Now is the time to start planning your winter-feeding program. Adequate nutrition is vital for both the calf and cow in terms of health and productivity. Thin cows are harder to breed back; produce less milk and wean lighter calves. However, on the flip side, it is important to supplement only what is necessary without wasting feed or money in order to remain profitable.

General Cattle Nutrition

In order to make informed decisions regarding supplements, it is necessary to understand the basics of cattle nutrition. Cattle require proper amounts of energy, protein, minerals, vitamins and water in order to thrive and achieve maximum production and efficiency.

Energy is the first limiting nutrient in a cow’s diet and represents a major portion of a cow’s needs. Energy is the “fuel” that allows a cow to function. Energy needs are typically expressed in terms of total digestible nutrients (TDN). Most of the energy needs of cattle are met through the fermentation of forages and roughages in the rumen. Other energy sources include carbohydrates (primarily supplied by grains), sugars (from sources such as molasses) and fats.

Protein is composed of amino acids, which the body uses as “building blocks” for body tissues. In ruminants, the bacteria and protozoa in the rumen actually digest forage protein and convert it into microbial protein. These microorganisms are capable of converting non-protein sources of nitrogen (NPN) such as urea, into the same microbial protein under normal conditions. Since the cow cannot differentiate between the microbial protein produced from natural forages and that produced from NPN, urea is often added as a way of economically increasing effective protein levels in supplements.

Minerals and vitamins are also essential to proper nutrition. Since mineral and vitamins levels vary in forages and feeds, always provide free choice access to a complete mineral and vitamin supplement containing salt to avoid deficiencies in your cattle. Avoid use of plain white salt blocks or trace mineralized salt blocks.

Water is often overlooked as a nutrient but is vitally important for cattle nutrition. Clean water is most important to young, growing calves. Inadequate water consumption will limit feed intake and reduce growth and performance.

How Do I Know if I Need a Supplement?

During winter months, most cattle producers rely primarily on hay as their main feed source. Good to high quality hay is an excellent feed source for cattle. However, hay quality varies greatly from year to year or even cutting to cutting. Environmental factors adversely affects hay quality, as well as man-made factors like improper fertilization and harvesting.

Because hay represents such a large portion of a cow’s diet and quality varies so much, it is strongly recommended that you chemically analyze your hay source(s) for nutritional content. This service is modestly priced and will save you money in the long run. By testing your hay, you will know its exact nutritional content and will allow you to make better management decisions. Knowing the nutritional content of your hay will allow you to more efficiently allot hay according to cattle needs. Knowledge of forage nutritional content will also allow you to save money by purchasing the correct supplements to meet the needs of your cattle – no more, no less.

This spring and summer’s hot dry weather has been hard on pastures. If you were fortunate to get enough rain that you could turn your cattle out on pasture, the grass is now dry and mature. There are several things that can be done to help under current drought conditions.  One of the first but not always the easiest is to wean the calves earlier than normal.

1.     The available grass is not adequate to meet the protein and energy requirements of the calf.

2.     The calves’ needs could be better met with a bunk ration.

3.     The cow will not be eating to produce milk.

4.     The calf will not be eating grass that could be feeding the cow.

5.     The calf is getting older but not gaining when grass is this short.

The requirements for a dry cow are considerably lower in both energy and protein than for a lactating cow. Weaning the calf will allow us to retain as much body condition as possible until we get the fall rains. It is expensive to put body condition back on a cow once she has lost it. It is cheaper to do what we can to keep condition on the cow.

What can we do to help the cow get more out of the grass left in the pastures? The dry mature grass will be lower in TDN and can be limited in protein content. Feeding limited amounts of corn, hay or grain by-products are some of the ways to get more energy and some protein into the cattle. Delivery costs, in addition to the cost of the extra feed, may be higher than necessary. And it may actually be negative to the digestibility of the remaining grass. 

Providing a self-fed limited amount of protein and energy will improve the digestibility of the grass and get more energy into the cow. A Crystalyx^® protein tub can deliver a controlled amount of self-fed supplement at an economical cost.  The following study at Kansas State University showed improved digestibility when a Crystalyx^® supplement was compared to a limited amount of corn. The amount of corn fed provided the same amount of protein as the Crystalyx^® supplement.  Neutral Detergent Fiber (NDF) is a measurement of the grass fiber digested by the beef animal.

