Diet Reformulation Strategies: Adding Byproducts
alternative practice names:
BiProducts; Use of Food Wastes; Feed Commodities
Byproduct feeds are residues generated from processing agricultural raw materials. For example, humans consume canola and soybean oil, but the residual canola and soybean meals (80% of the beans) are typically used as primary protein sources in dairy diets. Similarly, about half of the corn grain processed for human food or ethanol remains as byproduct feed. Byproduct feeds commonly fed to dairy cows include almond hulls, soybean meal, canola meal, corn distillers’ grains, corn gluten feed, corn gluten meal, wheat byproducts, bakery products, cottonseed, brewers’ grains, chocolate, blood meal, citrus pulp, beet pulp, molasses, and whey. Byproducts do not replace the need for high-quality forages, and "high" byproduct rations are typically less than 50% byproduct.
Dairy cows can upcycle nutrients from byproduct feeds into nutritious milk and dairy products. Most U.S. dairies feed some byproduct feeds to their cows. However, increasing byproduct feed inclusion in dairy cow diets can reduce feed costs and provide an opportunity to reduce the environmental impact of dairy production.
When used, in what regions in the U.S. is the practice found:
Northwest, West, Upper Midwest, Southwest, Northeast, Southeast
FARM SIZE
When used, typically found on farms of the following sizes:
All Sizes

Practice Benefits
Increased profitability: Using advanced nutrition models combined with laboratory evaluation of feeds, dairy nutritionists develop diets using a combination of forages, whole grains, byproduct feeds, and feed supplements. The goal is to meet the cow’s nutrient requirements with the least expensive combination of forages and feeds. Since byproduct feeds are generally less expensive than whole grains, feeding byproducts often reduces diet costs while maintaining milk production to increase profitability.
Increased milk production: Byproduct feeds can deliver compounds or nutrients that are otherwise difficult to provide, such as protein and dietary sugars. Some byproduct feeds supply readily digestible fiber, which, if used to replace a portion of the dietary starch, can provide needed energy while improving rumen health as well as milk and milk component production. Certain high-fiber byproduct feeds have intermediate fermentability relative to forage and concentrate feeds, supplying readily digestible fiber with the potential to improve milk and component production. Incorporating these byproducts into the diet can help maintain or even enhance milk yield and quality, thereby boosting production efficiency.

Implementation Insights
Site-specific or Farm-specific requirements

Geography: Geographical location will determine the availability and price of many byproduct feeds. For example, dairies in the Southeast have greater availability of low-priced citrus byproducts, while California dairies typically have an economical supply of almond hulls. Many byproducts are seasonally available, and therefore, the ration will need to be reformulated as specific byproducts come and go from the supply.
Required Capital Expenditures (CapEx)

Byproduct storage facilities: Farmers using various byproducts need storage facilities tailored to each type. The ideal storage method varies depending on each feed type's specific characteristics and requirements. Dairies equipped with flat storage, where feeds can quickly be delivered by dump trailer or auger, can handle many types of dry byproduct feeds. Preferably, storage structures should be covered to maintain feed quality and reduce waste. High-moisture byproduct feeds, such as wet brewers’ grains, require storage facilities capable of dealing with seepage. Liquid byproduct feeds, such as whey and molasses, require storage tanks equipped with pumps and possibly agitators. Many dairies, especially those that are larger, purchase and feed byproduct feeds as individual commodities. Feed mills often include byproduct feeds within grain mixes to be purchased by any farm regardless of size.
Total Mixed Ration (TMR) mixing equipment: While some byproduct feeds can be fed separately from forages and grains, it is generally preferred to include them within a TMR, which requires the purchase and maintenance of mixing equipment with scales.
Required Operational Expenditures (OpEx)

Byproduct feed: Byproduct feed costs are often comparable to or lower than alternatives with similar nutrient composition.
Implementation Considerations

