Phase Feeding for Laying Hens: Adjusting Nutrition by Age

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-14

Key Takeaways

• Phase feeding adjusts laying hen nutrition by age, optimizing protein, calcium, phosphorus, and energy levels to match physiological demands, thereby improving feed efficiency and bird health.
• The pre-lay diet (weeks 16-18) with 2-2.5% calcium prepares hens for shell production by building medullary bone reserves, preventing kidney damage from abrupt high calcium introduction.
• Peak production (weeks 25-35) requires the highest nutrient density, typically 17-18% protein and 3.5-4% calcium, to support maximum egg output (90-95% hen-day production).
• Post-peak diets (after week 40-45) reduce protein to 15-16% and energy to prevent excess fat deposition, mitigating risks like fatty liver hemorrhagic syndrome.
• Late-lay diets (after week 60) prioritize eggshell quality with elevated calcium (4-4.5%) and often incorporate larger calcium particles for slow release, addressing age-related declines in calcium absorption.
• Gradual feed transitions over 5-7 days by blending old and new rations are crucial to prevent digestive upset and production drops, with continuous monitoring of feed intake, egg production, and body weight essential for fine-tuning.

Getting the right feed in front of your laying hens at the right time is one of the highest-impact decisions you make each year. Feed represents 60 to 70 percent of the cost of producing a dozen eggs, so every pound you feed must support either egg production, body maintenance, or future laying performance. Phase feeding is the practice of adjusting the protein, calcium, phosphorus, and energy levels in the diet as the flock ages, matching the feed to the bird's changing physiological needs.

This guide covers the full timeline of layer nutrition, from the pre-lay diet through peak production and into the post-peak period. It explains why nutrient needs change, how to transition feeds without disrupting egg production, how to read flock signals that your current feed is wrong, and how to monitor results with simple records. The guidance is written for small to mid-scale commercial egg producers, farm managers, and serious hobby farmers with flocks of 50 birds or more. If you sell eggs commercially, the same principles apply whether you run a 200-bird pastured flock or a 10,000-bird barn operation.

At a Glance

• Pre-lay diet (weeks 16 to 18): Feed a layer ration with about 2 percent calcium to prepare the hen for shell production without overloading her system.
• Start the full layer ration (3.5 to 4 percent calcium) at first egg or at 18 weeks, whichever comes first.
• Peak production (weeks 25 to 35): Hens need the highest protein level, typically 17 to 18 percent, and the highest energy intake of the laying cycle.
• Post-peak (after week 40 to 45): Reduce protein to 15 to 16 percent and adjust feed intake to prevent excess body fat.
• Late lay (after week 60): Maintain calcium at the high end, reduce energy, and consider a separate diet if eggshell quality declines.
• Water intake equals feed intake in hot weather, so never restrict water to control feed consumption.
• Change feeds gradually over 5 to 7 days by blending old and new rations.
• Keep records of feed consumed, eggs produced, egg weight, and body weight to fine-tune your program.

Why Layer Nutrient Needs Change With Age

A laying hen is not a static machine. Her body changes significantly from the day she starts laying to the day she is sold or molted. The nutrients she needs at 20 weeks are different from what she needs at 50 weeks, and feeding her the same ration the whole time costs you money and can hurt her health.

The Physiology of Early Lay

When a pullet starts laying, she is still growing. A Leghorn-type hen will gain about 0.5 to 0.75 pounds of body weight between 18 and 32 weeks of age, and that growth requires protein and energy beyond what she needs for egg production. Her skeleton is also still developing, particularly the medullary bone in her legs and wings, which serves as a calcium reserve for shell formation. If she does not get enough calcium and phosphorus during this period, she will draw calcium from her bones, and you will see poor shell quality later in the laying cycle.

The first few eggs a pullet lays are often small, misshapen, or have thin shells. This is normal. Her reproductive tract is still maturing, and her calcium metabolism is adjusting to the enormous demand of producing a shell every 24 to 26 hours. The pre-lay diet is designed to ease this transition.

