According to Gram Research analysis, grape pomace—a byproduct from winemaking—can reduce intestinal inflammation in chickens and support growth as effectively as antibiotics, according to a 2026 study of 126 broiler chickens. The grape waste works by boosting beneficial gut bacteria and increasing production of butyrate, a compound that calms inflammation. Adding just 0.5% grape pomace to chicken feed produced results comparable to antibiotic treatment, offering poultry farmers a natural alternative as they move away from antibiotics.
A new study shows that grape pomace—the leftover skins and seeds from winemaking—might help chickens stay healthy without antibiotics. Researchers fed 126 broiler chickens different diets and found that those eating grape pomace had less intestinal inflammation and grew better than chickens on a challenging diet. The grape waste worked by changing the bacteria in the chickens’ guts and boosting helpful compounds called short-chain fatty acids. This discovery could help the poultry industry move away from antibiotics while keeping birds healthy and productive.
Key Statistics
A 2026 study of 126 broiler chickens found that adding 0.5% grape pomace to feed reduced intestinal inflammation markers (TNF-α and IL-1β) and improved growth rates to levels comparable with antibiotic treatment.
Research published in NPJ Biofilms and Microbiomes showed that grape pomace increased beneficial Lactobacillaceae bacteria in chicken guts and boosted butyrate production, a short-chain fatty acid that reduces inflammation.
In a controlled study of 126 chickens, fermented grape pomace (treated with beneficial bacteria or yeast) performed slightly better than non-fermented grape pomace at reducing inflammation and improving growth.
Gram Research analysis of this 2026 poultry study identified a specific pathway where increased Lactobacillaceae bacteria led to higher butyrate levels, which reduced inflammatory proteins and improved bird growth.
The Quick Take
- What they studied: Whether grape pomace (a byproduct from winemaking) could replace antibiotics as a growth promoter and health booster in chickens
- Who participated: 126 broiler chickens divided into six groups eating different diets, including standard feed, challenging high-fiber feed, and feed with grape pomace or fermented grape pomace
- Key finding: Chickens eating grape pomace had significantly less intestinal inflammation and grew better than chickens on a challenging diet without grape pomace, performing similarly to chickens given antibiotics
- What it means for you: If these results hold up in larger studies, chicken farmers could use grape waste instead of antibiotics, potentially leading to healthier poultry and safer food. However, this was a small study in controlled conditions, so more research is needed before widespread use
The Research Details
Researchers divided 126 young broiler chickens into six groups and fed them different diets for several weeks. One group got standard chicken feed, another got a challenging diet high in fiber (non-starch polysaccharides), and the remaining four groups got the challenging diet plus different additives: antibiotics, grape pomace, or grape pomace that had been fermented with beneficial bacteria or yeast. The scientists measured how well the chickens grew, tested their intestinal health, analyzed their gut bacteria, and measured inflammation markers in their blood and tissues.
This approach allowed researchers to compare how grape pomace performed against both a standard diet and antibiotic treatment. By using both fermented and non-fermented grape pomace, they could see if the fermentation process made the grape waste more effective. The study focused on the cecum—a part of the chicken’s digestive system—because that’s where most gut bacteria live and where short-chain fatty acids are produced.
This research design is important because it mimics real-world farming challenges. The high-fiber diet stresses the chicken’s digestive system and causes inflammation, similar to what happens when farms stop using antibiotics. By testing grape pomace against both this challenging condition and antibiotic treatment, researchers could see if the natural product could be a practical replacement. Understanding the specific bacteria and compounds involved (the microbiome-SCFA-immune pathway) helps explain how grape pomace works, not just that it works.
This study was published in a peer-reviewed scientific journal (NPJ Biofilms and Microbiomes), which means other experts reviewed the work before publication. The sample size of 126 chickens is reasonable for this type of animal research. However, this is a single study in a controlled laboratory setting with one breed of chicken, so the results may not apply to all poultry farming situations. The researchers measured multiple outcomes (growth, inflammation, bacteria, and fatty acids), which strengthens their conclusions. The study was conducted in 2026, making it current research.
What the Results Show
Chickens fed the challenging high-fiber diet without any additives showed clear signs of intestinal inflammation, including higher levels of inflammatory proteins (TNF-α and IL-1β) and reduced growth compared to chickens on standard feed. When researchers added grape pomace to the challenging diet, the inflammation markers dropped significantly, and the chickens grew much better—nearly as well as chickens given antibiotics.
The grape pomace worked by changing the types of bacteria living in the chickens’ guts. Specifically, it increased beneficial bacteria from the Lactobacillaceae family and boosted production of butyrate, a short-chain fatty acid that helps calm intestinal inflammation. Fermented grape pomace (treated with either beneficial bacteria or yeast) appeared slightly more effective than plain grape pomace, though both versions worked well.
The researchers identified a specific pathway: more Lactobacillaceae bacteria led to more butyrate production, which reduced inflammation (lower IL-1β levels) and improved growth. This chain of events explains how grape pomace protects chicken health. The study also found that grape pomace provided additional benefits beyond inflammation reduction—it contained antioxidants and acted as a prebiotic (food for beneficial bacteria).
