Selenium and Immunity

A look at selenium and how it improves immune health in livestock

Posted by Brooke Loeffler on Dec 12, 2022 9:56:14 PM

What Is Selenium?

Selenium is a metalloid mineral that is found in the Earth’s soil. From there, selenium enters the food web by being absorbed by plants, and then ingested by animals. When eaten in the right amounts, dietary selenium has many proven health benefits, especially for the immune system.

Selenium And Immunity

Selenium is an you have probably heard the term antioxidant before, but let’s take a closer look so we can see selenium’s specific role in the immune system.

Oxidative Stress

The body is constantly turning molecules of food, water, and air into chemical energy to power itself. As these molecules are broken apart and metabolized for energy, pairs of electrons are broken apart as well. Molecules with unpaired electrons search the body, seeking out another electron to complete itself. These molecules are known as free radicals

Free radicals are normal byproducts, but can build up to harmful levels and damage healthy cells in their quest for electrons. Oxidative Stress occurs when too many free radicals are causing cellular damage. A body in oxidative stress is at higher risk for viral infections, inflammatory diseases, cancers, and other degenerative diseases.

Antioxidants and Selenoproteins

Antioxidants, like selenium, keep excess free radicals in check and protect cells from oxidative stress. They accomplish this by neutralizing free radicals with the electron they need.

Selenium how antioxidants work

Once ingested, dietary selenium also becomes incorporated into at least 25 different proteins. These selenoproteins regulate the immune system and prevent it from harmfully over-reacting. According to the National Institute of Health

“Dietary selenium (Se), mainly through its incorporation into selenoproteins, plays an important role in inflammation and immunity. Adequate levels of Se are important for initiating immunity, but they are also involved in regulating excessive immune responses and chronic inflammation.”

Selenium Deficiency

Did you know that most North American soils are deficient in selenium? Here is an interactive soil selenium map from the United States Geological Survey to find your county’s soil selenium levels. Symptoms of selenium deficiency vary from species to species and life stage as well. Oregon State University (OSU) Ag Extension lists the following symptoms for common livestock:


  • Poor calf health
  • Decreased immune function
  • Failure to thrive
  • Uterine infection
  • Mastitis
  • Retained placenta
  • Reduced fertility in cows and bulls


  • Un-thriftiness (failure to grow or put on weight)
  • Growth depression
  • Decreased twinning
  • Immunosuppression
  • Increased susceptibility to bacterial and viral infections


  • Similar symptoms to cattle and sheep


  • Delayed or reduced immune response to vaccination
  • Decreased immune function
  • Myopathy, difficulties in locomotion, suckling, swallowing, respiration, and cardiac function

In addition to these symptoms, livestock biopsies after death typically show white muscle disease. Veterinarians and nutritionists can perform blood tests, liver biopsies, and even milk tests in lactating livestock to help detect selenium deficiencies. 

How to Start A Selenium Supplement Program

Selenium is essential, but only required in trace amounts, in fact over 5 mg per day can be toxic for some livestock. According to OSU the following selenium amounts are recommended per head each day:


  • Calves (0-30 days): 0.1-0.25 ppm
  • Older than 30 days: 0.12-0.35 ppm


  • Lambs-adults: 0.12-0.3 ppm


  • Kids-adults: 0.17-0.3 ppm


Selenium supplements for Livestock

Here are some best practices for beginning a selenium supplement program:

  1. Test your soil’s selenium levels: Try Redmond's Soil Test Kit for fast and easy results! 
  2. Test your feed and forage: Find your area’s local cooperative ag extension and make note if your feed was grown in a selenium poor area.
  3. Animal health check: Your veterinarian and/or nutritionist can conduct possible blood tests and/or liver biopsies, or take milk samples for lactating animals.
  4. Introduce selenium mineral supplement to livestock: follow recommended feed ratios.
  5. Monitor your animals and enjoy the health benefits!

Selenium Supplements From Redmond Minerals

Here at Redmond Minerals, we are proud to share the richness of our Jurassic Era mineral deposit in central Utah. Our mineral program has been supporting healthy farms for over 50 years. With over 60 trace minerals, our products help animals, and the soil they live on, thrive.

Selenium and Immunity-04-2

Redmond Minerals can help improve the nutrient density of your forage, especially if you live in mineral deficient areas. For livestock health, our selenium fortified mixes (see below) are easy to incorporate into your feed program, and your animals will love it! We also offer a wide range of customizable premium mineral mixes to match the exact needs of your herd. Click below to learn more about our selenium fortified products:

Selenium 30 Block

Selenium 90 Block

Selenium 30 Granules

Selenium 90 Granules

Give us a call today at 866-709-3192 to learn more about how Redmond can help!

© 2021 Redmond Minerals Inc.

Back To Top