AUBURN, Ala. – It is important to understand the quality of energy and protein supplements fed to livestock.
“Energy and protein supplements are important because they allow a cattle producer to provide his or her cattle with adequate amounts of nutrients,” said Sarah Dickinson, Alabama Extension Animal Science and Forages Regional Extension Agent.
Energy is the available energy in a feedstuff as a percentage of the Total Digestible Nutrients, TDN, in the feed.
Energy supplements are feedstuffs that have a high percentage of TDN (greater than 60 percent TDN) that help meet a cow’s energy needs.
Corn and soyhull pellets are two common energy supplements that are high in TDN but do not provide a considerable amount of protein.
“These supplements would be best utilized when forage protein is adequate and energy is limited,” said Dickinson.
Protein supplements are feedstuffs that are high in crude protein, CP, and is used to help meet a cow’s protein needs or help increase the rate of fiber digestion in the cow or both. A feedstuff is considered a protein supplement if the CP is greater than or equal to 25 percent.
“Protein supplements can increase the rate that a low quality fiber is digested, and will thus allow your cows to eat more of that low quality forage than they would without the protein supplementation,” said Dickinson.
A protein supplement can increase an animal’s forage consumption if the forage CP is less than 7 percent.
Soybean meal, cottonseed meal, corn gluten feed and whole cottonseed are common protein supplements. These protein supplements are also high in energy and can be used as energy supplements.
Importance of Feedstuff Quality
“During times when pasture or stored forages do not meet animals’ nutrient requirements, energy and protein supplements can be provided to the herd to fill in the gap between the animals’ requirements and the level of nutrients in the forage,” said Dickinson.
It is important to make sure animals are provided supplements with the proper amount of TDN and CP to ensure they maintain a proper body condition score of 5 or higher.
Proper energy and protein supplements help keep cows in adequate condition to avoid pitfalls or production, such as slower re-breeding rate, lower overall pregnancy rate, more calving difficulty and lower weaning percentage of the calf crop with lower weaning weights.
What to Supplement
When determining what feedstuff is needed to supplement a herd’s diet, producers need to consider the herd’s stage of production, hay or forage quality and their ability to provide supplementation.
A hay test is an easy way to provide producers with the percentage of TDN and CP in their hay and from the results, they can determine the expected intake of their animals and the amount of TDN and CP the herd is expected to consume. Supplementation will be needed if the expected amount of TDN and CP in the hay is less than the animals’ energy and protein requirements.
“While many perennial grass hays will be deficient in both TDN and CP at certain stages of a cow’s productive cycle, producers should take note that TDN is usually the most limiting nutrient in our cow-calf production systems,” said Dickinson.
When to Supplement
Age of the herd, the stage of production the herd is in and forage quality affect the type of feedstuff supplementation required.
For example, young calves will have a higher protein requirement because they are still growing and need the protein to support their rapid growth.
As the herd mature the feedstuff requirements change as they move from calving, lactation, pregnancy and weaning.
“Cows have the highest nutrient requirement during the first three months after calving,” said Dickinson. “This first three month post-calving is a time when cows are in peak lactation, and are trying to re-breed.”
After the cows are re-bred the nutrient requirement will decrease until the calf is born and weaned. The cows’ nutrient requirements will continue to decrease and will remain low until just before she has her next calf.
“Having a defined calving season will allow a producer to better know the needs of his herd since all animals will be in the same stage of production and have similar nutrient needs,” said Dickinson.
Common Mistakes to Avoid
According to Dickinson there are three common mistakes producers make with feedstuff supplementation.
- Not properly comparing supplements for price: Always compare supplements for price in terms of “cost per pound of nutrient.” For example, if a supplement is 20 percent CP and costs $233 per ton or $233 per 2,000 pounds:
2,000 lbs. x 20% CP= 400 lb. CP
$233/ton ÷ 400 lb. CP= $0.58/ lb. CP
- Failing to test hay. Without a test to know the quality of the hay any supplementation decisions made will simply be a guess.
- Forgetting about the energy. Neglecting to factor in the TDN values in our supplement decisions may lead to animals that are not properly supplemented for energy. Check TDN values on feeds that you purchase and make sure they meet your cows’ energy needs as well as protein.
For more information on feedstuffs and feedstuffs quality contact your local Alabama Cooperative Extension Animal Science and Forages Regional Extension Agent.