Kent Tjardes, Ph.D.
Field Cattle Consultant, LOLPF
We can easily look at the price of mineral and intake to determine what it costs us to feed free-choice mineral supplements to our cow herd. However, we should also evaluate what it costs us not to feed a quality mineral supplement to our cows. We typically figure a mature 1100 lb cow will consume about 110 lbs of mineral each year. The costs can very depending on the level of phosphorus in the mineral and the addition of organic trace minerals, horn fly control (i.e. Altosid IGR), Aureomycin, etc. But on average you can plan to spend around $54/cow/year for Vitalix #7 Mineral.
Providing macro minerals, trace minerals and vitamins are very critical when it comes to getting your cows rebred as close to 60 days post-calving, as well as making sure she weans a heavy calf. By not feeding a quality mineral you can easily reduce the number of calves weaned per cow exposed by 5%, due to both cows being open and from calf death loss. In addition, you can also reduce the number of cows that are bred in the first 21-day heat cycle by 10%. With our current genetics, one heat cycle is equal to at least 50 lb of calf weaning weight. So this could cost:
a) Weaning weigh at 500 lb × $1.05/lb × 5% reduction = $26.25/cow exposed
b) 10% later calves × 50 lb/calf × $1.05/lb = $5.25/cow exposed
c) Bred cow at $1,000 – $540 cull value × 2% more open cows = $9.20/cow exposed
(5% more open cows = $23.00/cow exposed)
If you are not feeding a mineral supplement that contains higher levels of Magnesium in the early spring with lush grass to prevent grass tetany, the death loss could cost:
d) Cows valued at $1,000 × 3% tetany death loss = $30/cow exposed
In regards to your replacement heifers, the current figures from Harlan Hughes’s article “The Next Decade: Part III” in the February 2010 issue of Beef Magazine, the cost of a replacement heifer from conception to pregnancy checking is $1012. This value is adjusted for an 85% conception rate and a cull heifer credit of $0.90/lb × 813 lb. If you are not feeding a quality mineral and you reduce the number of replacement heifer that become bred it could cost:
e) 2% reduction in heifer conception rate = $18.50/heifer
f) 5% reduction in heifer conception rate = $32.91/heifer
In Summary, many times we concentrate on what it costs to feed a free-choice mineral supplement but we do not always figure out what it costs us NOT to feed mineral. Those costs for NOT feeding a quality mineral can easily be greater than $90/cow exposed based on reduced weaning weights, calf death loss, cow death loss, increase number of cull cows and higher cost of pregnant replacement heifers, for at least a 3:1 return on investment. This return does not even include the value that minerals have to stimulate the microbial populations, which has been shown by the University of Missouri to improve fiber digestion by about 5%, which allows you to also get more energy out of your forages.