March 30, 2009

BEEF CATTLE NUTRITION

MINERALS AND MINERAL PREMIXES

Mineral nutrition is one of the most important elements in the success (or failure) of today’s beef cattle producer.  It is also often one of the least understood components of the bovine diet.  Minerals play key roles in the reproductive efficiency, immune function, and weight gain in cattle. In other words minerals are essential in getting more cows bred, fighting disease and keeping cattle healthy, and increasing the growth rate of cattle. If you stop and think about where you would like your operation to be, this should coincide with most of your goals.

How do we determine our needs?  You could talk to a consultant working for a big mineral company. The down side of this is that there are often no education requirements for such a job, many are from out of the area, and many have probably never even owned a cow, and lastly most if not all are paid on some kind of commission so the important thing to them is that you buy something. You could go to a feed store. They will probable have one mineral mix sold to them by one of the big mineral company consultants.  Of course there are exceptions and some may have excellent advice.  Lastly, you could talk to an extension agent or veterinarian.  These are probably the best options but it is important that you find a person that has knowledge and interest in bovine nutrition and also experience. Then your veterinarian can talk to a nutritionist at the big mineral company and come up with an adequate formula at a fair price.  It is important to note that mineral needs vary from region to region and even from ranch to ranch within a region.

How does your veterinarian determine what you need?  Feed samples have been used by many people.  They are relatively easy because no cow is involved.  These are somewhat accurate on hay during the winter but when cattle are in a range situation or even a pasture situation with multiple plants, forage testing does not necessarily represent the true picture.  The first problem is that cattle are selective grazers and therefore may not consume the plants tested in the same percentages.  Plants have variable rates of mineral uptake.  The second problem is these tests are limited because it is difficult to predict absorption of the minerals due to all of the possible mineral interactions.  Therefore I always recommend testing the cattle.  This is done on blood samples for some minerals and on liver samples for others.  Liver biopsies are not as easy to do and more expensive. Often enough samples can be readily obtained from death losses and/or animals that are butchered.  You need to use caution when using samples from dead animals because many diseases, especially if they are prolonged, lead to changes in mineral levels and can therefore give you false information.

Selenium (Se) deficiency in severe cases leads to white muscle disease, diarrhea, and sudden death in calves.  Less severe signs include retained placentas, abortions, weak or stillborn calves, decreased fertility for several reasons, reduced growth rates, and reduced immune function.  Our area is very deficient in selenium and replacing this mineral alone can easily pay for the entire mineral program.  Injectable selenium products may help if you get behind on selenium but they only last for 2 or 3 months depending on the severity of the deficiency.  Feeding Se gives you a steady level instead of the highs and lows obtained with injectable products.  In addition, some injectable products such as Multi-Min do not contain vitamin E and are only effective for Se if a vitamin E injection is given at the same time.

Copper (Cu) deficiency causes poor or rough dull hair coats, reduced growth rates, diarrhea, sudden death in calves, reduced fertility in cows, reduced semen quality in bulls, retained placentas, improper bone development, foot rot, reduced immune function and more.  The severe copper deficiencies in our area are secondary to a high molybdenum concentration in our soils and therefore our forages, which interferes with Cu absorption.  In most cases we can maintain adequate Cu level by utilizing Cu sulfate in our mineral mixes, but in some cases this is not adequate and the addition of chelated Cu products is required.  If you have not checked the Cu status of your herd do not assume it is adequate just because you are on a mineral.

Zinc (Zn) deficiency leads to weak hooves creating susceptibility to foot rot, reduced conception rate, impaired sperm maturation, decreased feed intake leading to reduced growth rate, delayed wound healing, and reduced immune response.

Manganese (Mn) deficiency has been linked to reduced conception, abortions, and skeletal damage in newborn calves.

Magnesium (Mg) deficiency is well known for causing grass tetany in the spring of the year.  Also a sub-clinical deficiency can occur, causing reduced feed intake which ultimately results in decreased production.

Iodine (I) deficiency leads to reproductive failure, retained placentas, foot rot, and increased respiratory disease.  It is not known to be deficient in this area but it may help decrease the incidence of foot rot, lump jaw, and woody tongue when added to a mineral at therapeutic levels.

Phosphorus (P) deficiency causes reduced feed intake, decreased milk yield, unthriftyness, lethargy, decreased growth rate, impaired reproduction, bone abnormalities, and decreased immune function.  Phosphorus deficiencies are common in native pastures and harvested forages.  Phosphorus is the most expensive addition to a mineral mix and therefore should be used only when necessary to help keep your costs down.  The most critical time to maintain phosphorus is during the breeding season.  Cows that are still growing have higher requirements due to growth, and older cows beginning at 6 or 7 years of age have decreased absorption and therefore higher requirements also.

