Cow mineral supplements
Jeff Hall is a professor of veterinary science at Utah State University and is an expert on beef cow mineral supplementation. He says liver biopsies are one way to learn the success of your program. Here are some common questions he fields.
SF: How can I know if my mineral program is working?
JH: A lot of things you may think are health problems are really a result of nutritional deficiencies. For instance, these things could indicate your herd has deficiencies:
- Poor growth in some or all calves
- Poor disease immunity function
- Increased susceptibility to disease such as diarrhea or pneumonia
- White muscle disease in calves
- Poor conception in cows and heifers
- Lameness in bulls and cows
SF: What are common mineral deficiencies?
JH: Copper is number one. Sometimes, I’ll see 70% of the cows in a given area that are deficient in copper.
Selenium is next, with deficiencies in 10% of herds up to 70%, depending on the area. I’ve worked with herds in Arizona and found that up to 65% of the herds sampled have animals that are selenium-deficient.
Rarer deficiencies are seen in manganese, zinc, and cobalt. Some of these vary by year. After a drought, forages can be lower in zinc for up to two years.
SF: How can I test for mineral deficiencies?
JH: I’m a big fan of liver biopsies. If cows are deficient, you’ll see it in the liver. You can do it on cull animals or those that die by accident. Or you can do it at pregnancy check.
It’s done with a 6-inch needle, and the angle to hit the liver is important. Work with your veterinarian. If it’s done correctly, there’s no impact on the cow.
You can send biopsies to a lab for analysis. Lots of labs will do it, including the Utah Veterinary Diagnostics Lab (usu.edu/uvdl). Your vet or nutritionist can help you analyze the results.
You don’t have to biopsy every cow. If they’ve all been supplemented the same, you can get a good idea of your mineral situation with eight or 10 biopsies.
SF: Are mineral deficiencies increasing?
JH: Maybe. When money is tight, ranchers may stop supplementing. I try to show them how mineral supplements can make them money.
If you have a moderate mineral plan and upgrade to an excellent plan, I have no trouble telling you that every dollar invested will return you five. You’ll get a 2% to 4% improvement in breed-back rates and up to 15% when correcting severe deficiencies. You’ll get the most response in young cows that are still growing.
You’ll have fewer sick calves and less summer pneumonia issues. You’ll add 25 to 30 pounds per calf in weaning weights – sometimes more.
Beef herds are more productive today than they were a number of years back. You may crank out one-and-a-half times as much beef from your ranch. Has your mineral program kept up?
For most ranchers, the actual mineral intake is less than they think. If you feed a supplement that is to be consumed at 4 ounces per head per day and the cows are only eating 2 ounces, deficiencies may occur even though a good product is being provided.
SF: Is there a place for injectable minerals?
JH: In some cases, they are the only option. For instance, if cows are going to a remote summer pasture, injectable may be the answer. I prefer to get minerals into mama cows by good supplementation in a mineral feeder.