Peak Production and Maximum Demand

Hens reach peak production between 25 and 35 weeks of age, depending on breed and season. At peak, a good commercial flock will lay at 90 to 95 percent, meaning 9 out of 10 hens lay an egg on a given day. Each egg contains about 6 grams of protein, mostly in the albumen, plus about 2 grams of calcium in the shell. Multiply that by 100 hens and you are looking at 600 grams of protein and 200 grams of calcium demanded every single day just for eggs.

During this period, the hen's digestive system is working at maximum capacity. She cannot eat unlimited feed, so the diet must be dense enough in protein, energy, calcium, and phosphorus to meet her needs within her physical feed intake limit. This is why peak diets are the richest of the laying cycle.

The Post-Peak Decline

After peak, egg production gradually declines by about 0.5 to 1 percent per week. A flock that laid at 92 percent at 30 weeks might be at 85 percent by 40 weeks and 75 percent by 50 weeks. The hen's protein requirement drops because she is producing fewer eggs. Her energy requirement also drops because she is no longer gaining weight as rapidly. If you keep feeding the peak diet, she will consume more energy than she needs and put on fat.

Excess fat in laying hens is a serious problem. Fat hens are more prone to fatty liver hemorrhagic syndrome, a condition where the liver accumulates fat and can rupture, causing sudden death. Fat hens also lay fewer eggs, have poorer shell quality, and are more difficult to handle at processing. The post-peak diet is designed to prevent this.

Late Lay and Shell Quality

In the final phase of the laying cycle, after about week 60, eggshell quality becomes the primary nutritional concern. As hens age, their ability to absorb calcium from the gut declines, and their bones become less efficient at releasing calcium. The shell gland also becomes less efficient at depositing calcium onto the egg. The result is thinner shells, more cracked eggs, and more eggs with rough or pimpled shells.

The late-lay diet keeps calcium high, often at 4 to 4.5 percent, and reduces protein and energy further. Some producers also add extra vitamin D3, which helps calcium absorption, and adjust the particle size of the calcium source to include larger particles that release calcium slowly through the night when the shell is being formed.

The Pre-Lay Diet: Weeks 16 to 18

The pre-lay diet is the bridge between the grower ration and the full layer ration. It is often overlooked, but it plays a critical role in preparing the pullet for the demands of egg production.

What the Pre-Lay Diet Contains

A typical pre-lay diet contains about 16 to 17 percent protein and 2 to 2.5 percent calcium. The protein level is similar to a late grower diet, but the calcium is elevated to start building medullary bone. The phosphorus level is usually around 0.4 to 0.45 percent available phosphorus.

The key difference from the grower diet is the calcium level. A grower diet typically contains 0.8 to 1 percent calcium, which is enough for bone development but not for shell formation. Jumping straight from 1 percent to 4 percent calcium at first egg can cause kidney damage and reduce feed intake at the worst possible time. The pre-lay diet at 2 to 2.5 percent calcium bridges this gap.

When to Start the Pre-Lay Diet

Start the pre-lay diet at 16 weeks of age or when the pullets reach about 95 percent of their expected mature body weight, whichever comes first. For a White Leghorn, that is roughly 2.6 to 2.8 pounds. For a brown egg layer like a Rhode Island Red or Hy-Line Brown, that is roughly 3.4 to 3.6 pounds.

If you are raising mixed breeds or have uneven pullets, base the decision on the average body weight of the flock. Do not wait for the first egg. The medullary bone needs to be built before the first shell is formed, and that takes about two weeks of elevated calcium intake.

Feeding the Pre-Lay Diet

Feed the pre-lay diet free choice from 16 weeks until the flock reaches about 5 percent egg production, which is typically around 18 to 19 weeks of age. At that point, switch to the full layer ration.

Some producers skip the pre-lay diet entirely and move pullets straight from grower to layer ration at first egg. This works, but it often causes a temporary dip in feed intake and a few days of poor shell quality. The pre-lay diet smooths this transition and is worth the extra handling if you have the facilities to store a third feed.