The depression of NDF digestibility by the starch in the corn shows a very negative effect on digestion. Even when the amount of grass is not limited, the last thing we want to do is lower digestibility. The rumen microorganisms that use starch grow much more rapidly than the microorganisms that digest fiber. And the byproducts of their growth depress the growth of the fiber microorganisms. When just a little too much corn (or other starch) is fed, then the fiber digesting microorganisms (rumen bugs) cannot grow fast enough to digest the fiber before it leaves the rumen.

Fiber bugs have energy and protein requirements for growth which are easily met when grass is green and growing. It is a different story when grass matures. Mature dry grass is lower in readily available energy and protein making it more difficult to digest. Crystalyx^® protein tubs provide readily available energy and protein in small amounts allowing the bugs to use them to effectively digest fiber. Small multiple Crystalyx^® meals allow the bugs to use the nutrients instead of having the rumen overwhelmed by a single big meal (range cubes or grain byproducts). The easily available small amount of rumen degradable protein (RDP) provided by urea can be easily used by the bugs as a protein source. If there is no RDP then the bugs have to break down the grass protein or supplemental natural protein to use as a protein source for their growth. The same situation exists for energy. The molasses in the Crystalyx^® protein tub provides small amounts of easily digested energy used by the bugs to help digest the grass fiber. A University of Nebraska trial demonstrates using a combination of RDP and natural protein to supplement mature grass. They compared no supplement (Control) to an energy (ENG) supplement to a RDP (very soluble protein) supplement to a combination RDP/natural protein (RDP/EP) supplement.  The cows were nursing summer calves when these measurements were taken in late September.

The cows receiving the combination of protein sources gave the most milk and did not lose weight. Their calves and the calves from the cows receiving RDP gained the most weight. If the calves had been weaned then the energy and protein used for milk production would instead be used to maintain or improve body condition.

1. Forages may be deficient in nutrients that can limit animal performance whether it be cow reproductive efficiencies, calf health, and growth or stocker gains.

2. Stocker cattle and replacement heifers can easily gain up to 10% more on grass if provided a feed additive such as Rumensin^®, Bovatec^® or GainPro^®. There are a number of free-choice delivery methods available that have FDA approval for use in stocker cattle and replacement heifers.

3. A variety of free-choice supplements provide EPA approved delivery of feed-through fly control larvacides or insect growth regulators that can help reduce losses in particular with the presence of horn flies. Some compounds have additional fly specie approval including, stable flies, house flies and face flies.

4. Recent cattle market prices in combination with high grain prices have increased the urgency to get as much gain on forage-based programs as possible prior to cattle arriving in the feed yard. Supplements can greatly assist stocker operators in achieving aggressive weight gain to optimize pasture resources.

5. Free-choice supplement may be strategically located in pastures to help improve forage utilization by getting the most out of your land and forage resources.

6. Early in the growing season, Grass Tetany conditions can result in sudden death losses in mature lactating beef cows. Providing consistent delivery of a readily available Magnesium supplement can help prevent losses from Grass Tetany.

7. Drought conditions, late in the growing season and especially with stockpiled winter pasture, protein content of the forages will most often drop below animal requirements and performance will be reduced. Small additions of protein supplement will improve forage digestibility and prevent animal performance losses.

8. Mineral and vitamin supplementation on pasture is critical for maximizing animal performance and providing nutrients required for maintaining animal health.

9. Organic or chelated forms of trace minerals can be beneficial where there are extreme deficiencies or levels of antagonizing minerals that interfere with the use of trace minerals required for optimum animal performance. Organic  forms of Copper and Zinc in a mineral supplement will help overcome mineral antagonists that can be present in certain regions of the country or water sources.

10. High-producing purebred herds will require additional supplemental inputs to ensure that they perform to their genetic potential and maximize reproductive efficiencies.  Herds with greater than commercial market value are much more of an investment to protect and ensure that they have every opportunity to pass on their traits whenever possible.