All cattle require nutrients including protein, energy minerals & vitamins for optimum maintenance, growth and reproduction. Developing a successful winter cow feeding program involves several important steps.
Step 1. Determine the cow’s nutrient requirements and how they are influenced by age, size, breed, and body condition. The cow’s reproductive status, or stage of pregnancy has the greatest influence on a cow’s daily nutrient requirements. The mature beef cow’s yearly nutrient requirements can be divided into four separate nutritional periods, each one defined by the cow’s reproductive status. These periods include calving through breeding, breeding through weaning, weaning to 60-90 days prior to calving and 60-90 days prior to calving to calving. Table 1. lists the daily nutrient requirements for a 1200-pound beef cow for each of these four production periods.
From Calving through the end of the Breeding Season
The nutritional needs of the beef cow are highest during this period, she is producing milk to support a rapidly growing calf and preparing for breeding. A supplemental source of protein, energy, minerals and vitamins is often needed.
From the end of the Breeding Season through Weaning
By this time, the cows are bred, they are near peak milk production, and the calves are utilizing mostly forage to supply their nutrient needs. Spring-calving cows are normally on pasture by this time and if pastures are in good condition, little or no protein or energy supplementation is required. Only minerals are needed. This is a very challenging time the fall-calving cow herd. The cows are bred, still producing milk and the calves are growing rapidly. It is usually also mid-winter so cows are either grazing winter range or fed hay. Fall calving cows need both protein and energy in order to maintain milk production and body condition.
From Weaning to 60 days prior to Calving
The cow’s daily nutrient requirements during this period are the lowest they will be all year. Her calf has been weaned and she is in the early stages of pregnancy. The amount of energy, protein and mineral supplementation required is determined by the quality and quantity of forage available, and the body condition of the cow. Since the cow’s maintenance requirements are low, this is an excellent time to add body condition to an otherwise under-conditioned cow.
60 Days prior to Calving to the start of Calving Season
During this period the cow’s nutrient requirements increase significantly due to the rapid growth of the fetus. Additional protein, energy and mineral supplementation are normally required. The amount will depend on the quality of the forage available and the body condition of the cows. Numerous university research studies have demonstrated the importance of good nutrition during the last trimester of pregnancy. Supplementing beef cows with protein has been shown to improve body condition scores and improve reproductive performance. In addition, calves from protein supplemented cows were heavier at weaning and maintained that weight advantage throughout their life. Mineral nutrition is also important during this period. Cows fed supplemental trace minerals during the last trimester of pregnancy weaned calves that were 25-50 pounds heavier than calves from unsupplemented cows. Those calves also maintained that weight gain advantage throughout the growing and finishing phase. Dr. Rick Funston of the University of Nebraska uses the term “Fetal Programming” to describe the concept that the nutrient status of gestating cows may have various far reaching implications on their offspring, even before they are born.
Step 2. Determine what forages are available, how much you have and the nutritional composition of each available forage. Any winter cow feeding program should start with the forage. Forage is the most readily available and most economical source of nutrients for most beef cattle producers. Winter cow feeding programs may consist of dormant pasture, winter range, winter annual or over-seeded pasture, hay or even silage. The typical or average nutrient composition of various forages can be found in numerous publications from the National Research Council and your State Cooperative Extension Service. Forages can differ widely in nutrient content and can vary from season to season and year to year. A laboratory forage nutrient analysis is recommended for each forage in order to determine the actual nutrient content of a particular forage. Western Feed Mills can assist you with sampling your forages and submitting them to the lab.
Step 3. The next step is to determine how much of each nutrient is supplied by the forage. Most cattle producers know how much hay they feed to their cows on a daily basis, however, it is more difficult to determine forage intake when cattle are grazing dormant pastures or winter range. Gestating beef cows grazing dormant grass pasture or winter range, or fed prairie hay, straw or other low-quality forages will consume about 1.8% of their body weight in forage dry matter daily. For example, a 1200-pound gestating beef cow on dormant winter range will consume approximately 21.6 pounds of forage dry matter. The intake of higher quality forages can be as high as 2.2 to 2.5% of body weight. Feed intake will also increase as cows get closer to calving and after they calve. To determine the amount of each nutrient provided by the forage you multiply the number of pounds of each forage fed daily by the percentage of each nutrient in the forage. For example, a 1200-pound gestating beef cow consuming approximately 21.6 pounds of winter range that is 4.65% crude protein will consume 1.0 pound of crude protein This sounds simple, but it can be complicated due to the number of nutrients and the number of forages fed. Western Feed Mills can assist you in determining how much of each required nutrient your forage provides.
Step 4. Once you have determined the amount of each nutrient the cow needs (from the table above) and the amount of each nutrient supplied by the forage, the next thing to do is compare those two values to determine how much of each nutrient must be supplied by a supplemental feed. This is often called the “Nutritional Gap” or the amount of a nutrient the cow needs that is not supplied by the forage. Table 2. shows the daily amount of crude protein and energy (TDN) required by a 1200-pound cow during the last trimester of pregnancy, along with the amount of crude protein and energy supplied by a typical daily intake of winter range. Without additional supplementation, the cows in this example would be deficient in both protein and energy.
One way to provide the supplemental crude protein and energy that cows need during the winter months is to feed a Western Feed Mills range feed. There are several products to choose from with protein levels ranging from 14% to 38%. Selecting the supplemental feed that compliments your available forage and meets your cow’s nutritional needs is important. Underfeeding may cause performance loss while overfeeding is wasteful and costly. Table 2. shows the daily feeding rate needed to supply the required amount of supplemental protein for three feeds with different protein levels. The amount of supplemental TDN is also shown. Feeding the prescribed amount of either a 20% or 30% protein feed will supply both the protein and energy needed by the cow during the last trimester of pregnancy. Feeding a 38% protein feed will supply the needed protein but will not supply the necessary energy.
Western Feed Mills or your Western Feed Mills Representative can help you select the supplemental feed that is right for your operation. Remember that a nutritionally sound winter cow feeding program can result in cows that are in good body condition, raise a bigger, healthier calf and rebreed on time. These are all performance criteria that define an efficient, profitable beef cow operation.