For most producers across the Plains, forage supplies are looking limited because of decreased forage production from persistent drought conditions, making now a suitable time to explore alternative feed options. Producers should begin evaluating current forage inventory to determine how much feed is needed to carry livestock through the rest of the season and begin making purchasing decisions in a timely manner before supplies dwindle further and prices increase. Agricultural byproducts such as distillers grains, soybean hulls, sunflower meal, and crop residues are a readily available and cost-effective solution to stretch hay supplies when resources are limited.
Many byproduct feeds provide a reliable source of high-quality digestible energy, protein, and/or fiber. Depending on local markets and resources, byproducts are often readily available in the Northern Plains and can be a cost-effective feedstuff for livestock producers. Byproducts are most effectively fed to livestock when used as part of a balanced ration rather than used as a complete replacement for forages. When used in conjunction with forage resources, byproducts can serve as a great option to conserve hay inventory, reduce feed costs, and improve operational flexibility during dry years.
Common agricultural byproducts available in South Dakota include distillers grains, soybean hulls, wheat middlings, beet pulp, corn gluten feed, and sunflower meal. Soy hulls provide moderate energy and are high in digestible fiber, making them a great resource to replace a portion of hay in the diet. Wheat middlings are an all-around byproduct that provides moderate sources of protein, energy, and fiber to livestock making them a great feed source for most species and classes of livestock. Beet pulp provides a highly digestible source of fiber and moderate source of energy, which helps maintain rumen environment and offset nutrient deficiencies found in lower-quality hay and crop residues. Corn gluten feed supplies adequate sources of protein, energy, and digestible fiber and is an economical supplement option that can replace a portion of hay in the diet. Sunflower meal is high in protein and provides some additional fiber, making it a great protein supplement when livestock are consuming low-quality forages or crop residues.
When determining what byproducts to feed livestock, it is important to utilize forage and feed tests to know exactly what nutrients are being provided and which may require additional supplementation. Using that information to determine which feedstuffs are most cost-effective based on price per nutrient rather than price per ton is essential to reducing supplementation costs. Table 1 demonstrates an example of comparing different feedstuffs based on cost per pound of protein rather than cost per ton. To determine cost per pound of nutrient producers should first determine cost per pound of feed.
Feed cost per ton / 2,000 = $/lb of feed
After determining price per pound of feed, determine the pounds of nutrient per pound of feed.
Feed crude protein % / 100 = lb of nutrient per lb of feed
Once pound of nutrient per pound of feed has been calculated, calculate cost per pound of nutrient.
Cost per lb of feed / lb of nutrient per lb of feed = cost per lb of nutrient
Additional cost and labor considerations associated with transportation, storage, mineral balance, and availability should also be factored in to help make purchasing decisions.
| Feed | Cost per Ton($)1 | Crude Protein (%)1 | Cost per lb of CP ($) |
|---|---|---|---|
| Soybean Hulls | 250 | 12 | 1.04 |
| Distillers Grains | 300 | 30 | 0.50 |
| Wheat Middlings | 240 | 18 | 0.67 |
1Cost per ton and protein content of feedstuffs are examples only and do not represent market or specific nutrient value. When purchasing byproducts, producers should request a nutrient analysis to help make purchasing decisions.
Crop residues serve as another useful and readily available resource to help stretch tight hay supplies. Corn stalks, small grain stubble, and sorghum and soybean residue can provide additional grazing opportunities to extend grazing days and conserve hay supplies. It is important to recognize that using crop residues is most cost-effective and nutrient dense immediately following harvest as selective grazing will decrease nutrient-dense grain, leaves, and husks over time. Because of this decrease in nutritive value over time, some additional supplementation is often necessary when grazing crop residues. Often, when grazing crop residues, protein is the first limiting factor. A general rule of thumb to follow when grazing corn residue, is when there are no longer any kernels in the feces it is time to move livestock or provide additional protein supplementation. Agricultural byproducts can serve as a readily available supplementation resource that compliments crop residue grazing. Stocking rate and grazing length is highly variable and dependent on the amount of grain remaining following harvest. When grazing sorghum residue, special consideration should be given to the possibility of excessive nitrate accumulation following drought years or on heavily fertilized fields. Use forage and nitrate testing to understand risks and determine how to safely feed livestock high-nitrate feedstuffs.
Crop residues and byproducts can be valuable tools to help stretch forage supplies when resources are limited. Taking inventories and evaluating feed needs and resources in the late summer can improve flexibility and help producers enter the winter months with greater confidence. Understanding the nutritional needs of livestock and how to best match nutrient content of feeds to those needs will maximize feed efficiency and reduce feeding costs. For more information on matching feed supply with livestock nutrient needs, see Matching Winter Forage Supply to Herd Needs.
