse Journal” article gives a case study of a racehorse that was sound but nonetheless had many health problems, including dry skin and skin infections, tendinitis, desmitis and tying up. And his black hair was rust-colored, looking sun-bleached. When the horse was tested by this vet, the blood iron and ferretin levels were massively elevated. The horse eventually improved with supplementation of high doses of vitamin E, selenium, manganese, zinc and copper. And the vet notes that this problem will be with this horse for life; he will need the correct supplementation.

I have had nothing but skin problems with my horses during all the laminitis. Completely unexplained open wounds all over, especially in Goldie and Angel, and, while people have tried to convince me for years that it was sweet itch, I never really bought it. Also, Angel’s black hair was almost always rust-colored while here; she didn’t get enough sun the last couple years to explain how bad her hair looked. This is an interesting revelation.

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