Calcium (Ca) is often seen on the label when Phosphorus is being supplemented.  Ca deficiency is not a problem under our normal feeding conditions.  The reason we see Ca on labels is that the most commonly used and commercially available Phosphorus source is dicalcium phosphate (dical).  It is also important to consider the Ca:P ratio which should remain between 1.5:1 and 5:1.  Remember you have to consider the ratio of the total diet and not just the ratio in the mineral supplement.  On high Ca feeds such as alfalfa additional P may be required to keep this ratio in the proper range.  Ca deficiency can be seen if cattle are on poor food sources after calving, when milk production is high.

Potassium (K) is the third most abundant mineral in beef cattle.  Under normal circumstances our diets are adequate in K and additional supplementation is not recommended.  K supplementation reduces Mg absorption thus making Mg deficiency more likely.

Salt, sodium and chloride (Na & Cl), is also required.  In certain areas this is supplied by alkaline water or plants, i.e. salt grass.  Inadequate salt intake can lead to decreased feed intake and all the problems that go with it.  Salt as will be discussed later is very important for helping us control consumption in mineral mixes. 

Cobalt (Co), Chromium (Cr), and Nickel (Ni) are also important for beef cattle but they are adequate in this area and additional supplementation for this area is not warranted with our current knowledge.  In other areas there may be a to add one or more of these to your minerals.

Consumption is key.  The most expensive mineral in the world is useless if cattle don’t eat it.  It is also important when comparing prices.  A $500/ton mineral fed at 2 oz/day is less expensive than a $300/ton mineral fed at 4 oz/day.  Most mineral mixes use salt to control consumption.  Beef cows will usually consume about 2 ounces of salt a day.  Mineral mixes containing mostly salt will be about the same.  Mg and P will decrease consumption as they are not very palatable, therefore as these are increased the amount of salt needs to be decreased to get adequate consumption of the mineral mix.  Also in alkaline soils containing plants such as salt grass or when cattle are drinking alkaline water they may not eat salt.  This does not mean they will not eat mineral.  In some of these situations as little as 4% salt causes cattle to not eat the mix.  In this case a 0% salt mix is used using grain (mill run, wheat fines, etc.) as the carrier.  It may take cattle a short time to adapt but they will all eat grain.  Then to decrease palatability and control consumption we add back unpalatable products such as Mg and P.  This increases the cost of the mineral significantly but it is still economical.  Mineral mixes may have to be individualized to your ranch to achieve proper consumption.  When asked about consumption most producers have no idea.  If you know how much you feed in a given amount of time, and how many cows you feed it to, then consumption can be calculated and adjusted if needed. 

Mineral mixes are difficult to press into blocks and it is less economical to design custom mixes with blocks.  Custom mixes and changes can be readily made with a loose mix, at least in ton quantities.  Blocks are also more expensive due to binders and the extra mill processing.  These mixes should be feed year round when feasible to ensure adequate mineral nutrition.  If this is not feasible during months when cattle are turned out, a trace mineral or selenium salt block is better than nothing.  Also building or investing in covered mineral feeders can help assure consumption during wet weather.  If you are in a wet environment then anti-cake products can also be added.

The cost of a good mineral mix will range from $400 to $700 per ton depending on the requirements for the time of year.  This equates to 2.4 to 4.5 cents per cow per day.  Calves will eat approximately half this amount just before weaning.  We can get by most of the time feeding the more expensive minerals for short periods when they are needed.  Expect to spend $13-$20 per pair per year for a good quality mineral program.  This includes the mineral for the calf prior to weaning.  If this sounds expensive re-read the portion on the problems caused by mineral deficiencies and figure out what they cost you.  A good mineral program will easily put 10 or 15 pounds more on your calves which pay for the mineral.  Increased conception rates, additional gains, and increase health in your herd are bonuses.

LakeviewAnimalHospital serves as a dealer for Inman & Co a division of Wilbur Ellis and Pine Creek Solutions, Inc.  Our status as a dealer allows us to by at wholesale prices and sell minerals for the same price as if you ordered direct.  You also have the same options for ranch delivery either way.  By ordering through Lakeview Animal Hospital you keep a small percentage of the money in town and get veterinary input on your mineral mix at no additional cost to you.  And of course you get the same quality assurance that you get with other products purchased from Lakeview Animal Hospital.  In 2005 numerous manufacturers’ samples in Oregon were tested by the Oregon Dept. of Ag. Feed Registration Division.  It was surprising to me to see how many samples were not within the specifications on the labels showing the importance of dealing with a trusted company.  It is common for mineral salesmen to try and sell you a different formula usually light on some of the needed ingredients in order to try and meet or beat someone else’s price.  The other approach is to convince you that you need to spend more because your mineral is not complete enough and then put in several minerals you don’t need.  Many only have one or two formulas for a region and this is not adequate, many of our ranches utilize 3 or 4 formulas for one ranch.  Special products for fly control, coccidiosis, growth promotants, anti-cake products, and antibiotics can also be added easily.  Keep these tips in mind when developing your mineral program.