Chasteberry essential oil significantly improves broiler chicken growth, immune function, and gut health when added to feed. A 2026 study of 320 chickens found that oil supplementation at 0.5 to 1.0 milliliters per kilogram of feed increased final body weight, reduced harmful liver and kidney markers, improved cholesterol profiles, boosted antioxidant protection, and increased beneficial gut bacteria while reducing harmful bacteria like E. coli. According to Gram Research analysis, these improvements suggest chasteberry oil functions as an effective natural feed additive for poultry production.
Researchers tested whether an oil from the chasteberry plant could improve the health of broiler chickens, the kind raised for meat. They gave 320 baby chickens either regular feed or feed mixed with different amounts of this natural oil over 35 days. According to Gram Research analysis, the chickens that received the oil grew bigger, had better immune systems, and developed healthier gut bacteria compared to chickens eating regular feed. The oil also reduced harmful substances in their bodies and improved their overall health markers. This finding suggests that natural plant oils could be a safe alternative to synthetic additives in chicken farming.
Key Statistics
A 2026 study of 320 broiler chickens found that dietary chasteberry oil supplementation at 0.5 to 1.0 mL/kg significantly increased final live body weight and total body weight gain compared to control chickens receiving no oil.
Research on 320 chickens showed that chasteberry oil supplementation quadratically enhanced antioxidant enzyme activities (SOD, TAC, and GPx) while suppressing oxidative damage markers like malondialdehyde and protein carbonyl.
A 2026 broiler chicken study demonstrated that all doses of chasteberry oil reduced harmful bacteria populations, with marked reductions in Escherichia coli and Clostridium species in the cecal microbiota compared to control birds.
Chasteberry oil supplementation in 320 chickens improved lipid profiles by significantly reducing total cholesterol and triglycerides while elevating beneficial HDL cholesterol, particularly at 0.5 and 1.0 mL/kg doses.
The Quick Take
- What they studied: Whether adding chasteberry essential oil to chicken feed would improve growth, health, immune function, and gut bacteria in broiler chickens
- Who participated: 320 one-day-old baby chickens (Cobb breed) divided into four groups that received different amounts of the oil or no oil at all over 35 days
- Key finding: Chickens receiving the oil grew significantly heavier, had stronger immune systems, better antioxidant protection, and healthier gut bacteria compared to control chickens, with the best results at medium to high doses
- What it means for you: This research suggests natural plant oils could improve chicken health on farms, potentially leading to healthier meat products. However, this is animal research, so human benefits would need separate testing
The Research Details
Scientists divided 320 newly hatched chickens into four equal groups. One group received normal chicken feed as a control. The other three groups received the same feed but with different amounts of chasteberry oil mixed in: a small amount, a medium amount, or a larger amount. All chickens were raised for 35 days under identical conditions. The researchers measured how much the chickens grew, tested their blood for signs of health or disease, examined their gut bacteria, and checked their immune system strength.
The chasteberry oil itself was analyzed using a special laboratory technique called GC-MS, which identified the main active ingredients in the oil. These ingredients include natural compounds like oleic acid and linolenic acid, which are known to have health benefits.
This type of study is called a dose-response trial because it tests whether different amounts of a substance produce different effects. By comparing all four groups, the researchers could determine the best amount of oil to use and confirm that the oil itself, not something else, caused the improvements.
Testing different doses helps scientists find the sweet spot where a treatment works best without wasting resources or causing problems. By measuring many different health markers in the chickens’ blood and gut, the researchers could understand exactly how the oil affects the whole body, not just one thing. This thorough approach makes the findings more reliable and useful for farmers considering using this oil
The study used a large sample size of 320 chickens, which reduces the chance that results happened by accident. All chickens started at the same age and weight, and all groups were treated identically except for the oil dose, which strengthens the comparison. The researchers measured many different health outcomes using established laboratory methods, making the results more comprehensive. However, this study was conducted only in chickens, so results may not directly apply to other animals or humans
What the Results Show
Chickens that received the chasteberry oil grew significantly heavier than control chickens. The effect followed a pattern where medium and high doses produced the best growth results. Feed intake also increased with oil supplementation, suggesting the chickens ate more when the oil was added.
Blood tests showed major improvements in liver and kidney health markers. Chickens receiving the oil had lower levels of creatinine and urea, which indicate kidney function, and lower levels of liver enzymes that signal damage. These improvements appeared at all oil doses tested.
The oil dramatically improved cholesterol and fat profiles in the chickens’ blood. Total cholesterol and triglycerides decreased significantly, while beneficial HDL cholesterol increased. These changes are similar to what doctors want to see in human health.
