Researchers tested whether adding two types of natural acids to chicken feed could help broiler chickens (chickens raised for meat) grow better and stay healthier. They compared four groups of chickens: one with regular feed and three groups that received different combinations of formic acid and citric acid mixed into their food. The chickens that got a combination of both acids grew the fastest, had better digestion, and showed stronger immune systems. The study suggests these natural acids could be a safer alternative to antibiotics that farmers currently use to help chickens grow.

The Quick Take

  • What they studied: Whether adding formic acid and citric acid (two types of natural acids found in foods) to chicken feed would help broiler chickens grow faster, have better digestion, and stay healthier without using antibiotics.
  • Who participated: 360 one-day-old broiler chicks divided into four equal groups of 90 chicks each. Each group was split into six smaller groups of 15 chicks to make sure the results were reliable.
  • Key finding: Chickens that received a mix of both acids (formic and citric) grew the fastest and converted their feed into body weight most efficiently. All acid-treated groups performed better than the control group with no added acids.
  • What it means for you: If you eat chicken, this research suggests farmers may soon have a safer, more natural way to raise healthier chickens without relying on antibiotics. This could mean better quality chicken meat in the future, though more research in real farm settings is needed to confirm these benefits.

The Research Details

Scientists divided 360 newly hatched chicks into four groups. One group (the control) ate regular chicken feed with nothing added. The second group’s feed had formic acid and sodium formate added. The third group’s feed had citric acid and sodium citrate added. The fourth group got a combination of both acids at lower amounts. Each group was further divided into six smaller groups of 15 chicks to ensure accurate results. The researchers then measured how fast the chickens grew, how efficiently they converted feed into body weight, and checked their blood for signs of health and immune strength over the study period.

This type of study is called a controlled experiment because it compares groups receiving different treatments to a control group that receives no treatment. This design helps researchers figure out whether the acids actually caused the improvements they observed, rather than other factors being responsible.

The researchers measured several important health markers including growth rate, feed efficiency, antioxidant levels (which protect cells from damage), immune response to common chicken diseases, and the types of bacteria living in the chickens’ digestive systems.

This research approach matters because it tests whether natural alternatives to antibiotics can work as well as or better than current methods. Antibiotics are commonly used in chicken farming to promote growth, but overuse of antibiotics is creating bacteria that are resistant to these drugs, which is a major public health concern. Finding safe, natural alternatives like these acids could help reduce antibiotic use while keeping chickens healthy and productive.

The study used a reasonable sample size (360 chicks) and divided them into multiple smaller groups to reduce the chance of random variation affecting results. The researchers measured multiple health markers rather than just one outcome, which gives a more complete picture. However, this study was conducted in a controlled laboratory setting with young chicks, not in real farm conditions. Results from controlled studies don’t always translate perfectly to real-world farming situations. The study also didn’t compare these acids directly to antibiotics, so we can’t say definitively that they’re better alternatives yet.

What the Results Show

Chickens receiving the combination of both acids (formic and citric) showed the best growth rates and most efficient feed conversion compared to all other groups. This means they gained more weight while eating less feed, which is important for farmers because feed is expensive. All three acid-treated groups performed significantly better than the control group with no added acids.

The chickens receiving acids had higher levels of antioxidant enzymes in their blood. Antioxidants are like bodyguards for cells—they protect them from damage. Higher antioxidant levels suggest the treated chickens had better protection against cellular damage and stress.

When the researchers tested the chickens’ immune response to three common chicken diseases (avian influenza H5, avian influenza H9, and Newcastle disease), the chickens that received the acid combination showed stronger immune responses. This means their bodies were better prepared to fight off these diseases.

The chickens that received formic acid had higher populations of beneficial bacteria called Lactobacillus in their digestive systems compared to the control group. These good bacteria help with digestion and overall gut health.

Blood tests showed that liver and kidney function markers (creatinine, AST, and ALT) remained normal in all groups, suggesting the acids didn’t harm these organs. Chickens receiving formic acid showed slightly elevated thyroid hormone levels, but these remained within the normal healthy range, so this wasn’t a concern. These findings suggest the acids are safe and don’t cause harmful side effects at the doses tested.

Previous research has shown that organic acids can help improve chicken growth and health, but this study is notable because it tested a combination of two different acids rather than just one. The combination approach appears to work better than either acid alone, suggesting that the two acids may work together in complementary ways. The findings align with existing research showing that organic acids can improve gut health and immune function in poultry.

This study was conducted in a controlled laboratory environment with young chicks, not in actual farm settings where conditions are messier and more variable. Results from controlled studies don’t always work the same way on real farms. The study didn’t directly compare these acids to antibiotics, so we can’t say for certain they’re better alternatives. The study also didn’t follow the chickens all the way to market weight or measure meat quality, so we don’t know if these benefits continue as chickens grow older. Additionally, the study was relatively short-term, and long-term effects weren’t evaluated.

The Bottom Line

Based on this research, there is moderate evidence that adding a combination of formic and citric acids to chicken feed may improve growth, immune function, and gut health. However, farmers should wait for additional studies in real farm conditions before making major changes. If you’re interested in supporting more sustainable chicken farming, look for producers who are exploring natural growth promoters as alternatives to antibiotics. For consumers, this research suggests potential future improvements in chicken quality and safety, though benefits may take several years to reach the market.

Poultry farmers and the agricultural industry should care most about this research, as it offers a potential solution to reduce antibiotic use while maintaining productivity. Consumers concerned about antibiotic resistance and food safety should care because reducing antibiotic use in farming is important for public health. People interested in sustainable agriculture and animal welfare may also find this relevant. However, individual consumers don’t need to change their behavior based on this single study—more research is needed first.

If these findings are confirmed in real farm settings and adopted by the poultry industry, it could take 2-5 years before these practices become widespread. Consumers might start seeing benefits in terms of chicken quality and reduced antibiotic residues in meat within 3-7 years if the industry adopts these methods. Individual health benefits would likely be subtle and long-term rather than immediate.

Want to Apply This Research?

  • If you raise backyard chickens, track weekly weight gain and feed consumption for each group if you experiment with acid supplementation. Record the ratio of feed consumed to weight gained (feed conversion ratio) to measure efficiency. Also note any changes in egg production, feather quality, or visible health indicators.
  • For backyard chicken keepers interested in experimenting: Start by adding small amounts of food-grade citric acid or formic acid to your chicken feed according to veterinary guidance. Begin with one group of chickens while keeping a control group on regular feed. Document changes in growth, health, and behavior over 4-6 weeks.
  • Establish a baseline of your chickens’ current health and growth metrics. If implementing acid supplementation, measure weekly weight gain, feed consumption, egg production (if applicable), and observe for any behavioral changes or health issues. Compare treated and control groups monthly. Keep detailed records to identify patterns and determine if the acids are providing benefits in your specific situation.

This research was conducted on young broiler chicks in controlled laboratory conditions and has not yet been tested in real farm environments. Results may not apply to all chicken breeds, ages, or farming conditions. Before making changes to chicken feed or farming practices, consult with a veterinarian or poultry nutrition specialist. This study does not replace professional veterinary advice. If you raise chickens, always follow local regulations and consult experts before adding supplements to feed. This information is for educational purposes and should not be considered medical or veterinary advice for your specific situation.