Livestock nutritional needs are at their highest demand during the winter months. Unfortunately, during this season, forage quality is often at its lowest. Winter feed costs are the single largest expense in a cow/calf operation. The winter feeding program on your farm will all depend on the body condition of your cows, the quality of forage that is fed, availability of winter feed supplements and costs.
In Ohio, a large percent of winter feeding occurs 60 days before calving during which a majority of fetal growth occurs. Through 90 days after calving which includes lactation and rebreeding, both increase the nutritional needs of the cow. During this 150 day period the cow’s diet should be sufficient enough to maintain a body condition score (BCS) of 5 to 6. (Body Condition Scoring utilizes a 9 point scale to assist with determining the health of your cattle with 1 being emaciated and 9 is obese.) At the 5 to 6 BCS level, a cow should be able to maintain her body weight and support production functions such as fetal growth, calving, lactation and rebreeding.
Depending on the quality of the forage being fed, supplementing the cows may be necessary. When forage quality is low most times we are looking to either a protein or energy deficiency or sometimes both in our hay crops. That is why BCS and forage testing your hay crop is so important. The goal of supplementation is to provide nutrients to the cows that are not available in sufficient quantity or adequate balance and to do this economically.
Supplements are classified broadly as protein supplements or energy supplements. Both of which contain protein and energy. The difference between the two is the relative concentration of protein. Protein supplements contain high concentrations of protein, usually 25% crude protein or greater. Energy supplements contain lower concentrations of protein, generally less than 18% crude protein.
The protein level in the ruminant diet is crucial for microbial growth and function. Without protein supplementation, the rumen cannot adequately digest that poor quality hay. In a low protein diet, digestion is slow and cows can actually not get enough to eat and lose weight.
Cold temperatures significantly raise a cow’s energy requirements. Undeveloped winter hair coats, wet hides and wind all combined can cause an increase in energy requirements.
One of these protein feedstuffs such as soybean meal (48% CP) or cottonseed meal (44% CP) can be combined with corn (which is an energy source) in a ration that can be used as a feed to supplement low quality forage thereby increasing the nutritional value of your winter feeding program. If you don’t have the proper equipment or labor that it takes to feed a grain ration to meet your cow’s needs then you may want to look at using protein tubs as a supplement to your winter forage. These tubs contain a mixture of protein sources, grains, vitamins, minerals and molasses that is cooked and hardened to form a sweet lick product containing 24 – 30% protein that cows can utilize for their nutritional needs with less labor from the producer.
The most accurate way to determine the protein or energy supplemental needs of your cows on a hay diet is to have your hay analyzed for nutrient content. This can cost from $15 to $30 per sample, but in the long run it can save your operation hundreds of dollars in winter feeding cost. For more information on how to acquire a forage nutrient test, see the short video by OSU Extension Educator Clif Little: