It's Monday night and the football game is somewhere in the third quarter. You are really not sure how much time is left on the game clock because you have long since done the netal calculation of probable possession times and came up with the realizitation that your team could never overcome the 45-6 deficit. For some time now, the commentators have been droning on about the disappointing performance of your quarterback who has fewer passing yards than the punter and a completion percentage that matches your newly refinanced mortage rate.
It makes some sense that the quarterback would receive the spotlight as every offensive play brings attention to him and he is likely one of the highest-paid players on the team. Then to your amazement, one of the more enlightened guys with a microphone says, “Well, injuries on the offensive line certainly can’t be helping anything.” You think to yourself, REALLY. The quarterback has had less than two seconds to get rid of the ball before he gets crunched by some defensive Goliath. A football novice would realize that bad blocking would affect the quarterback’s performance. So often times people focus on one particular aspect of a subject to the extent that other attributing pieces of the puzzle are overlooked.
For several years now, the hunting world has acknowledged the benefits that a high-quality, highly nutritious food plot can provide to a deer herd. Most of the conversations surrounding food plots lead to a discussion concerning protein levels. Certainly, protein is a vital supplemental nutrient to all segments of the deer herd, but too many times, supplemental considerations begin and end with food plots and protein.
I was recently talking to a very intelligent ranch manager who was having issues with broken antlers. He said that he couldn’t understand why he was having so many issues as he was feeding a protein supplement.
I asked him, if he knew what the mineral level was in the protein supplement. He said that he wasn’t really sure there was any mineral in the supplement and that he wasn’t specifically feeding any additional mineral supplement. In fact, the response had the tone of “why does that matter.” When I explained that although protein is no doubt vital for antler growth, mineral is equally important, especially in the latter months; and it plays the largest role in antler density which directly affects antler integrity. He had never considered this, and again, this guy knows his stuff in terms of deer management.
Minerals have often taken a back seat to protein in terms of nutrients discussed in deer management and sometimes not even made the bus. The reasons for this are numerous, and range from a lack of knowledge to misunderstanding caused by a cornucopia of opinions on mineral. Lack of knowledge is understandable as we all have not been trained in nutrition. In general, there are two causes for the misunderstanding surrounding mineral.
First, there are several products on the market that are touted as mineral supplements but in reality more closely resemble an attractant. A product that contains primarily salt could be called a mineral as salt is indeed a mineral, but the product’s purpose would mostly be for attraction as a true mineral supplement would contain high levels of other minerals such as calcium, phosphorus, magnesium, etc. Salt alone will not help to increase antler growth or density.
The second reason for the confusion is that mineral requirement research, in the classic sense, is nearly impossible to do on a wild deer population. This type of research is conducted by selecting one mineral and depleting it from the diet while leaving the rest of the diet at optimal levels. Deficiencies are then noted and benefits are observed as you systematically increase the deficient mineral. The problem is that in order to get accurate results, the deer must only have access to the test diet which means that the only way to legitimately accomplish this is to perform the test on penned deer.
However, warehouse loads of research have been conducted on domestic ruminants such as cattle, goats and sheep proving that mineral supplementation increases body weights, milk production, reproductive efficacy, immune function and more. Because a deer’s mineral needs are at a minimum, equal to domestic livestock and more likely greater, it would go without saying that mineral supplementation would be beneficial to wild, free-ranging deer.
MINERALS AND THEIR FUNCTIONS
Minerals are defined as inorganic crystalline chemical elements and originate in the soil. The
specific mineral content of the soil is dependent on several factors such as the type of rock formations found in the area, the age of the soil, agricultural practices, erosion, etc. Vegetation pulls mineral for the soil as various minerals are needed for plant growth and reproduction. Minerals are replenished through degradation of organic materials, manual fertilization, water runoff and a host of other methods. Animals get mineral from consuming vegetation, consuming other animals or getting it directly from the soil.
Minerals are categorized into two specific groups, macro minerals and trace minerals. Macro minerals are those needed in large quantities to maintain body health and productivity. Examples of these minerals are calcium, phosphorus, magnesium, potassium, sodium and chloride. Calcium is involved in bone and teeth formation, milk production, muscle contraction and nerve function. Phosphorus is also involved in bone and teeth formation and is important in acid-base balance. Magnesium is likewise vital for proper bone formation is also an enzyme activator in the glycolytic system. Potassium is involved in maintaining intracellular osmotic pressure, acid-base balance and muscle activity.
Sodium and Chloride are both involved in osmotic pressure and acid-base balance. Trace minerals are needed in smaller quantities but are nonetheless vital for normal body health and function. Trace mineral examples include zinc, iron, copper, manganese, selenium, iodine and cobalt. Zinc, copper and manganese are all involved in enzyme activity and are all vital for bone growth and development. Iron is involved in hemoglobin production and cobalt is needed for vitamin B12 production. Iodine is involved in thyroxine formation and selenium is critical for vitamin E absorption and retention and thus affects reproductive efficiency. These are only just a few of the examples of the functions of macro and trace minerals. Digestion of minerals mostly occurs in the small intestine either thru active absorption or by diffusion.
