Quote: "Since there would be no benefit to putting in higher than guaranteed amounts, it's likely the percentage isn't higher than the guarantee" This statement is misleading because it assumes that everything in the feed is an "added ingredient" The truth is they don't account for what comes naturally in the grains. Grains have mineral content, high or low, depending on the soil it is grown in. The feed companies use "book values" for calculating the mineral and vitamin content. The book values assume that all grains of the same species have the same mineral content. Their "book values" are totally outdated (40 years old)because they were written when grains were only grown in a few midwestern states with low selenium soils. I have found out that most of our grains are now coming from South Dakota and Nebraska (toxically high Selenium soils) and being shipped everywhere because they are cheaper. Recent test results show the Selenium content of these grains are toxically high and will make your animals have hoof problems at the very least, and the rest of the symptoms can cause everything from agressive behavior, diabetes, liver problems, etc.. the list is a mile long. The feed companies have no idea the real selenium content of their feeds because they don't test for it. They are hoping you don't figure it out. Then on top of that they are adding more selenium. They add the maximum allowed by law with no regard to what is already in the grains or what each age or species of animal may require. Animals grazing in high selenium soils get selenium toxicity all the time. But those of us with no experience with selenium wouldn't think that cracked hooves or laminitis is related to reproductive problems. The truth is they can be related, your animal may only have one symptom or many symptoms, it all depends on where the selenium decides to come out. Last year I lost 100 sows due to feet and leg problems due to the selenium content of the grains from LOL/Purina feed. Check out this brochure, just take out the word "pork" and put in "horse" you will get the picture. This is a recent brochure put out at the request of the National Pork Board because of what myself and other animal owners have discovered. Now I want to get the word out to more people. http://www.pork.org/documents/porkscience/selenium%20toxicity.pdf You can contact me for more information. qbarfarm@viclink.com