Ration formulation: Byproducts can vary in nutritional content, requiring precise formulation and regular monitoring. Byproducts' costs and availability will vary depending on the region and time of year. Farmers incorporating byproducts into their rations must work closely with their dairy nutritionists to account for these variations.
Financial Considerations and Revenue Streams
There are no federal cost-share programs or conservation funding for this practice.
PROFIT POTENTIAL
The use of byproduct feeds should reduce diet costs to improve profitability.
Additional Resources
Article: Considerations for Using By-Product Feeds (University of Georgia)
Article: Cows Are The Unlikely Heroes In The Fight Against Food Waste (Time Magazine)
Article: Dairy Cows - The Original Upcyclers (UC Davis, CLEAR Center)
Report: By-Product Feedstuffs in Dairy Cattle Diets in the Upper Midwest (University of Wisconsin)

Environmental Impacts
UPCYCLES NUTRIENTS
Feeding byproducts to dairy cows aligns with sustainable resource management, where waste streams are considered resources to be used according to a hierarchy of options that deliver the best possible environmental and socioeconomic outcomes. Feeding byproducts from food processing waste streams to animals is the best option for unavoidable food waste and the second-best option after prevention for avoidable food waste.
MAY REDUCE FARM GREENHOUSE GAS EMISSIONS
While feeding byproduct feeds contribute to enteric and manure non-carbon dioxide greenhouse gas (GHG) emissions like all other feeds, feeding byproducts to dairy cows will result in considerably less non-carbon dioxide GHG emissions than landfill disposal (49-fold) and composting (4.7-fold) (de Ondarza & Tricarico, 2021). The U.S. Environmental Protection Agency considers recycling food surplus and byproducts into animal feed as a preferred choice over composting, burning, and landfilling.
INCREASES LAND USE EFFICIENCY
By replacing conventional feed ingredients like grains and forages with byproducts, dairy farms can reduce the demand for crops grown specifically for animal feed. Reducing the demand for grain reduces environmental impacts associated with grain production and increases land use efficiency.
See research highlights below:
Byproducts such as distiller grains and whole cottonseed have high protein contents, which can elevate the dietary N concentration when included in cattle rations. This increase in dietary N can lead to higher nitrogen intake, subsequently raising the potential for increased urinary N excretion. The elevated N excretion enhances the risk of NH₃ and N₂O emissions from stored manure and manure-amended soils, contributing to increased GHG emissions. See Diet Reformulation Strategies: Protein Balancing.
REFerences

Alignment with FARM Program
FARM Environmental Stewardship (ES) V2-V3 Alignment
FARM ES uses information about rations to calculate greenhouse gas emissions intensity, including enteric methane. The platform focuses on the lactating herd ration, with the option to enter details on rations for other animal classes. FARM ES Version 3 has the ability to run custom 'what-if' scenarios where users can change various inputs, including ration information, to determine the impact on farm emissions.
Contents
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
Byproduct feeds are residues generated from processing agricultural raw materials. For example, humans consume canola and soybean oil, but the residual canola and soybean meals (80% of the beans) are typically used as primary protein sources in dairy diets. Similarly, about half of the corn grain processed for human food or ethanol remains as byproduct feed. Byproduct feeds commonly fed to dairy cows include almond hulls, soybean meal, canola meal, corn distillers’ grains, corn gluten feed, corn gluten meal, wheat byproducts, bakery products, cottonseed, brewers’ grains, chocolate, blood meal, citrus pulp, beet pulp, molasses, and whey. Byproducts do not replace the need for high-quality forages, and "high" byproduct rations are typically less than 50% byproduct.
Dairy cows can upcycle nutrients from byproduct feeds into nutritious milk and dairy products. Most U.S. dairies feed some byproduct feeds to their cows. However, increasing byproduct feed inclusion in dairy cow diets can reduce feed costs and provide an opportunity to reduce the environmental impact of dairy production.
Practices and technologies
Diet Reformulation Strategies: Adding Byproducts
alternative practice name:
BiProducts; Use of Food Wastes; Feed Commodities