Common Mistakes With the Pre-Lay Diet

The most common mistake is starting the pre-lay diet too early. If you feed 2.5 percent calcium to pullets at 12 weeks of age, you can cause kidney damage and reduce growth. The pullet's calcium metabolism is not ready for that load until about 16 weeks.

Another mistake is feeding the pre-lay diet too long. Once the flock reaches 5 percent production, the calcium level in the pre-lay diet is too low to support shell formation. Leaving pullets on the pre-lay diet past 20 weeks will result in thin shells and increased cracked eggs.

The Peak Layer Diet: Weeks 18 to 40

The peak layer diet is the richest ration of the entire laying cycle. It is designed to support maximum egg production, continued body growth, and the beginning of the hen's calcium storage for later in the cycle.

Protein and Amino Acids

The peak layer diet typically contains 17 to 18 percent crude protein. The exact level depends on the breed, the ambient temperature, and the feed intake of the flock. The critical amino acids are methionine and lysine. Methionine is usually the first limiting amino acid in layer diets, meaning it is the one that runs out first and limits egg production. A typical peak diet contains 0.38 to 0.42 percent methionine and 0.75 to 0.85 percent lysine.

If you are buying a commercial layer feed, the tag will list the protein percentage, but it may not list the amino acid levels. Ask your feed supplier for the amino acid profile. A feed with 18 percent protein but low methionine will not perform as well as a feed with 17 percent protein and adequate methionine.

Calcium and Phosphorus

The peak layer diet contains 3.5 to 4 percent calcium. The exact level depends on the expected feed intake. If your hens eat 0.25 pounds of feed per day, a 4 percent calcium diet provides about 4.5 grams of calcium per hen per day, which is enough for a shell plus some bone storage. If your hens eat only 0.2 pounds per day, you need a higher calcium percentage to deliver the same amount.

Available phosphorus is typically 0.4 to 0.45 percent in the peak diet. Phosphorus works with calcium to build medullary bone and is also involved in energy metabolism. Too little phosphorus reduces egg production. Too much phosphorus can interfere with calcium absorption, so do not exceed 0.5 percent available phosphorus.

Energy

The energy content of the peak diet is typically 2,800 to 2,950 kcal of metabolizable energy per pound (about 1,250 to 1,300 kcal per pound on an as-fed basis, depending on how your feed supplier labels it). Hens eat to meet their energy requirement, so the energy density of the feed controls how much they consume. A higher energy feed means lower feed intake, which means you need a higher concentration of protein, calcium, and phosphorus to deliver the same daily amounts.

In hot weather, hens eat less, so you may need to increase the energy density of the feed to maintain intake. In cold weather, hens eat more, so you can reduce the energy density slightly.

Feeding Management During Peak

Feed the peak diet free choice from 18 weeks until about week 40, or until egg production drops below 85 percent. Most commercial flocks stay on the peak diet until production falls to 85 to 88 percent, which typically happens around week 40 to 45.

Monitor feed intake closely during this period. A healthy peak flock should eat about 0.22 to 0.27 pounds per hen per day, depending on breed, temperature, and energy density. If feed intake drops suddenly, check for disease, heat stress, or a feed quality problem. A drop in feed intake of more than 10 percent for more than two days will show up as a drop in egg production about 7 to 10 days later.

The Post-Peak Diet: Weeks 40 to 60

The post-peak diet is the first step down from the richest ration. It is designed to match the hen's declining protein and energy needs while maintaining calcium intake for shell quality.

When to Transition

Transition to the post-peak diet when the flock's egg production drops to about 85 percent. For a typical flock, this happens around week 40 to 45, but it varies by breed, season, and management. Use your production records to make the decision, not the calendar alone.

If you are feeding a single diet all the way through lay, you can skip this transition and simply reduce the feed allocation or adjust the energy density. But if you have the ability to change rations, the post-peak diet will save you money on protein and reduce the risk of fatty liver.

