Research shows that laying hens fed a diet with 2,688 calories of energy per kilogram, 17% protein, and 0.9% lysine produce significantly larger eggs and more total egg mass daily. According to Gram Research analysis of this 12-week study with 450 hens, higher energy and protein levels increased egg weight and improved internal egg quality, while higher lysine boosted both egg size and daily production. These optimal nutrient combinations work together to maximize egg production during peak laying periods.
Researchers tested different combinations of nutrients in chicken feed to find the perfect recipe for healthy eggs. They studied 450 laying hens for 12 weeks, adjusting three key ingredients: energy content, protein, and an amino acid called lysine. According to Gram Research analysis, hens eating feed with higher energy and protein levels produced larger eggs with stronger shells and better quality. The study found that the ideal diet included 2,688 calories of energy per kilogram of feed, 17% protein, and 0.9% lysine. These findings help farmers create better chicken diets to improve egg production and quality.
Key Statistics
A 2026 study of 450 Jingfen laying hens found that hens fed the highest energy diet (2,700 kcal/kg) produced significantly larger eggs and greater daily egg mass compared to hens fed lower energy diets (2,500 kcal/kg).
Research on 450 laying hens showed that hens fed 17% dietary protein produced eggs with significantly better internal quality (higher Haugh unit scores) compared to hens fed medium protein levels (16%).
A 12-week trial with 450 hens demonstrated that the highest lysine level (0.9%) resulted in significantly greater egg weight and daily egg production compared to lower lysine diets (0.7%).
Response surface methodology analysis of 450 hens identified optimal dietary levels of 2,688 kcal/kg energy, 17% crude protein, and 0.9% lysine for maximizing production performance in Jingfen laying hens.
The Quick Take
- What they studied: How different levels of energy, protein, and a nutrient called lysine in chicken feed affect egg production and egg quality in laying hens.
- Who participated: 450 twenty-week-old Jingfen laying hens (a Chinese chicken breed) divided into 15 groups, with 10 hens per group living in cages. The study lasted 12 weeks during the hens’ peak egg-laying period.
- Key finding: Hens fed diets with higher energy (2,688 kcal/kg), higher protein (17%), and higher lysine (0.9%) produced larger eggs with better quality. The optimal diet increased egg weight and daily egg production compared to lower nutrient levels.
- What it means for you: If you raise chickens or buy eggs, understanding proper chicken nutrition can lead to better egg quality and more consistent production. However, these results are specific to one chicken breed and may not apply to all egg-laying hens.
The Research Details
Scientists designed an experiment using something called response surface methodology, which is like testing multiple recipes at once to find the best combination. They created 15 different chicken feed formulas by mixing three nutrients at different levels: energy (2,500, 2,600, or 2,700 calories per kilogram), protein (15%, 16%, or 17%), and lysine (0.7%, 0.8%, or 0.9%). Each formula was fed to three separate groups of hens, with 10 hens per group living together in cages.
The researchers measured many things over 12 weeks: how many eggs the hens laid, how big the eggs were, how strong the shells were, and even checked the hens’ blood for signs of health. They also looked inside the hens’ reproductive organs to see how well they were functioning. This detailed approach helped them understand exactly how each nutrient affected egg production and quality.
The response surface methodology is powerful because it tests many combinations at once and uses math to find the sweet spot—the exact nutrient levels that work best together. This is more efficient than testing one nutrient at a time.
Finding the right chicken diet is important for farmers who want healthy, productive hens. Better nutrition means more eggs, larger eggs, and eggs with stronger shells that don’t break easily. This research helps farmers save money by using exactly the right amount of expensive nutrients instead of guessing or using too much.
This study is well-designed with multiple replicate groups (each diet tested three times), a reasonable sample size (450 hens), and careful measurement of many different outcomes. The researchers used a sophisticated statistical method (response surface methodology) to find optimal nutrient combinations. However, results are specific to one chicken breed (Jingfen) and may not apply to other breeds. The study was conducted in controlled conditions, which is good for finding cause-and-effect but may differ from real farm conditions.
What the Results Show
Hens eating feed with higher energy content produced significantly larger eggs and laid more eggs overall. When energy increased from 2,500 to 2,700 kcal/kg, egg weight and daily egg production both improved. The eggshell also became proportionally thicker with higher energy diets, which is important because stronger shells mean fewer broken eggs.
Protein level had a major impact on egg quality. Hens fed the highest protein diet (17%) produced eggs with better internal quality, measured by something called Haugh unit—essentially a score for how firm and healthy the egg white is. Higher protein also affected the hens’ blood chemistry, increasing certain fat and protein markers.
Lysine, an amino acid that’s a building block for proteins, significantly affected both egg size and production. Hens receiving the highest lysine level (0.9%) laid larger eggs and produced more total egg mass daily compared to hens on lower lysine diets. The hens’ blood protein levels were also higher with increased lysine.
When researchers combined all the data using mathematical analysis, they determined the optimal recipe: 2,688 calories of energy per kilogram of feed, 17% protein, and 0.9% lysine. This combination maximized egg production while maintaining good egg quality.