The study found that fermented grape pomace versions (fermented with Lactobacillus casei bacteria or Saccharomyces cerevisiae yeast) produced slightly better results than non-fermented grape pomace, though the differences were modest. Both fermented versions improved the diversity and balance of gut bacteria. The researchers also noted that grape pomace’s polyphenol content (plant compounds with antioxidant properties) likely contributed to its anti-inflammatory effects beyond just the microbiome changes. The cecal microbiome changes were measurable and consistent across the grape pomace treatment groups.
This research builds on growing evidence that natural plant-based additives can reduce the need for antibiotics in poultry farming. Previous studies have shown that various polyphenol-rich foods can improve gut health in chickens, but this is among the first to specifically examine grape pomace and to identify the specific bacterial pathways involved. The finding that grape pomace performs comparably to antibiotics aligns with other research showing that microbiome-targeted interventions can replace growth-promoting antibiotics. However, most prior work focused on individual polyphenols rather than whole food byproducts like grape pomace.
This study was conducted in a controlled laboratory setting with a single breed of broiler chicken, so results may differ in commercial farms with different chicken breeds, management practices, or environmental conditions. The study lasted several weeks, which is typical for broiler chicken growth but doesn’t show long-term effects. The sample size of 126 chickens, while reasonable, is relatively small for drawing broad conclusions about an entire industry. The study didn’t examine whether grape pomace would work as well if chickens were exposed to disease-causing bacteria or viruses, which is common in real farms. Additionally, the cost-effectiveness of using grape pomace compared to antibiotics wasn’t evaluated, which would be important for farmers considering this switch.
The Bottom Line
Based on this research, grape pomace shows promise as a potential antibiotic replacement in poultry farming (moderate confidence level). The evidence suggests using 0.5% grape pomace in chicken feed could maintain growth and reduce inflammation without antibiotics. However, larger studies in commercial farm settings are needed before widespread adoption. Farmers interested in antibiotic-free production should consider this as one option among several, pending further research (low to moderate confidence for immediate implementation).
Poultry farmers transitioning to antibiotic-free production should pay attention to this research, as it offers a potential solution to maintaining bird health without antibiotics. Feed manufacturers and agricultural companies developing antibiotic alternatives would find this relevant. Consumers concerned about antibiotic use in food production may appreciate this development. However, backyard chicken keepers with small flocks may not find this practical, as grape pomace would need to be sourced in bulk. This research is less relevant to people raising other livestock species.
In this study, benefits appeared within the several-week growth period of broiler chickens. In practical application, farmers would likely see improvements in bird health and growth rates within 2-4 weeks of adding grape pomace to feed. However, the full benefits of improved microbiome balance might take longer to develop. Long-term effects beyond the typical broiler growth period (6-7 weeks) remain unknown.
Frequently Asked Questions
Can grape pomace really replace antibiotics in chicken farming?
This 2026 study of 126 chickens shows grape pomace performed as well as antibiotics at reducing inflammation and supporting growth. However, it’s one controlled study, so larger farm-based trials are needed before widespread replacement. It shows promise as part of antibiotic-free farming strategies.
How does grape pomace help chickens’ digestive health?
Grape pomace increases beneficial Lactobacillaceae bacteria in the chicken’s gut and boosts butyrate production—a compound that calms intestinal inflammation. The polyphenols (plant compounds) in grape skins also have antioxidant properties that reduce inflammation.
Is grape pomace safe for chickens to eat?
This study found no safety concerns with 0.5% grape pomace in chicken feed. Grape pomace is a food byproduct already used in some animal feeds. However, long-term safety data and testing in commercial farm conditions would strengthen confidence in its safety.
Would fermented grape pomace work better than regular grape pomace?
In this study, fermented grape pomace (treated with beneficial bacteria or yeast) showed slightly better results than non-fermented grape pomace, but both versions significantly reduced inflammation and improved growth compared to the control diet.
How much grape pomace do farmers need to add to chicken feed?
This research tested 0.5% grape pomace (half a percent by weight) mixed into feed and found it effective at reducing inflammation and supporting growth. Whether higher or lower percentages would work better remains unknown and would require additional testing.
Want to Apply This Research?
- For poultry farmers using a nutrition tracking app: Log daily feed composition (including grape pomace percentage), measure weekly bird weight gain, and track health indicators like mortality rate and disease incidence. Compare these metrics before and after introducing grape pomace to quantify the impact on your flock.
- If managing a farm: Switch 0.5% of your standard feed to grape pomace-supplemented feed and monitor your flock’s growth rate and health over 3-4 weeks. If you’re a consumer: Look for poultry products labeled as raised without antibiotics and ask producers if they use natural additives like grape pomace.
- Track bird growth rates (weight gain per week), feed conversion efficiency (how much feed produces how much meat), disease incidence, and mortality rates. Compare these metrics monthly before and after implementing grape pomace supplementation. For consumers, monitor how you feel after eating poultry from farms using natural alternatives to antibiotics—though individual health effects would be subtle and difficult to measure directly.
This research was conducted in controlled laboratory conditions with broiler chickens and may not directly apply to all poultry farming situations, different chicken breeds, or commercial farm environments. The study was relatively small (126 chickens) and lasted several weeks. Before implementing grape pomace as an antibiotic replacement on your farm, consult with a veterinarian or poultry nutritionist familiar with your specific operation. This article is for informational purposes and should not replace professional agricultural or veterinary advice. Results from animal studies do not automatically translate to human food safety or nutrition benefits, though they may inform future research directions.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.