August 31, 2026
Blog
Ridley Block Operations is proud to introduce a second FDA-approved, medicated Crystalyx® formula called Crystalyx® Iono-lyx® R800. This is a 4% phosphorus mineral formula containing monensin, widely known by the brand name Rumensin®. This formula is the result of several years of working with the FDA’s Center for Veterinary Medicine (FDA-CVM). The new Iono-lyx R800 free-choice medicated formula is approved under NADA 141-621. It is the only low-moisture block (LMB) containing Rumensin that is approved for free-choice feeding.
The new Rumensin Iono-lyx R800 block has two label claims:
For increased rate of weight gain and for prevention and control of coccidiosis caused by Eimeria bovis and Eimeria zuernii in growing beef steers and heifers on pasture (stocker, feeder, and slaughter) and replacement beef heifers on pasture.
This new technology builds on the success of Crystalyx® Iono-lyx® B300, the first LMB to contain an ionophore. Launched 22 years ago, this time-tested solution is a protein-based block formula with 28% crude protein and lasalocid, brand name Bovatec®.
The label claim for Iono-lyx B300 is:
For increased rate of weight gain in pasture cattle (slaughter, stocker, and feeder cattle and beef replacement heifers).
These two products are called “Iono-lyx” as they both contain an ionophore. An ionophore is a feed additive that changes rumen fermentation by selectively controlling certain rumen bacteria, helping cattle use energy and protein from feed more efficiently. Ionophores are also helpful in controlling coccidiosis. In beef cattle, the best-known ionophores are Rumensin (monensin) and Bovatec (lasalocid).
Crystalyx Iono-lyx LMB supplements are in a class of their own. Research on grazing beef cattle has shown that the high level of molasses in the LMB attracts more of your herd to consume the supplement on a consistent basis. This means a larger percentage of your herd actually consumes the supplemental nutrition you purchase and provide. Now, that nutrition can include an ionophore. Adding to the convenience, you don’t need a veterinary feed directive (VFD) to feed Rumensin or Bovatec.
Together, these Iono-lyx supplements constitute a year-round program, offering robust and consistent support for your herd:
Crystalyx Iono-lyx B300, a protein formula containing Bovatec, is for use on moderate to low-quality forages in the fall and winter.
Crystalyx Iono-lyx R800, a mineral formula containing Rumensin, is for use on high-quality forages generally fed in the spring and summer.
When evaluating Iono-lyx R800 for your operation, consider these five main features:
Iono-lyx R800 contains 800 grams per ton of Rumensin. Data in the Rumensin Free-Choice Efficacy master file (NADA 095-735) indicates that you can generally expect about an 11% improvement in rate of gain in growing beef cattle and replacement heifers on pasture. Four ounces of this R800 formula will provide 100 milligrams of Rumensin.
Iono-lyx R800 is an LMB containing 4% phosphorus and 4% calcium. This is a stand-alone mineral formula, perfect for supplementing the mineral and vitamin needs of your grazing beef steers and heifers during the spring and summer months while also providing Rumensin on a daily basis.
The copper, zinc, manganese and cobalt in Iono-lyx R800 are 100% sourced from Bioplex® organic trace minerals, which support greater trace mineral retention and tissue reserves. Optimal trace mineral nutrition is key to supporting weight gain on summer grass. Additionally, yearlings entering a feedlot will benefit from having been on a great trace mineral program prior to the stresses of shipping, receiving, sorting and handling.
Iono-lyx R800 is labeled for prevention and control of coccidiosis in growing beef cattle. There is no easier or more effective way to control coccidiosis in grazing beef cattle than with a free-choice supplement block containing Rumensin.
Iono-lyx R800 is a self-fed supplement. It greatly reduces the need for daily attention to the nutritional needs of your herd. A properly stocked set of 200-lb. Iono-lyx R800 plastic barrels should last about four weeks. This gives you the flexibility to check your cattle when and as often as you want. Even if you’re busy with other chores, Crystalyx Iono-lyx R800 is continuously supplementing your cattle, 24/7.
When evaluating Iono-lyx B300 for your operation, consider these four main features:
Iono-lyx B300 contains 300 grams per ton of Bovatec. Years of data in the Bovatec master file indicate that you can expect about a 10% improvement in rate of gain in growing beef cattle and replacement heifers on pasture.
Iono-lyx B300 contains 28% crude protein. Most of our fall- and winter-grazed forages will be short on protein for growing cattle. Iono-lyx B300 can effectively supplement that protein requirement in addition to providing Bovatec. This is an excellent product for wintering spring-calving replacement heifers or weaned calves that you plan to graze as yearlings the following summer.
Iono-lyx B300 strategically replaces 25% of the standard supplemental inorganic trace minerals with Bioplex organic trace minerals, which support greater trace mineral retention and tissue reserves. Optimal trace mineral nutrition is key to supporting weight gain for grazing animals. Your replacement heifers will benefit from having been on a good trace mineral program prior to and through the breeding season.
Finally, Iono-lyx B300 is a self-fed supplement. It greatly reduces the need for daily attention to the nutritional needs of your herd. A properly stocked set of Iono-lyx B300 barrels with yearlings or replacement heifers in a pasture should last about two weeks. This gives you the flexibility to check your cattle when and as often as you want. If you are busy with other chores, Crystalyx Iono-lyx B300 is always there for your cattle, 24/7.
Crystalyx brand supplements are an excellent way to provide consistent, controlled intake of ionophores such as Rumensin and Bovatec, as well as protein, vitamins, minerals and other necessary nutrients that can be deficient in your forages — and, as self-fed supplements available to your herd 24/7, these solutions optimize your profitability by offering considerable savings in time, labor and equipment.