MINERAL FUNCTION IN DEER
When we were going through the laundry list of functions for minerals, you probably noticed that we mentioned bone growth and development several times. Calcium, phosphorus, magnesium, manganese and copper all play a major role in the production of bone. Because antlers are basically bone outside the body and a velvet antler is growing bone, it would stand to reason that minerals play a major role in antler growth. If you were to analyze a hardened antler, you would find that it contains slightly more than 50 percent mineral. Of that, calcium, phosphorus and magnesium make up the largest percentage at 22 percent, 11 percent and 3 percent, respectively.
Velvet antlers are composed of a protein substance called collagen that produces an internal infrastructure or matrix like that of the frame of a house. Over time, mineral is deposited on the protein matrix giving the antler its hardened structure. The more mineral deposited on the antler, the more dense the antler becomes and typically the more mass the antler exhibits. If you were to cut through a hardened antler you would notice that that it contains two distinct parts, a core with layers surrounding the core. The core appears porous compared to the solid layers surrounding it. The internal core is the protein matrix and the outside layers are mineral deposits. The more mineral deposited on the antlers, the thicker the outside layers will be. Contrary to what one might think, mineral is not taken from the diet and directly deposited on the growing antler. Instead, digested mineral is deposited on the deer’s skeletal structure and then absorbed from the skeleton and transported via the blood stream to the antler.
Another key role that minerals play is enzyme activity. Calcium, phosphorus, potassium, magnesium, iron, copper, manganese and zinc are all either activators or components of enzyme systems. Specifically, phosphorus and zinc are involved in protein synthesis. The significance of this is that proper mineral nutrition is needed for efficient digestion and utilization of other nutrients, which in turn effects growth and production.
One of the most common results of a mineral supplementation program is increased body weights which is in part, a function of efficient enzyme activity. Certain trace minerals such as copper and zinc are also involved in immune response. Supplementation of these two trace minerals have shown that animals react to and more effectively deal with immune challenges compared to animals that do not receive supplemental levels of these two elements.
Finally, proper mineral nutrition is needed for maximum milk production by a lactating doe and is crucial for the growth and development of the skeletal system of young deer.
THE ARGUMENT FOR SUPPLEMENTATION
I think that everyone would agree that the proper mineral nutrition is needed for growth, maintenance and overall health. However, some may question the need for mineral supplementation or that improvements in the deer herd will be seen if a supplementation program is put in place. Those opposed to mineral supplementation may argue that deer get all the minerals they need from the plants and forages they consume in order to survive. I would agree that deer may get all the minerals they need to survive, but the goal of most hunters and managers is to try and achieve maximum growth and health of a deer herd, which requires maximum nutrition to accomplish.
As we stated earlier, mineral comes from the soil and is utilized by plants for growth. Unless there is an over-abundance of minerals in the soil or mineral is replenished through fertilization, natural mineral replenishment will not keep pace with what is extracted from the soil. This is especially the case in mismanaged agricultural practice. For example, a field is farmed for years then let go fallow and in most cases is not fertilized to replenish the minerals taken out during the production years. This relationship between mineral availability in the soil and the resulting mineral content in plant material can easily be seen when comparing soil ages.The older the soil, the more mineral-deficient it will be.
The Midwest is one of the most agriculturally productive areas in the country and the soil found there is some of the youngest soil in the country as it consists largely of glacial till. Furthermore, river bottoms and creek bottoms will also exhibit higher productivity and higher mineral content from mineral deposits left during flooding that was eroded somewhere upstream. Even if your property is in the Midwest, it is likely low in one or more minerals.
Minerals have complex interactions and a deficiency in just one mineral can cause complications in several internal systems. Based on these factors, it is highly unlikely that deer on any given property receive all the minerals they need from the vegetation they consume to achieve maximum growth and production. Antlers are secondary sex characteristics, which means that a buck will not sacrifice health in order to grow bigger or more massive antlers. Because the minerals that are deposited on antlers come from the skeletal system, a buck will not absorb mineral from its skeleton at levels that cannot be replenished through the diet, thus sacrificing antler growth. Therefore, the only way maximum antler growth can be achieved is if maximum mineral is available in the buck’s diet. The same can be said for does and milk production.
We mentioned earlier in the article that mineral research on wild, whitetail deer is difficult at best. However, over the years, observed results from the practice of mineral supplementation have shown dramatic results. Deer herds fed mineral supplements will nearly always show increased body weights across all segments of the deer herd. This should not be surprising as this same effect has been seen for many years in domestic ruminants. Also, stronger healthier fawns and yearlings have been observed, which is likely a result of improved doe lactation.
Effects on antler growth normally are observed in two areas, mass and antler integrity. When a mineral supplement program is put in place, a noticeable increase in antler mass is observed. Increased antler density is also seen with a dramatic decrease in busted or broken antlers. Admittedly, there are a host of variables that can affect these production aspects, but these results have been seen in hundreds of deer herds across the country. Also, the results have been seen when mineral supplements are the only thing changed in a management program.
SUMMARY
If your goal is to achieve maximum health and productivity of your deer herd, maximum nutrition must be a part of your program. If you are lacking in any vital nutrient, your goal will not be achieved. Supplementation means to “add to” the existing diet, not to replace it. If you start taking a mineral supplement each day that does not mean that you quit eating. You are simply making sure that your body receives any minerals that may be missing in your diet. The same is true for mineral supplementation for deer. If mineral supplementation is legal in your area, I challenge you to try a mineral supplementation program for yourself. I would wager that the results you see will be all the proof you need for the effectiveness of mineral supplementation. Just make sure you are using a professional mineral product that is designed by experts and not a product that is really an attractant.
