According to Gram Research analysis, guanidinoacetic acid (GAA) supplementation helps broiler chickens maintain normal growth and improve gut health even when fed diets with 50-75 fewer calories per kilogram than standard feed. In a study of 9,500 chickens, those receiving 0.06% GAA supplementation on reduced-energy diets performed nearly as well as chickens on normal-energy feed, suggesting the supplement could help farms reduce feed costs without sacrificing chicken health.
Researchers tested a natural supplement called guanidinoacetic acid (GAA) to see if it could help chickens grow normally even when their feed had less energy. They fed 9,500 chickens different diets for 41 days—some with normal energy levels, some with reduced energy, and some with reduced energy plus the GAA supplement. The results showed that adding GAA helped chickens maintain healthy growth and better gut bacteria even when eating lower-energy feed. This finding could help farmers reduce feed costs while keeping chickens healthy, and the research suggests similar benefits might apply to other animals too.
Key Statistics
A 2026 study of 9,500 broiler chickens found that adding 0.06% guanidinoacetic acid to reduced-energy diets maintained growth performance and feed efficiency comparable to standard-energy diets, potentially allowing farms to reduce feed costs by up to 75 calories per kilogram.
Research on 9,500 broilers showed that reduced-energy diets without guanidinoacetic acid supplementation significantly increased feed conversion ratio (requiring more feed per pound of growth) during the final growth phase, but GAA supplementation reversed this negative effect.
In a large-scale study of 9,500 chickens, guanidinoacetic acid supplementation improved beneficial gut bacteria counts in chickens fed reduced-energy diets, while reducing harmful bacteria levels to approach those of chickens on normal-energy feed.
The Quick Take
- What they studied: Whether a natural compound called guanidinoacetic acid (GAA) could help broiler chickens grow normally when fed diets with less energy than usual.
- Who participated: 9,500 one-day-old Ross 308 broiler chickens (equal numbers of males and females) divided into 5 groups, with 10 pens per group containing 190 chickens each. The study lasted 41 days, which is the typical growing period for meat chickens.
- Key finding: Chickens given GAA supplementation maintained normal growth and better gut health even when their feed had 50-75 fewer calories per kilogram compared to standard feed. Without the supplement, reduced-energy diets caused slower growth and worse feed efficiency.
- What it means for you: This research suggests that farms could potentially reduce feed costs by using lower-energy diets supplemented with GAA without sacrificing chicken health or growth. However, this finding applies specifically to commercial chicken production and would need further testing before broader application.
The Research Details
Researchers divided 9,500 young broiler chickens into five equal groups and fed them different diets for 41 days. One group received standard feed with normal energy levels (the positive control). Two groups received feed with reduced energy—one reduced by 50 calories per kilogram and another by 75 calories per kilogram. The remaining two groups received the same reduced-energy feeds but with an added 0.06% supplement of guanidinoacetic acid (GAA), a natural compound that helps with muscle development and energy use.
Throughout the study, researchers measured how much feed the chickens ate, how much they grew, how efficiently they converted feed into body weight, and the quality of their gut bacteria. They also examined the chickens’ organs and body composition at the end of the study. Each treatment group had 10 separate pens with 190 chickens per pen, which helps ensure the results are reliable and not due to chance.
This design is strong because it uses a large number of animals, multiple replicate groups, and clear comparison points. The researchers could directly compare how chickens performed on normal-energy feed versus reduced-energy feed, and then see how the GAA supplement affected those results.
This research approach matters because it tests a practical, real-world scenario that farmers face: how to reduce feed costs without harming animal health. By using a large number of chickens in a controlled setting, the researchers could detect even small differences in growth and health that might not show up in smaller studies. The study also measured multiple important outcomes—not just growth, but also gut health and feed efficiency—which gives a complete picture of how the supplement works.
This study has several strengths: it used a very large sample size (9,500 chickens), included multiple replicate groups to reduce random variation, measured multiple relevant outcomes, and lasted the full commercial growing period. The study was published in a peer-reviewed journal, meaning other experts reviewed the methods and results. However, the study focused only on one breed of chicken (Ross 308) and one specific supplement dose (0.06% GAA), so results might differ with other breeds or doses. The study also doesn’t explain the exact biological mechanisms of how GAA works, only that it does work.
What the Results Show
When researchers reduced the energy in chicken feed by 50 or 75 calories per kilogram, the chickens grew more slowly and needed more feed to gain each pound of body weight—a measure called feed conversion ratio (FCR). Specifically, during the final growth phase (days 25-41) and across the entire 41-day period, chickens on reduced-energy diets without the supplement had significantly worse feed conversion than chickens on normal-energy feed.
However, when researchers added the GAA supplement to the reduced-energy diets, the results changed dramatically. Chickens receiving GAA-supplemented feed performed nearly as well as chickens on normal-energy feed. They grew at similar rates and converted feed to body weight almost as efficiently. This suggests that the GAA supplement compensated for the missing calories in the feed.
The researchers also examined gut health by measuring beneficial bacteria in the chickens’ digestive systems. Reduced-energy diets without the supplement led to decreased beneficial bacteria and increased harmful bacteria. But when GAA was added, the gut bacteria profile improved significantly, approaching levels similar to chickens on normal-energy feed. This is important because healthy gut bacteria help chickens absorb nutrients better and stay healthier overall.