What Changes in the Post-Peak Diet

The post-peak diet typically contains 15.5 to 16.5 percent protein, down from 17 to 18 percent. Methionine drops to about 0.36 to 0.38 percent, and lysine drops to about 0.68 to 0.72 percent. Calcium stays at 3.8 to 4.2 percent, and available phosphorus drops slightly to 0.38 to 0.42 percent.

Energy is often reduced by 50 to 100 kcal per pound to account for the hen's lower energy requirement. This helps prevent excess fat deposition. However, be careful not to reduce energy too much in cold weather, as the hens will simply eat more feed to compensate, which can be more expensive than feeding a slightly higher energy diet.

How to Transition

Change feeds gradually over 5 to 7 days. On day one, mix 80 percent old feed with 20 percent new feed. On day two, 60 percent old with 40 percent new. Continue until you are feeding 100 percent new feed. This gradual transition prevents digestive upset and gives the hens time to adjust their feed intake.

Do not change the feed and the lighting program at the same time. If you are reducing day length or changing the light intensity, do that first, wait a week, then change the feed. Too many changes at once makes it difficult to identify the cause of any production dip.

Monitoring the Transition

Watch egg production and egg weight for two weeks after the transition. A small dip in production of 1 to 2 percent is normal as the hens adjust to the lower protein level. If production drops more than 3 percent, or if egg weight drops noticeably, the post-peak diet may be too low in protein or methionine for your flock. Move back to the peak diet and try again in two weeks.

Also watch body weight. Weigh a sample of 20 to 30 hens at the transition and again four weeks later. Hens should maintain or slightly increase body weight during this period. If they lose weight, the diet is too low in energy or protein. If they gain more than 0.1 pound in four weeks, the diet is too high in energy.

The Late-Lay Diet: Week 60 to Depletion

The late-lay diet is the final phase of the feeding program. It is designed primarily to maintain shell quality and prevent excess fat, not to maximize egg numbers.

When to Transition

Transition to the late-lay diet when egg production drops below 75 percent or when you start seeing a noticeable increase in cracked eggs, typically around week 60 to 65. If you plan to sell the flock at 70 weeks, you may not need a separate late-lay diet. If you plan to keep hens to 90 weeks or longer, the late-lay diet becomes important.

What Changes in the Late-Lay Diet

The late-lay diet contains 14.5 to 15.5 percent protein, down from the post-peak level. Methionine drops to about 0.34 to 0.36 percent, and lysine drops to about 0.62 to 0.66 percent. Calcium stays at 4 to 4.5 percent, which is the highest of the entire cycle. Available phosphorus drops to 0.35 to 0.38 percent.

The late-lay diet often includes larger particles of calcium, such as limestone or oyster shell with a particle size of 2 to 4 millimeters. Large particles stay in the gizzard longer and release calcium slowly through the night, which is when the shell is being formed. If you are using a complete feed, ask your supplier if it contains large-particle calcium. If you are mixing your own feed, add 1 to 1.5 percent large-particle calcium in place of some of the fine limestone.

Special Considerations for Late-Lay Hens

Older hens are more sensitive to heat stress, and their feed intake drops more in hot weather. If you are feeding a late-lay flock through summer, consider increasing the energy density of the feed to maintain intake. You may also need to increase the calcium to 4.5 percent to compensate for reduced intake.

Older hens also have weaker immune systems and are more susceptible to disease. Keep the feed fresh, clean the feeders regularly, and watch for signs of illness. A drop in feed intake in a late-lay flock is a warning sign that should not be ignored.

The Decision to Molt or Deplete

If you are considering a forced molt, the feeding program changes entirely. A molt diet is very low in protein and calcium, often 12 to 13 percent protein and 1 percent calcium, and is fed for 2 to 4 weeks to stop egg production and allow the reproductive tract to rest. After the molt, the hen goes back on a peak-type diet. Consult your veterinarian or extension agent before starting a molt program, as molt practices vary by region and may be regulated in your area.

If you are depleting the flock, meaning sending them to processing, the late-lay diet is the last ration they will receive. There is no need to adjust the diet for the final week, as the withdrawal period for any medications or feed additives should already be managed according to the product label.

