Scientists studied 650 chickens to understand why some birds can eat less food while staying just as healthy and productive as others. By looking at the chickens’ genes and blood chemicals, researchers found that the efficient eaters had better digestion, less inflammation in their bodies, and different ways of controlling their appetite. These findings could help farmers breed chickens that need less food to grow, which saves money and is better for the environment. The study identified specific genes and blood markers that could help farmers select the most efficient chickens for breeding.

The Quick Take

  • What they studied: Why some chickens can eat less food while staying healthy and productive, compared to chickens that need to eat more to do the same job
  • Who participated: 650 female Tianchang Sanhuang chickens (a Chinese breed) that were all about the same weight at 36 weeks old. Researchers focused closely on 16 chickens total—8 that ate efficiently and 8 that didn’t
  • Key finding: Chickens that ate less food had better digestion, less body inflammation, healthier blood fat levels, and different genes controlling how much they wanted to eat. They stayed just as productive while eating significantly less
  • What it means for you: While this research is about chickens, the findings suggest that efficient eating is connected to good digestion and low inflammation. For farmers, this could lead to breeding chickens that need less feed, saving money and reducing environmental impact. The results may eventually help scientists understand similar efficiency patterns in other animals

The Research Details

Researchers started with 650 chickens and measured how much each one ate and how well they converted that food into body weight and eggs. They divided the chickens into two groups: those that ate less than expected for their size (efficient eaters) and those that ate more than expected (less efficient eaters). Each group had about 160 chickens.

For a closer look, they selected 8 chickens from each group and tested their blood, measured their intestines, and looked at how well their bodies absorbed nutrients. They also took samples from the chickens’ small intestines and blood to study their genes and chemical makeup using advanced laboratory techniques called RNA sequencing and mass spectrometry.

This approach combined two types of analysis: one that looks at which genes are turned on or off, and another that measures all the different chemicals in the blood. By combining both approaches, the researchers could get a complete picture of why some chickens were more efficient eaters.

This research method is important because it doesn’t just look at one thing—it examines the whole system. By studying both genes and blood chemicals together, scientists can understand not just that efficient chickens eat less, but WHY they do it. This gives farmers actual targets they can use to breed better chickens, rather than just knowing that some chickens are more efficient

The study used a large number of chickens (650), which makes the results more reliable. The researchers used modern scientific tools to measure genes and blood chemicals precisely. However, the detailed analysis only included 8 chickens per group, which is a smaller number. The study was done in a controlled setting with one chicken breed, so results might be different in other breeds or in different environments. The research was published in a respected scientific journal focused on poultry science

What the Results Show

The efficient eaters (chickens that needed less food) had noticeably lower levels of fat in their blood, including triglycerides, cholesterol, and LDL cholesterol—the kind of fat that can be unhealthy. They also had lower levels of a harmful chemical called malondialdehyde, which shows their bodies had less inflammation and stress.

When researchers looked at the chickens’ intestines, they found that the efficient eaters had better intestinal structure and stronger intestinal barriers. This means their guts were better at absorbing nutrients from food and preventing harmful substances from entering their bloodstream. Their muscles also showed different characteristics—the breast meat was redder (suggesting better blood flow), though the leg muscles lost more moisture when stored.

The gene analysis found 237 genes that worked differently between the two groups. These genes were involved in breaking down food, managing energy, and controlling appetite. The blood chemical analysis found 101 different chemicals, with the biggest differences in how the chickens’ bodies handled proteins and fats.

The researchers identified eight specific genes that appeared to be the main controllers of feed efficiency: ACSM5, AHSG, CTRB1, PLA2G1B, AMY2A, CPA1, CCKAR, and five blood chemicals including taurine and uridine that could serve as markers to identify efficient eaters

The efficient eaters had lower daily food intake overall, which was expected, but they also had better feed conversion ratios—meaning they got more production (eggs or growth) from each bite of food. Their blood showed signs of better overall health with lower inflammation markers. The intestinal measurements showed that efficient eaters had better nutrient absorption capacity, suggesting their digestive systems were working more effectively. These chickens also appeared to have better appetite control, eating only what they needed rather than overeating

Previous research has suggested that feed efficiency in animals is related to digestion and metabolism, but this study provides specific genes and blood markers that hadn’t been clearly identified before. The finding that efficient eaters have lower inflammation and better intestinal health aligns with recent research in other animals showing that gut health is crucial for efficient nutrient use. This study goes further by identifying the exact genes and chemicals involved, making it more useful for practical breeding programs

The detailed analysis only included 8 chickens per group, which is a small number for drawing very strong conclusions. The study was done only with one chicken breed in a controlled farm setting, so the results might not apply to other breeds or chickens raised in different conditions. The research was done at one point in time, so it doesn’t show whether these differences stay the same as chickens age. The study doesn’t prove that the identified genes actually CAUSE better efficiency—it only shows they’re associated with it. More research would be needed to confirm these findings and test whether selecting for these genes actually improves efficiency in real farming situations

The Bottom Line

For chicken farmers: This research suggests that selecting breeding chickens based on these eight genes and five blood markers could improve feed efficiency. However, farmers should wait for additional research before making major breeding decisions, as this is early-stage research. The findings are most reliable for the Tianchang Sanhuang breed studied here. For scientists: This research provides a strong foundation for developing genetic tests to identify efficient eaters and for understanding the biological reasons why some animals are more efficient. The combination of gene and blood chemical analysis proved valuable and should be used in future studies

Chicken farmers and breeding programs should pay attention to these findings, especially those raising Tianchang Sanhuang chickens or similar Asian chicken breeds. Large-scale poultry operations could benefit from using these genetic markers in breeding programs. Environmental advocates should care because more efficient chickens mean less feed needed, which reduces the environmental impact of chicken farming. Scientists studying animal nutrition and genetics should use this research as a foundation for further work. General consumers might eventually benefit through more sustainable and affordable chicken production

If farmers began selecting chickens based on these markers today, they would likely see measurable improvements in feed efficiency within 2-3 breeding generations (roughly 1-2 years for chickens). However, the research is still new, and it would take 3-5 years of additional testing to confirm these results work in real farming conditions. Full implementation in commercial breeding programs would likely take 5-10 years

Want to Apply This Research?

  • For farmers using a nutrition app: Track feed intake per chicken and feed conversion ratio (pounds of feed needed per pound of eggs or meat produced) weekly. Compare these numbers to the breed average to identify which individual chickens are most efficient. Note any changes when implementing new feeding strategies
  • Farmers could use an app to record which chickens in their flock show signs of the efficient eater profile: lower daily food intake, good production levels, and healthy blood work results. The app could flag chickens that match the genetic markers identified in this study (if genetic testing becomes available) and recommend them for breeding programs
  • Set up monthly tracking of feed efficiency metrics for your flock. Create alerts if individual chickens’ feed conversion ratios drop below breed standards, which might indicate health problems. Track trends over breeding seasons to see if selecting for efficiency markers improves your overall flock performance. Keep records of which birds you select for breeding and monitor their offspring’s efficiency in the next generation

This research is specific to chickens and should not be applied to human nutrition or health without additional research. While the findings are scientifically sound, they represent early-stage research that may need confirmation through additional studies. Farmers should consult with poultry veterinarians and breeding specialists before making major changes to breeding programs based on this research. The genetic markers identified are associated with feed efficiency but do not guarantee improved performance in all conditions or breeds. Individual results may vary based on farm management, environment, and other factors not studied here. This summary is for informational purposes and should not replace professional agricultural or veterinary advice.