The study revealed important details about hen reproduction. Hens fed medium and high-energy diets had larger ovaries (the reproductive organs) and more developing egg follicles compared to hens on low-energy diets. This suggests that energy is crucial for supporting the hen’s reproductive system. Hens on low-protein diets had lower levels of triglycerides (a type of fat), uric acid, and LDL cholesterol in their blood, which might seem positive but could indicate insufficient nutrition for optimal egg production.
This research builds on decades of poultry nutrition studies by using a more sophisticated approach to find exact nutrient combinations. Previous studies often tested nutrients separately, but this research shows that nutrients work together—the best energy level depends on the protein and lysine levels used. The findings align with general knowledge that laying hens need adequate energy and protein, but provide specific numbers for the Jingfen breed. The optimal protein level (17%) is at the higher end of typical recommendations, suggesting this breed may have higher protein needs than some other laying hen breeds.
This study was conducted only with Jingfen laying hens, a Chinese breed, so results may not apply to other chicken breeds commonly raised in other countries. The hens were housed in cages in controlled conditions, which differs from free-range or barn systems where hens might have different nutritional needs. The study lasted only 12 weeks during peak laying, so we don’t know if these nutrient levels remain optimal throughout the hen’s entire laying life. The research doesn’t address cost-effectiveness—while 17% protein is optimal for production, it may be more expensive than lower protein feeds. Finally, the study focused on one specific time period (peak laying at 20+ weeks old) and may not apply to younger or older hens.
The Bottom Line
For farmers raising Jingfen laying hens: Feed a diet containing approximately 2,688 kcal/kg of energy, 17% crude protein, and 0.9% lysine to maximize egg production and quality. This recommendation has strong evidence from this controlled study (high confidence). For other chicken breeds, consult breed-specific nutrition guidelines, as needs may differ. Consider working with a poultry nutritionist to balance optimal nutrition with feed costs, as higher protein feeds are more expensive.
Commercial and backyard chicken farmers raising Jingfen laying hens should pay attention to these findings. Poultry nutritionists and feed manufacturers can use this data to formulate better feeds for this breed. Egg producers focused on quality should consider these nutrient levels. However, if you raise different chicken breeds, these specific numbers may not apply—consult breed-specific guidelines instead. This research is less relevant for people who don’t raise chickens.
Changes in egg production typically appear within 1-2 weeks of diet changes in laying hens, as they adjust to new nutrition. Improvements in egg quality (shell strength, internal quality) may take 2-4 weeks to fully manifest. Maximum benefits should be visible within 4-6 weeks on the optimal diet.
Frequently Asked Questions
What is the best diet for laying hens to produce more eggs?
Feed containing 2,688 calories per kilogram of energy, 17% protein, and 0.9% lysine maximizes egg production in laying hens. This combination significantly increases both egg size and daily production compared to lower nutrient levels.
How does protein affect chicken egg quality?
Higher dietary protein (17%) improves internal egg quality, making the egg white firmer and more stable. Protein also supports the hen’s reproductive system and overall health, though excessive protein increases certain blood fat markers.
Why is lysine important for laying hens?
Lysine is an amino acid that hens need to build proteins for egg production. Higher lysine levels (0.9%) significantly increase both egg weight and the total amount of eggs produced daily, making it essential for optimal laying performance.
How long does it take to see improvements from better chicken feed?
Egg production typically increases within 1-2 weeks of switching to optimal nutrition. Improvements in egg quality and shell strength take 2-4 weeks, with maximum benefits visible within 4-6 weeks on the improved diet.
Does this chicken nutrition research apply to all chicken breeds?
These specific nutrient levels were tested only on Jingfen laying hens, a Chinese breed. Other chicken breeds may have different nutritional requirements, so consult breed-specific guidelines or a poultry nutritionist for your particular birds.
Want to Apply This Research?
- If managing a chicken flock, track daily egg production numbers and measure egg weight weekly. Record the exact feed formulation being used (energy, protein, and lysine percentages) and correlate with egg output. Monitor for broken or cracked eggs daily as an indicator of shell quality.
- Switch to a feed formulation matching the optimal levels (2,688 kcal/kg energy, 17% protein, 0.9% lysine) and track changes in egg production and quality over the following 4-6 weeks. Document baseline metrics before switching, then measure improvements in egg count, size, and shell strength.
- Establish a weekly tracking system recording: total eggs laid, average egg weight, percentage of broken eggs, and feed consumption. Compare these metrics before and after diet optimization. If using the app, set weekly reminders to weigh eggs and count production, creating a visual trend showing improvement over 8-12 weeks.
This research applies specifically to Jingfen laying hens during peak laying periods and may not apply to other chicken breeds, ages, or production systems. Consult with a poultry veterinarian or nutritionist before making significant changes to your flock’s diet, as individual birds and farm conditions vary. This information is for educational purposes and should not replace professional agricultural or veterinary advice. Feed costs and availability may affect the practical application of these optimal nutrient levels.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.