Antioxidant protection increased substantially in all oil-treated groups. Antioxidants are natural substances that protect cells from damage. The oil boosted three key antioxidant enzymes while reducing markers of cellular damage, suggesting the chickens’ bodies were better protected from harmful oxidative stress.
The oil strengthened the chickens’ immune systems by increasing antibody levels in their blood. Antibodies are proteins that fight infections and disease. The oil also reduced inflammatory markers, meaning there was less inflammation in the chickens’ bodies. Inflammation is the body’s response to injury or infection, and excessive inflammation can harm health.
Gut bacteria analysis revealed that the oil increased the total number of beneficial bacteria while reducing harmful bacteria like E. coli and Clostridium species. A healthy gut microbiota, the community of bacteria living in the digestive system, is crucial for nutrient absorption and immune function.
This research aligns with previous studies showing that essential oils from plants can improve animal health and performance. The specific benefits observed here, particularly improvements in antioxidant status and gut bacteria composition, match findings from other natural feed additives. However, this is one of the first studies to comprehensively evaluate chasteberry oil in chickens, making it a novel contribution to the field
This study was conducted only in chickens, so results cannot be directly applied to humans or other animals without additional research. The study lasted only 35 days, so long-term effects are unknown. The research was conducted in a controlled laboratory setting, which may differ from real farm conditions where chickens face more stress and variable environments. The study did not evaluate whether the improvements in chicken health translate to benefits for people who consume the meat
The Bottom Line
Based on this research, chasteberry oil at doses of 0.5 to 1.0 milliliters per kilogram of feed appears to be the most effective for improving broiler chicken health. This recommendation has moderate to strong confidence because the study was well-designed with a large sample size and measured multiple health outcomes. However, farmers should consult with veterinarians before implementing this change, and further research in real farm settings would strengthen confidence in these recommendations
Poultry farmers and the chicken industry should pay attention to these findings as a potential natural alternative to synthetic feed additives. Consumers interested in naturally raised chicken products may find this relevant. Veterinarians and animal nutritionists should consider this research when advising clients. This research does not yet apply to human nutrition, so individual consumers should not assume they would receive the same benefits from consuming chasteberry oil
In the chickens studied, improvements in growth and health markers appeared within the 35-day study period. Farmers implementing this oil would likely see changes in chicken growth rates and feed efficiency within weeks. However, the long-term sustainability of these benefits and effects in different farming conditions remain unknown
Frequently Asked Questions
Can chasteberry oil improve human health the same way it improved chicken health in this study?
This study tested chasteberry oil only in chickens, so human benefits cannot be assumed without separate research. While the oil showed promise in animal studies, human trials would be needed to determine if similar health improvements occur in people
What is the best dose of chasteberry oil to give to chickens based on this research?
The research identified 0.5 to 1.0 milliliters of chasteberry oil per kilogram of feed as the optimal dose, producing the best improvements in growth, health markers, and gut bacteria while avoiding excessive feed intake
Does chasteberry oil reduce harmful bacteria in the chicken gut?
Yes, the study found that all doses of chasteberry oil significantly reduced harmful bacteria like E. coli and Clostridium species while increasing total beneficial bacteria counts in the chickens’ digestive systems
How long does it take to see improvements in chicken health from chasteberry oil?
In this 35-day study, improvements in growth, immune function, and gut bacteria appeared within the study period, suggesting farmers could observe benefits within weeks of adding the oil to feed
Is chasteberry oil safe to use as a chicken feed additive?
This study found no harmful effects at the tested doses, and the oil improved multiple health markers. However, farmers should consult veterinarians before implementation, and long-term safety in real farm conditions requires additional research
Want to Apply This Research?
- For farmers using this oil, track weekly chicken weight gain, feed conversion ratio (how much feed produces how much growth), and mortality rates. Compare these metrics before and after introducing the oil to quantify improvements
- Farmers could implement a gradual introduction of chasteberry oil into their feed supply, starting at the recommended 0.5 mL/kg dose and monitoring chicken health and growth performance over a 4-week period before deciding whether to continue
- Establish baseline health metrics for your flock, then measure the same metrics weekly after introducing the oil. Track growth rates, feed consumption, visible health signs, and any changes in mortality or disease. Keep detailed records to determine if the investment in the oil produces sufficient returns
This research was conducted in chickens and does not directly apply to human health or nutrition without additional human studies. Farmers considering using chasteberry oil should consult with veterinarians and animal nutritionists before implementation. This article summarizes research findings and should not be considered medical or veterinary advice. Individual results may vary based on farming conditions, chicken breed, and other environmental factors. Always follow local regulations regarding feed additives and consult with qualified professionals before making changes to animal feed
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.