What is a safe level of selenium?

How do I know if my horse is low on selenium?

Horse Nutrition: Selenium.

Selenium is an essential trace mineral that helps your horse maintain healthy skin, blood, muscle and bone. As a member of the Se family of nutrients, selenium also plays a role in immune function and thyroid regulation. You can learn more about this important trace mineral in our Selenium FA?

Horses that are fed a poor-quality forage will often have selenium levels that are too low to ensure optimal health. A common sign of selenium deficiency is pale hooves and/or hair. If your horse has these symptoms, it is a good idea to test his blood selenium levels. There are two ways you can do this:

In the Blood. Your vet or a commercial lab can test your horse's blood selenium levels using a swab from his hindquarters or other body parts. It takes only a few minutes to swab your horse and send the sample off for analysis. This is a good option if you are a novice horse owner or do not have access to a commercial lab.

Another alternative is to ask your vet to test your horse's blood selenium levels. Your vet may use a simple swab from the center of your horse's tongue and then send the sample to the lab for analysis.

In the Urine. Your vet or a commercial lab can test your horse's urine selenium levels using a simple dipstick. If you are planning to test your horse's urine, be sure to collect the urine in a clean, wide-mouth bottle. You can dilute the urine with water if you want to get more accurate readings.

What is a toxic level of selenium for horse?

I have a 4 year old gelding who is showing signs of selenium toxicity.

He is currently eating his daily dose of Taurine, and I think I know why he is showing signs of toxicity, but I want to be sure before I take him off it. He shows signs of excessive hair loss, skin conditions, and nervousness, just the typical signs of selenium toxicity. He has not been showing any signs of toxicity for months now, but I am concerned that this is due to selenium toxicity. I believe he has about 10-20 ppb of selenium in his blood at this time. He has been under a veterinarian's care for the last 4 months because of severe colic and a couple other issues. His bloodwork always came back with selenium levels between 20-30 ppb. The vet was not able to identify the cause of his colic issues, and no blood work came back abnormal for selenium. We changed to a new vet who has a better understanding of equine selenium levels and has suggested that I should wean him off taurine and transition him to a selenium rich feed, which has been a success so far. I am not sure if the selenium levels have dropped off since starting this new diet or if it is just a coincidence. I am a horse owner, not a vet, so I have no experience with equine blood work or anything like that. I just know that he is now doing well on the new feed, but I am still not sure if he is selenium toxic or not.

Does anyone know how many ppb of selenium is considered toxic for horses? What about a horse who is showing signs of toxicity, but has not reached a toxic level of selenium in his blood yet? It's pretty easy to determine if you're in trouble, you don't need a vet or even bloodwork to do it. You need a few things. First, a good diet with a very low concentration of selenium, and the best place to find it is a grain free, high fiber diet like a natural hay. Selenium concentrates in grains. If you feed hay or pellets, they can be high in selenium, and you'd need to remove the grains, including hulls.

The second thing you need is some way to monitor your horse.

What is a safe level of selenium?

Selenium has been studied in the past as a nutritional supplement, but now is being investigated more and more as anticancer agent. However, this chemical is toxic at high doses. Therefore, it is important to know the safe levels of selenium that we can take.

To find the safe levels of selenium, we need to look at what the National Toxicology Program (NTP) found in the 2024 NTP Monograph on Selenium and Cancer. In this report, the NTP said that No adverse effects were observed in rats given selenium concentrations up to 3 mg/kg/day. In other words, the NTP concluded that the selenium level in the diet was not toxic.

To determine the safe level of selenium for humans, we need to look at the NTP's 2024 report, Effect of Selenium on Carcinogenesis. In this report, the NTP looked at selenium and cancer in rodents, specifically in mice and rats. The NTP concluded that selenium had a pro-carcinogenic effect in both species. The NTP said that This study shows a direct relationship between selenium supplementation and colon and bladder cancers in mice. The NTP recommended that selenium be added to rodent diets only at levels of 0.5 to 1 mg/kg/day. The NTP said that, At levels of 2 mg/kg/day or greater, selenium is carcinogenic.

In order to understand what the NTP is telling us about the safe level of selenium, let's look at the numbers. The NTP recommends that selenium levels in the diet be 0. This translates into 5 to 10 ppm (micrograms per kilogram) in the diet.

The NTP recommends that selenium levels in the diet be 2 mg/kg/day or higher. This translates into 20 to 30 ppm in the diet.

At a selenium level of 0.5 to 1 mg/kg/day, the NTP found that selenium was not toxic to rodents.