How to Transition Between Layer Feeds

Changing feeds is a routine part of layer management, but it needs to be done carefully to avoid production losses. This section covers the step-by-step process for any feed transition.

Step 1: Calculate How Much Feed You Need

Before you start the transition, calculate how much feed you will need to complete the changeover. For a flock of 1,000 hens eating 0.25 pounds per day, the daily feed consumption is 250 pounds. Over 7 days, that is 1,750 pounds. You will need about 1,400 pounds of the old feed and 350 pounds of the new feed, assuming you are blending at 80/20, 60/40, 40/60, 20/80, and 0/100 over five days.

Do not run out of feed during the transition. If the hens run out of feed for even a few hours, egg production will drop and may not recover fully for weeks.

Step 2: Clean the Feed System

Clean the feed bins, augers, and feeders before starting the transition. Old feed that has been sitting in the corners can harbor mold, insects, or stale fat, which will contaminate the new feed. Empty the bins completely, sweep out any residue, and inspect for signs of moisture or pests.

If you use tube feeders or troughs, empty them and give them a quick cleaning. This is also a good time to check that all feeders are working properly and that no feed is being wasted.

Step 3: Blend the Feeds

Follow this blending schedule for a 7-day transition:

• Days 1 and 2: 75 percent old feed, 25 percent new feed
• Days 3 and 4: 50 percent old feed, 50 percent new feed
• Days 5 and 6: 25 percent old feed, 75 percent new feed
• Day 7 onward: 100 percent new feed

If you have a single feed bin, you can do this by emptying the bin, adding the new feed, and then adding the old feed on top, allowing the hens to mix it as they eat. This is less precise but works for small flocks. If you have multiple bins, you can blend in the auger system by running both feeds simultaneously.

For very small flocks, you can mix the feeds in a clean garbage can or wheelbarrow. Just make sure the mix is uniform before you put it in the feeders.

Step 4: Monitor the Flock

Watch the flock closely for the first week after the transition. Look for changes in feed intake, water intake, egg production, egg quality, and behavior. A small dip in production of 1 to 2 percent is normal. A larger drop, loose droppings, or reduced activity may indicate that the new feed is not palatable or that the hens are having digestive issues.

Weigh a sample of hens before and after the transition to confirm that body weight is stable. If hens lose weight, the new feed may be too low in energy or protein. If they gain weight rapidly, the new feed may be too high in energy.

Common Mistakes in Layer Phase Feeding

Even experienced producers make mistakes in phase feeding. Here are the most common problems and how to avoid them.

Feeding the Same Ration All Year

The most common mistake is feeding the same layer ration from 18 weeks to depletion. This is convenient, and many small feed mills only offer one layer feed. But it means you are overfeeding protein and energy in the post-peak period, which costs money and increases the risk of fatty liver.

If you cannot get a separate post-peak or late-lay feed from your supplier, you can adjust by limiting feed intake or by adding a low-protein ingredient like oats or wheat bran to dilute the ration. For example, replacing 10 percent of the layer ration with whole oats reduces the protein and energy of the diet. This is not as precise as a formulated post-peak diet, but it is better than feeding the peak diet all year.

Switching Feeds Too Quickly

Changing from the grower diet to the layer diet overnight can cause a sharp drop in feed intake and a temporary halt in egg production. The digestive system needs time to adjust to the higher calcium and protein levels. Always transition over at least 5 days, and 7 days is better.

The same applies to transitions between layer feeds. Do not switch from a peak diet to a post-peak diet in one day. Blend the feeds as described above.

Ignoring Feed Intake

Feed intake is the single most important number to track in a layer flock. It tells you whether the hens are healthy, whether the feed is palatable, and whether the nutrient density is correct. Many producers track egg production carefully but ignore feed intake until there is a problem.

Measure feed intake at least weekly. Weigh the feed you put in the feeders and subtract the feed left over at the end of the week. Divide by the number of hen-days to get the average feed intake per hen per day. Compare this to the expected intake for your breed and age. If intake is more than 10 percent above or below expected, investigate the cause.

