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Seasons change: Spring grasses and grass tetany risk

With the NFL football season now over, some of us look forward to the Major League baseball season in April. Maybe some of you are watching the XFL football games at present, but there is one more season that is about to start soon. While perhaps not as exciting as the aforementioned sporting events, grass tetany season can certainly be more impactful on your profitability as a cow-calf producer. 

Problem cause

Rapidly growing cool season grasses will not often have enough available magnesium to support a cow’s needs. Grass tetany is more prevalent in cool springs or after a cool stretch of weather in a wet spring. Pastures that have been fertilized also seem to be more prone to grass tetany. Cows are most vulnerable to grass tetany once they calve and begin to lactate. Their requirement for magnesium will almost double at this time. It is actually quite common to hear that the best milking cows are the ones that go down with grass tetany. This is because their magnesium requirement is higher than a cow with lower milk production.

The precipitation forecast

A look at the three month precipitation outlook shows that most regions that typically have issues with grass tetany will likely have ample moisture this spring.

The temperature outlook

A glance at the three month temperature outlook shows that the northern plains will have cooler than normal temperatures to go along with that extra precipitation. It would appear that grass tetany problems are certainly in the cards for the spring of 2020.

Problem fix

Cattle cannot store any appreciable amount of magnesium in their body, so we must provide supplemental amounts daily. While magnesium oxide is generally considered a good source of supplemental magnesium, it has one important drawback in that it is very unpalatable.

A better solution

So, what is a cattleman to do when you need to provide a daily dose of something that tastes bad? Fortunately, CRYSTALYX® is primarily composed of good-tasting molasses. CRYSTALYX High-Mag supplements have long been the best way to provide a daily dose of bad tasting magnesium oxide to grazing cattle. Our supplements are available 24/7 and the molasses easily masks unpalatable ingredients. You should begin providing CRYSTALYX High-Mag supplements approximately one or two weeks before you suspect any bouts of grass tetany. This is not to build up magnesium stores, but to make sure cattle are consistently consuming the product when grass tetany season arrives in your pastures.

Specific products

CRYSTALYX offers several high-magnesium formulas for a variety of grazing situations: 

  • Super-Mag™ is a balanced magnesium supplement with 12% crude protein, for general use. 
  • Blueprint® 17 Mag is a premium magnesium supplement made with 17% crude protein and is intended for situations where you need magnesium supplementation along with a total replacement of inorganic trace minerals. This product has been formulated with organic trace minerals to realize maximal performance from today’s advanced genetics.
  • ROLYX® Pro-Mag would be the supplement of choice if you also want to add fly control to your magnesium supplement. It contains 18% crude protein.
  • Hi-Mag Fescue-lyx® is a 20% crude protein supplement that is a great choice if you are running cows on endophyte-infected fescue.

If you have a copy of our new supplementation guide (released in January), you can find the Hi-Mag product columns (below) on pages 9 and 11.

CRYSTALYX is an extremely palatable supplement that is available to your herd round the clock during grass tetany season. With normal stocking rates (20-30 head per barrel), a set of CRYSTALYX barrels will last about two weeks. Whether it rains or snows, or while you are putting a crop in, or are busy with other chores, CRYSTALYX is there with your herd every day. Simply set it and forget it until it’s time for a new barrel!