Sodium chloride (salt) should always be provided because cattle need more salt than what occurs naturally in forages.
Iron is an important component of red blood cells – enabling them to carry oxygen.
Bone formation and milk production depend on calcium and phosphorus.
Calcium and phosphorus are called macrominerals because they are required in fairly large amounts. Deficiency is generally not a problem because these minerals are present in high levels in many feeds.
Other minerals such as copper, iron, iodine, manganese, selenium and zinc are needed in very tiny amounts and are called trace minerals.
They are also very important to health. Adequate levels of copper, zinc, manganese and selenium, for example, are crucial for a healthy immune system and optimum reproduction.
Some soils and plants are short on various minerals, leaving feeds deficient. During the past two decades, USDA studies of blood levels for trace minerals in cattle herds found numerous animals deficient in these four important minerals.
Many livestock producers use supplemental minerals to augment cattle diets. These are often supplied in salt/mineral mixes provided free-choice.
Consumption is varied, with some animals consuming too much while others eat inadequate amounts or none. Other aspects of diet may hinder absorption by the body.
Because of this variability, some stockmen resort to individually dosing animals by drench, bolus or injection – to make sure cattle receive the necessary minerals.
In recent years, the value of injected trace minerals has been scientifically recognized as a reliable way to ensure that cattle receive them.
Storing the benefit
Dr. Lourens Havenga, chief executive officer of Multimin USA, Inc., says that when Multimin 90 was created it was based on the 2001 NRC requirements for cattle and actual absorption of minerals, recognizing proper ratios of copper, zinc, manganese and selenium.
Havenga points to several university studies that show the benefits of injected trace mineral products – looking at how rapidly these minerals are absorbed and how long they are stored in the liver.
Other studies have evaluated effects on calf health and reproductive performance when injecting cows before and after calving.
“Subsequent to launching our new product, I also contacted researchers at Iowa State University to do additional studies,” says Havenga. Those studies showed that the injected product is absorbed rapidly.
“Trace mineral levels in the blood increase and reach a peak within eight to 10 hours of the injection.
Most of the mineral that the animal doesn’t utilize is stored in the liver. We later had other studies done at Texas A&M that showed the product lasts (stored in the liver) for about two to three months, depending on mineral status prior to injection,” says Havenga.
“Another part of the research done at Iowa State looked at enzyme responses. These start immediately but, by 14 days after injection, significant changes were confirmed and peaked around day 30.
This is why we recommend that producers use this product 30 days in advance of stresses, calving or breeding, especially for enhancing reproductive performance.
You can use it earlier than that, such as at preg checking, but shouldn’t use it much closer to these events because cattle might not get full benefit,” he explains.
Calving and breeding
A Texas A&M study in beef cattle came up with additional data regarding differences in cattle performance when injected with trace minerals.
An experiment was conducted to determine effects of providing pre-calving and pre-breeding injections of trace minerals and vitamin E on reproductive performance of beef cows and on health and survival of their calves.
In this study, 67 crossbred cows at the Texas A&M Beef Center were randomly assigned to a control group or trace mineral/vitamin E treatments. The treated cows were given injections 30 days prior to the start of calving and again 21 days prior to the start of breeding.
The trace mineral injections effectively improved copper levels (liver) and selenium (blood levels) compared to the non-treated cows.
The treated cows had significantly higher liver concentrations of copper than the controls, remaining higher for 161 days after the last injection.
In the Texas study, more cows became pregnant in the treated group; cows in the control group were 2.4 times more likely to be open.
“This showed that if you use the product strategically, these two injections can keep liver levels elevated in the cow for almost a full production cycle.
We ended the trial at 256 days, just before the cows started calving again the next season,” says Havenga.
“The producer benefit in the Texas A&M study was that we increased calving percentage, and those cows also calved earlier.
The cows treated with injected minerals bred back quicker and calved six days earlier, on average, than the untreated cows,” he says.
A recent study at Kansas State University used all of their beef cows, in both university herds, looking at the benefit of using Multimin 90 at preg check (three to four months before calving) and again 30 days prior to breeding, to evaluate the effects on reproductive performance, bodyweight change, BCS change in beef cows and growth of suckling calves.
Calves were injected at birth and again at branding time.
Cows grazed native grass pastures and had trace-mineral supplements and white salt available free-choice before and during the study.
Bodyweight and condition from the start of the study until calving (and from AI to weaning) were similar in the treated and untreated groups, but the cows receiving the injected mineral gained more weight from calving until AI and conception rates (to fixed-time AI) were greater in the mineral-treated cows.
No signs of mineral deficiency were observed in cows before or during the study, but the average pre-treatment serum concentrations of manganese, copper, selenium and zinc were below normal range – in spite of free-choice trace mineral supplements for 12 months before the study began.
The researchers determined that a notable portion of their beef cow population may have been marginal to slightly deficient in these minerals.
They speculated that the trace mineral status of individual cows may not have been optimal because of non-consumption or erratic intake of free-choice supplement.
Building immunity
Another study at University of Florida (results published in May 2012) looked at the benefits of using injectable trace minerals in conjunction with modified-live virus vaccines given to beef calves.
Improving trace mineral status of stressed calves had earlier been shown to decrease illness and improve feedlot performance (via improved feed efficiency).
The enhanced immune response to vaccinations (shown in the recent study) may be a contributing factor in the positive health and performance reported in previous studies.
A study at Iowa State University, reported in July 2012, looked at the impact of injected minerals on carcass quality in feeder cattle.
Adequate trace mineral status decreases shrink during shipping and improves marbling score in feedlot steers.
The study concluded that utilizing an injectable trace mineral at the start of the finishing period improved average daily gain, bodyweight and beef quality by improving hot carcass weight, larger rib-eye area and greater marbling score.
Making sure cows have adequate levels of trace minerals during pregnancy ensures normal bone formation and immune system development in the growing fetus and also enables the fetus to have adequate stores of these important minerals in its liver.
This gets the calf off to a good start. Some stockmen give calves injections during the first days or weeks of life or at branding time.
Ideally, you need to make sure the calf has peak levels (and is not deficient) at the time of vaccinations, in order to mount strong immunities. Unless a calf has adequate trace mineral status, vaccination may not protect him against disease.
After this year’s drought, many calves coming into backgrounding operations and feedlots may have compromised immune systems and won’t respond adequately to vaccinations.
Injectable trace minerals can help ensure a healthy immune system, complementing vaccinations or antibiotic treatments. 
PHOTOS
TOP: One study shows use of injectable trace minerals along with a modified-live vaccine played a contributing factor toward decreased illness and feed efficiency.
BOTTOM: Kansas State professor KC Olson, right, along with a participating student work cattle in a study to determine the various impacts of injectable trace minerals both pre-calving and pre-breeding. Photos courtesy of Multimin
