Cornell University researchers found that replacing antibiotics with grape pomace in poultry nearly matches conventional antibiotic performance.
Every year, wineries around the world produce millions of tons of waste in the form of grape skins, seeds, and stems left behind after grapes are pressed for juice. Known as grape pomace, this material is often discarded, composted, or used for low-value products. Now, researchers have discovered a surprising new purpose for this winemaking byproduct: helping to reduce antibiotic use in chicken farming.
A new study from Cornell University suggests that replacing antibiotics with grape pomace in poultry may be a viable option for improving bird health while creating a more circular food system. The research found that adding small amounts of grape pomace to broiler chicken feed produced results that nearly matched those achieved with a commonly used antibiotic growth promoter.
The study focused on zinc bacitracin, an antibiotic frequently used in poultry production to improve growth and feed efficiency. While antibiotics can help farmers raise healthy birds, their widespread use has raised concerns about antimicrobial resistance. Health experts worldwide have warned that excessive antibiotic use in agriculture may contribute to the emergence of drug-resistant bacteria that can affect both animals and people.
Because of these concerns, researchers have been searching for natural alternatives that can support poultry health without relying on antibiotics. The Cornell team found a promising candidate in grape pomace, an abundant, inexpensive byproduct of the wine industry.
In controlled feeding trials, researchers added grape pomace to broiler chicken diets at levels as low as 0.5% of total feed. The results were striking. Birds receiving the supplement achieved growth performance and feed conversion rates that closely resembled those of chickens receiving zinc bacitracin. Feed conversion is an important measure in poultry production because it reflects how efficiently animals convert feed into body weight.
The findings suggest that replacing antibiotics with grape pomace in poultry could help farmers maintain productivity while reducing dependence on routine antibiotic use. According to the researchers, the benefits appear to come from naturally occurring compounds found within grape skins and seeds. These compounds include polyphenols and other bioactive substances known for their antioxidant and antimicrobial properties.
Scientists believe these compounds may help shape the microbial communities living in a chicken’s digestive system. A healthier gut microbiome can improve nutrient absorption, strengthen immune function, and support overall growth. Rather than killing bacteria as antibiotics do, grape pomace may help create conditions that favor beneficial microorganisms.
Replacing antibiotics with Grape pomace in poultry works by shaping microbial communities in chickens’ digestive systems, creating conditions that favor beneficial microorganisms that improve nutrient absorption, strengthen immune function, and support overall growth, rather than killing bacteria as conventional antibiotics do. Photo by Steven Van Elk on Unsplash.
The environmental implications are equally significant. Wineries generate vast quantities of grape pomace every year, and finding higher-value uses for this material remains a challenge. Converting agricultural waste into livestock feed represents an example of circular economy thinking, where one industry’s byproduct becomes another industry’s resource.
This approach could reduce waste while creating new revenue opportunities for vineyards and wineries. Instead of treating grape pomace as a disposal problem, producers could potentially supply it to livestock operations seeking sustainable feed ingredients. Such partnerships could strengthen connections between agricultural sectors while improving resource efficiency.
The concept aligns with a growing movement toward more sustainable animal agriculture. Researchers around the world are exploring alternatives to antibiotics, including probiotics, plant extracts, algae, and fermented feed ingredients. The success of using grape pomace to replace antibiotics in poultry adds another promising option to this expanding toolkit.
Challenges remain before widespread adoption becomes possible. Feed ingredients must be available in consistent quantities, and farmers need assurance that results can be replicated across different production systems. Additional studies will also be necessary to evaluate long-term impacts on bird health, food safety, and farm economics.
See also: Exploring the Role of Dried Mealworms in Sustainable Animal Diets
Even so, the early findings are encouraging. The study demonstrates that materials once considered waste may hold untapped value for addressing some of agriculture’s biggest challenges. By transforming leftovers from one industry into a resource for another, researchers are uncovering innovative ways to improve sustainability without sacrificing productivity.
As food systems seek solutions that balance environmental responsibility with economic realities, grape pomace as a replacement for antibiotics in poultry offers a compelling example of circular innovation. What begins as vineyard waste could ultimately support healthier chickens, reduce antibiotic use, and create a more sustainable future for farming.
