According to Gram Research analysis of a 2026 Poultry Science study, adding a traditional Chinese medicinal vine to young laying hens’ feed improved their laying rate and egg quality. In a six-week trial of 252 hens, the fermented form gave the largest egg quality gains, and both forms reduced the feed needed for each unit of egg output.
A new study in Poultry Science, reviewed by Gram Research, tested whether leaves and stems of a traditional Chinese medicinal vine, Tetrastigma hemsleyanum, could improve egg production in young laying hens. Researchers divided 252 hens into three groups for six weeks: a standard diet, a diet with 1% of the plant, and a diet with 1% of the fermented plant. Both plant versions increased the number of eggs laid and reduced the amount of feed needed per unit of egg output. The fermented version also produced thicker egg whites, a sign of fresher eggs, and showed healthier intestines and gut bacteria. The results are promising for poultry farming, but this was an animal study, so the findings cannot yet be applied to people.
Key Statistics
A 2026 study published in Poultry Science found that feeding 1% fermented Tetrastigma hemsleyanum to 252 laying hens over six weeks produced higher albumen height and Haugh unit scores, measures of egg white thickness and freshness, than a standard diet.
In a six-week animal trial of 252 Hy-Line Brown hens, adding 1% of the herb to the diet significantly increased laying rate and lowered feed conversion ratio compared with a standard diet (P less than 0.05).
The same 2026 hen study reported that both herb-supplemented groups had fewer potentially harmful gut bacteria, including Proteobacteria and Desulfobacterota, than hens on a standard diet, though the findings apply only to hens.
The Quick Take
- What they studied: Can adding the leaves and stems of a traditional Chinese medicinal vine to hen feed, in fresh or fermented form, improve egg production, egg quality, body defenses against cell damage, and gut health?
- Who participated: 252 Hy-Line Brown hens, a common egg-laying breed, starting at about 19 weeks old. The hens were split randomly into three groups of 84, and each group was further divided into four smaller pens of 21 hens.
- Key finding: Both the fresh and fermented plant supplements increased how often hens laid eggs and reduced feed needed per unit of egg output. The fermented version gave the strongest gains in egg white thickness and gut lining health. All comparisons with the standard diet were statistically significant, meaning the differences were unlikely to be due to chance.
- What it means for you: If you raise backyard or commercial hens, this research suggests that a small amount of this herb in feed may help your flock lay more efficiently and produce higher quality eggs. The study does not show direct health benefits for people who eat these eggs or take the herb.
The Research Details
Researchers wanted to know whether the leaves and stems of Tetrastigma hemsleyanum, a plant that has been studied mostly for its roots, could benefit laying hens. They used 252 young hens and randomly assigned them to one of three diets. The control group ate a standard feed with no added herb. The second group ate standard feed with 1% of the dried plant mixed in. The third group ate standard feed with 1% of a fermented version of the plant, which had been treated with microbes to change how it breaks down in the body.
The experiment lasted six weeks. The first week was an adjustment period so the hens could get used to their new diets. During the remaining weeks, the team recorded how many eggs each group laid, how much feed they ate, and the quality of the eggs. At the end of the study, they examined the hens’ livers, reproductive tracts, and intestines, and analyzed the bacteria living in their digestive systems.
Because the hens were assigned to groups by chance and each group had several pens, the design helps reduce the chance that differences came from pre-existing traits in the birds. The researchers then used standard statistical tests to compare the groups.
Randomly assigning the hens to groups is a key strength. It makes the groups similar at the start, so any differences seen at the end are more likely to come from the diet itself. Measuring many outcomes at once, from egg shell and white quality to tissue and gut bacteria, gives a fuller picture of how the herb works. Testing both fresh and fermented forms also shows whether processing changes the benefits, which is useful for farmers deciding which product to buy.
This is a controlled experiment, which is stronger than a simple observation of farms. The sample of 252 hens is reasonable for an animal feeding trial, and results were reported with statistical tests. However, the study was conducted on one breed, over a short six-week window, and likely at a single research site. The paper reports that its findings are statistically significant, but the full data, exact effect sizes, and long-term outcomes are only available in the complete article. Readers should treat the results as a strong starting point rather than final proof.
What the Results Show
The clearest result was in egg production. Both the fresh and fermented herb groups laid eggs at a higher rate than the control group. At the same time, they needed less feed to produce each unit of egg output, which is measured by a number called the feed conversion ratio. A lower number here means the hens turned feed into eggs more efficiently, which matters a great deal for farm profits.
Egg quality also improved, especially in the fermented group. Albumen height and Haugh unit, two measures of how thick and fresh the egg white is, were higher in hens eating the fermented herb than in the other two groups. Thicker egg whites generally indicate fresher eggs that are better for sale and for cooking.
The researchers also looked inside the hens. Both herb groups showed higher levels of certain antioxidant enzymes in the liver and in the magnum, the part of the hen’s reproductive tract that makes egg white. Antioxidants help cells resist damage from normal metabolism, so this suggests the herb may help the birds’ bodies manage stress. The fermented group also had thicker intestinal walls and taller, healthier-looking villi, the tiny finger-like structures that absorb nutrients.
