Scientists tested a new supplement made from a special type of bacteria called Bacillus amyloliquefaciens F1 to help chickens grow better and stay healthier. Instead of using antibiotics, which can cause problems when overused, researchers gave some chickens this bacteria supplement for 9 weeks. The chickens that got the supplement grew about 7-8% faster, needed less food to gain weight, and had stronger immune systems. Their intestines also looked healthier under a microscope. This research suggests that this natural supplement could be a safe way to help chickens grow without relying on antibiotics.

The Quick Take

  • What they studied: Can a supplement made from special bacteria help chickens grow faster and healthier without using antibiotics?
  • Who participated: 360 young male yellow-feathered chickens that were randomly divided into three groups and studied for 9 weeks
  • Key finding: Chickens that received the bacteria supplement grew about 7.5% heavier by week 3, gained weight 8% faster, and needed 9% less food to gain the same amount of weight compared to chickens without the supplement
  • What it means for you: This research suggests that natural bacteria supplements could replace antibiotics in chicken farming, which is important because overusing antibiotics creates bacteria that are harder to treat. However, this study was only done on chickens, so we don’t yet know if similar benefits would apply to other animals or humans.

The Research Details

Researchers divided 360 young chickens into three equal groups. One group ate regular chicken feed (the control group), while the other two groups ate the same feed but with added bacteria supplement at two different amounts: 100 grams per ton and 150 grams per ton. All chickens were raised under the same conditions for 63 days (9 weeks), and researchers measured how much they weighed, how much food they ate, and checked their blood and intestines at different time points.

The bacteria supplement used in this study isn’t a live bacteria—it’s called a ‘postbiotic,’ which means it’s made from the byproducts that bacteria create. This makes it safer and more stable than using live bacteria, since it won’t change or grow in unexpected ways.

Researchers measured several important things: how fast the chickens grew, how efficiently they converted food into body weight, the health of their intestines by looking at them under a microscope, their blood chemistry, and the types of bacteria living in their digestive systems.

This research matters because antibiotics have been overused in chicken farming for decades, which has created antibiotic-resistant bacteria that are dangerous to both animals and humans. Finding safe, natural alternatives is important for food safety and public health. The study design is solid because it compared treated and untreated groups under identical conditions, making it easier to see if the supplement actually caused the improvements.

This study has several strengths: it used a large number of animals (360), had a clear control group for comparison, and measured multiple important outcomes (growth, immunity, intestinal health, and gut bacteria). The study was published in a respected scientific journal focused on poultry science. However, the study only looked at one type of chicken breed, so results might be different for other breeds. The researchers also didn’t test this supplement in combination with other treatments, so we don’t know how it might interact with other farm practices.

What the Results Show

The chickens that received the bacteria supplement grew noticeably faster than the control group. By week 3, chickens getting the supplement weighed about 7.5% more than the control chickens, and they were gaining weight about 8% faster each day. Even more impressive, these chickens needed 9% less food to gain the same amount of weight, which means the supplement made them more efficient at converting food into body weight—an important measure of health and efficiency in farming.

The supplement also boosted the chickens’ natural defense systems. Blood tests showed that chickens receiving the supplement had stronger antioxidant enzymes (special proteins that protect cells from damage). Specifically, three important protective enzymes increased by 24-31%, while a harmful substance called malondialdehyde (which damages cells) decreased by about 40%. This suggests the supplement helped protect the chickens’ bodies from internal damage.

When researchers looked at the chickens’ intestines under a microscope, they found that the supplement improved intestinal structure. The finger-like projections in the intestines (called villi) were taller and had better proportions in chickens that received the supplement. This is important because taller villi help chickens absorb more nutrients from their food. The supplement also increased production of a protective mucus layer in the intestines, which acts like a shield against harmful bacteria.

Finally, the supplement changed the types of bacteria living in the chickens’ digestive systems in beneficial ways, though it didn’t change the total number of different bacteria species present.

The study found that the 100 g/t dose appeared to work slightly better than the 150 g/t dose for early growth benefits, suggesting there may be an optimal amount to use. The improvements in intestinal health and immune function were consistent across both supplement doses, indicating that even the lower dose provided meaningful benefits. The changes in gut bacteria composition suggest the supplement works partly by helping beneficial bacteria grow while limiting harmful ones.

This research builds on growing evidence that probiotics and postbiotics (bacteria-based supplements) can improve animal health without antibiotics. Previous studies have shown similar benefits with other bacterial supplements, but this is one of the first to thoroughly examine this specific Bacillus amyloliquefaciens strain in yellow-feathered chickens. The findings align with the broader scientific consensus that natural alternatives to antibiotics are both possible and effective.

This study only tested one type of chicken breed (yellow-feathered broilers), so the results might not apply to other chicken breeds or types of poultry. The research was conducted in a controlled farm setting, which may not reflect real-world conditions on all farms. The study didn’t compare the bacteria supplement directly to antibiotics, so we can’t say whether it works as well as antibiotics. Additionally, the study only lasted 9 weeks, so we don’t know if the benefits continue longer or if chickens build up tolerance over time. Finally, this research was done on chickens, so we can’t assume these benefits would apply to other animals or humans without additional studies.

The Bottom Line

Based on this research, the 100 g/t dose of Bacillus amyloliquefaciens F1 postbiotics appears to be the most effective amount for promoting early growth and health in yellow-feathered chickens. This is a promising alternative to antibiotics for chicken farming. However, these findings are specific to this chicken breed and farming conditions, so farmers should consider testing the supplement on their own farms before making large-scale changes. Confidence level: Moderate—this is solid research, but it’s limited to one chicken type and one farm setting.

Chicken farmers and poultry producers should care about this research because it offers a practical way to improve chicken health and growth without relying on antibiotics. Food safety officials and public health professionals should care because reducing antibiotic use in farming helps prevent antibiotic-resistant bacteria. Consumers concerned about antibiotic use in food production should care because this research supports alternatives. However, this research doesn’t directly apply to people raising backyard chickens or to other types of livestock without further study.

Based on this study, farmers could expect to see improvements in chicken growth within 2-3 weeks of starting the supplement. The benefits to intestinal health and immune function appear to develop over the full 9-week period studied. However, it’s unclear how long these benefits last after the supplement is stopped or whether they continue to improve beyond 9 weeks.

Want to Apply This Research?

  • If you’re a farmer using this supplement, track weekly body weight gains and feed conversion ratios (amount of feed needed per pound of weight gained) to measure whether the supplement is working as expected on your farm.
  • For farmers: Consider implementing a trial period where you supplement feed for one flock while keeping another flock as a control group, then compare growth rates and feed efficiency between the two groups to see if results match this research on your specific farm.
  • Monitor intestinal health indicators indirectly by tracking feed intake, water consumption, and any signs of digestive problems. Keep detailed records of growth rates and feed conversion ratios throughout the 9-week period to identify when benefits appear and whether they plateau over time.

This research was conducted on chickens and may not apply to other animals or humans. The study was performed in controlled farm conditions and results may vary on different farms or with different chicken breeds. This supplement should not be considered a replacement for veterinary care or medical treatment. Farmers should consult with a veterinarian or poultry nutrition specialist before making changes to their feeding programs. This research does not constitute medical advice for humans and should not be used to make health decisions for people. Always follow local regulations regarding feed additives and consult with appropriate professionals before implementing new farming practices.