The study found that carcass yield (the amount of usable meat), cut yields (specific meat portions), and abdominal fat percentage were not significantly affected by any of the dietary treatments. This means that while energy reduction affected how efficiently chickens converted feed, it didn’t change the final meat quality or composition. Interestingly, liver weight increased in all treatment groups compared to the positive control, though the researchers didn’t fully explain why this occurred. The key secondary finding was that GAA supplementation improved the balance of bacteria in the gut, with beneficial bacteria increasing and harmful bacteria decreasing when the supplement was added to reduced-energy diets.
This research builds on earlier studies showing that guanidinoacetic acid can improve muscle development and energy efficiency in various animals. Previous research suggested GAA might help animals perform better under stress or challenging conditions, but this is one of the first large-scale studies testing whether it can compensate for reduced dietary energy in commercial broiler chickens. The findings align with the theory that GAA helps animals use available energy more efficiently, but this study provides the first strong evidence that it can do so at a practical, commercial scale with a very large number of animals.
While this study is large and well-designed, it has some important limitations. First, it tested only one breed of chicken (Ross 308) and one dose of GAA (0.06%), so results might differ with other breeds or different supplement amounts. Second, the study lasted only 41 days, which is the typical commercial growing period, but doesn’t tell us about long-term effects if chickens were raised longer. Third, the study doesn’t fully explain the biological mechanisms of how GAA works—it shows that it works, but not exactly why at the cellular level. Finally, the study was conducted in a controlled research setting; results on actual farms might differ due to variations in management, environment, and other factors.
The Bottom Line
Based on this research, farmers could consider supplementing reduced-energy broiler diets with 0.06% guanidinoacetic acid as a cost-saving strategy. The evidence is strong (from a large, well-designed study) that this approach maintains growth performance and improves gut health. However, farmers should start with small trials on their own farms before making large-scale changes, as results may vary based on their specific conditions, chicken breeds, and feed sources. Consulting with a poultry nutritionist is recommended before implementing this strategy.
This research is most relevant to commercial broiler chicken farmers looking to reduce feed costs. It may also interest poultry nutritionists, feed manufacturers, and agricultural researchers. The findings might eventually apply to other livestock species, but that would require additional research. This research does not directly apply to backyard chicken keepers or people raising chickens for eggs rather than meat, as the study focused specifically on meat-type broilers.
In this study, the benefits of GAA supplementation appeared throughout the 41-day growing period, with the most noticeable improvements in feed efficiency during the final growth phase (days 25-41). On a farm, benefits would likely appear within the first few weeks of switching to the supplemented diet, though the most significant cost savings would accumulate over the entire growing period. Farmers should expect to see measurable improvements in feed conversion within 2-3 weeks of starting the supplement.
Frequently Asked Questions
Can guanidinoacetic acid really help chickens grow normally on cheaper feed?
Research shows that 0.06% GAA supplementation allows broiler chickens to maintain normal growth and feed efficiency on diets with 50-75 fewer calories per kilogram than standard feed. A study of 9,500 chickens demonstrated this effect across the entire 41-day growing period.
Does reducing feed energy hurt chicken health?
Reduced-energy diets without supplementation decreased beneficial gut bacteria and increased harmful bacteria in broilers. However, adding GAA supplementation reversed these negative effects, improving the gut bacteria balance to levels similar to chickens on normal-energy feed.
What is guanidinoacetic acid and is it safe for chickens?
Guanidinoacetic acid (GAA) is a natural compound that helps animals use energy more efficiently and develop muscle. This study used 0.06% GAA supplementation in broiler feed with no reported safety concerns, and the supplement improved both growth performance and gut health.
How much money could farms save by using this supplement?
While this study didn’t calculate exact cost savings, reducing feed energy by 75 calories per kilogram while maintaining growth through GAA supplementation could significantly lower feed costs, which typically represent 60-70% of broiler production expenses. Actual savings depend on local feed and supplement prices.
Would this work for other types of chickens or animals?
This study tested only Ross 308 broiler chickens (meat-type birds). While GAA may benefit other animal species, additional research would be needed to confirm effectiveness in other chicken breeds, laying hens, or livestock like pigs or cattle.
Want to Apply This Research?
- Track daily feed consumption and weekly body weight gains for each flock group, calculating feed conversion ratio (pounds of feed per pound of weight gained) every 7 days to monitor whether the GAA supplement is delivering expected efficiency improvements.
- If managing a poultry operation, implement a trial period using GAA-supplemented reduced-energy feed in one section of your flock while maintaining standard feed in another section, comparing feed costs and growth metrics weekly to determine if the strategy works for your specific operation.
- Establish a baseline of your current feed costs and growth performance, then track these metrics weekly after introducing GAA supplementation. Monitor gut health indicators indirectly by observing flock health, mortality rates, and feed intake patterns. Compare your results to the baseline every 2-3 weeks to determine if the supplement is delivering the expected benefits.
This research applies specifically to commercial broiler chicken production and was conducted in controlled research settings. Results may vary based on chicken breed, farm conditions, feed sources, and management practices. Farmers should consult with a poultry nutritionist or veterinarian before making significant changes to their feeding programs. This information is not intended to replace professional agricultural or veterinary advice. The study measured outcomes in chickens only; safety and effectiveness in other animals or species has not been established by this research.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.