Finally, the gut bacteria changed. Both herb groups had fewer bacteria linked to potential harm, such as Desulfobacterota and Proteobacteria, and more of a beneficial group called Bacteroidales. Because the gut microbiome is closely tied to nutrient absorption and immunity, these shifts may help explain the better performance, although the study did not prove a direct cause.
The fermented herb showed stronger effects than the fresh herb, particularly on the health of the small intestine. Taller intestinal villi mean more surface area for absorbing nutrients, which may help explain why the fermented group did well on egg quality. Antioxidant improvements in the liver and reproductive tract were seen in both herb groups, suggesting the plant itself carries useful compounds, while fermentation seemed to boost certain benefits further. These secondary results point to a whole-body effect rather than a single narrow change.
Many studies have examined herbal and plant-based feed additives in poultry, and researchers have often found that fermentation can make plant compounds easier to absorb. This study fits that pattern, since the fermented form generally outperformed the fresh form. Earlier research on this plant has focused mainly on its roots and its potential medicinal uses in people, so this work extends that knowledge to the aerial parts and to animal nutrition. Because the study is new, it adds to the evidence base rather than settling the question.
The study used one breed of hen and ran for only six weeks, so it is unclear whether the benefits last through a full laying cycle or apply to older birds, other breeds, or different climates. The herb was tested at only one inclusion level, 1% of the diet, so we do not know whether higher or lower amounts would work better or cause problems. The study was also done in animals, so it cannot tell us whether eating eggs from these hens affects human health. Finally, the exact mechanisms linking the herb, gut bacteria, and egg quality are still being worked out, and the full statistical details should be checked in the original paper.
The Bottom Line
Based on this single animal study, there is moderate confidence that adding 1% of the fermented or fresh herb to a standard layer diet may improve laying rate, feed efficiency, and egg white quality in young hens. Confidence is lower for the gut and antioxidant findings, which need confirmation through repeat studies. Farmers should consider a small trial on their own flock before changing feed on a large scale, and should work with a poultry nutritionist or veterinarian.
Commercial egg producers, small-scale poultry keepers, and feed manufacturers are the groups most likely to find this research useful. People who are interested in natural feed additives or sustainable farming may also find it relevant. This research does not provide health guidance for people who eat eggs, take the herb as a supplement, or use it in traditional medicine. Anyone with health concerns should talk with a qualified healthcare professional rather than rely on this study.
In a six-week trial, changes in egg production and feed efficiency were measured during the study period. Farmers who try this approach should expect to track results over at least one full laying cycle before judging whether the benefits are consistent. Improvements in gut health and antioxidant levels develop more gradually and would be expected to build over time, rather than appearing within days.
Frequently Asked Questions
Does adding a Chinese medicinal herb to chicken feed improve egg production?
Research shows that adding 1% of Tetrastigma hemsleyanum to feed increased laying rate in a six-week study of 252 young hens. The same diets also needed less feed per unit of egg output. These results come from one animal study and need repeat testing before wider use.
Which form of the herb works better for laying hens, fresh or fermented?
In a 2026 study of 252 laying hens, the fermented form of Tetrastigma hemsleyanum produced stronger effects than the fresh form. Fermented feed gave higher egg white thickness scores and healthier small intestine structure. Both forms improved laying rate and feed efficiency compared with standard feed.
Can eating eggs from hens fed this herb benefit my health?
The study tested hen health and egg quality, not human health. It did not measure whether eating these eggs affects people. Anyone interested in health effects should consult a qualified healthcare professional rather than rely on this animal feeding research.
How long does it take for hens to show benefits from this herb supplement?
In the six-week study of 252 hens, production and feed efficiency changes were measured within the trial period. Gut and antioxidant improvements typically develop more gradually. Experts suggest tracking results across a full laying cycle before judging long-term effects.
Want to Apply This Research?
- Record each flock’s daily egg count, total feed weight used per week, and the percentage of eggs with a Haugh unit score (or similar freshness measure) checked once a week. Compare these numbers against a control period or a control pen fed standard feed. Calculating feed used per dozen eggs each week gives a simple, measurable efficiency score.
- Set up a two-pen comparison: one pen on standard feed and one on feed with 1% of the herb, both with the same number of hens. Log daily egg counts and feed use in the app for at least six weeks. Use the app’s weekly summary to see whether the treated pen shows a higher laying rate and lower feed per dozen eggs.
- Continue logging laying rate, feed efficiency, and egg quality over a full laying cycle, and add a monthly check on egg freshness and flock health notes such as droppings, feather condition, and any illness. Review the data every quarter, and share results with a veterinarian or poultry nutritionist before making long-term feed changes. Keep records of any feed brand or herb batch changes so results can be interpreted accurately.
This article summarizes an animal study on laying hens published in Poultry Science. The findings apply to poultry farming and have not been tested for human health effects. Nothing in this article is veterinary or medical advice. Farmers should consult a licensed veterinarian or poultry nutritionist before changing feed, and people with health questions should speak with a qualified healthcare professional.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.