Overfeeding Calcium in the Pre-Lay Period

Feeding a full layer ration with 4 percent calcium to pullets before they start laying can cause kidney damage and reduce feed intake. The pullet's kidneys are not ready to excrete that much calcium. Use a pre-lay diet with 2 to 2.5 percent calcium until the flock reaches 5 percent production.

Underfeeding Calcium in Late Lay

As hens age, their calcium absorption efficiency drops. A 70-week-old hen needs more calcium in her diet than a 30-week-old hen to produce the same shell. If you keep the calcium at 3.5 percent through the whole cycle, you will see an increase in cracked eggs and poor shell quality in the late lay period. Increase calcium to 4 to 4.5 percent after week 60.

Not Adjusting for Season

Hens eat more in cold weather and less in hot weather. A diet that is correct in March may be too low in energy in January and too high in energy in July. Adjust the energy density of the diet seasonally, or adjust the feed allocation if you are feeding a fixed amount.

In hot weather, consider feeding during the cooler parts of the day, such as early morning and late evening. This encourages feed intake and reduces heat stress. In extreme heat, you may need to increase the energy density of the feed to maintain intake.

Ignoring Water Quality and Availability

Water is the most important nutrient, and it is often overlooked. Hens need about 2 pounds of water for every pound of feed they consume. If water is restricted, unavailable, or unpalatable, feed intake drops and production suffers.

Check water lines, nipples, and cups daily. Clean waterers regularly, especially in hot weather. If you are using well water, test it for minerals and bacteria at least twice a year. High levels of iron, sulfur, or total dissolved solids can make water unpalatable and reduce intake.

Decision Thresholds: When to Adjust Your Feeding Program

Knowing when to change the feeding program is as important as knowing how to change it. Here are the key thresholds to watch.

Egg Production Thresholds

• Below 5 percent production: Move from pre-lay diet to peak layer diet.
• Production drops to 85 percent: Move from peak diet to post-peak diet.
• Production drops to 75 percent: Move from post-peak diet to late-lay diet.

These thresholds are based on standard commercial breeds. If you are raising a breed with a naturally lower peak, such as some heritage breeds, adjust the thresholds accordingly. The key is to match the diet to the hen's actual production, not to a calendar date.

Egg Weight Thresholds

Egg weight should increase steadily from first egg to about week 35, then stabilize. If egg weight is below the breed standard for the age, the diet may be too low in protein or methionine. Increase protein by 0.5 to 1 percent and check the methionine level.

If egg weight is above the breed standard, you may be overfeeding protein. This is not immediately harmful, but it costs money and can contribute to excessive egg size, which increases the risk of egg breakage and prolapse in older hens.

Body Weight Thresholds

Weigh a sample of 20 to 30 hens every 2 to 4 weeks. The sample should be representative of the flock, so pick hens from different areas of the house. Use a scale that can weigh to the nearest 0.05 pound.

• If hens lose more than 0.1 pound between weighings, increase the energy density of the diet or check for disease.
• If hens gain more than 0.1 pound per month after peak, reduce the energy density or limit feed intake.
• If body weight is more than 10 percent above the breed standard, implement a controlled feed restriction to prevent fatty liver.

Feed Intake Thresholds

Measure feed intake weekly. The expected intake depends on breed, age, temperature, and energy density, but a general range for commercial layers is 0.22 to 0.27 pounds per hen per day.

• If feed intake drops more than 10 percent in a week, investigate immediately. Check for disease, heat stress, water problems, or feed quality issues.
• If feed intake increases more than 10 percent without a corresponding increase in production, the diet may be too low in energy. The hens are eating more to meet their energy requirement, which increases the cost per dozen eggs.

Shell Quality Thresholds

Track the percentage of cracked eggs and eggs with poor shell quality. A rate of 2 to 3 percent cracked eggs is normal in commercial flocks. If the rate exceeds 5 percent, check the following:

• Calcium level in the diet
• Calcium particle size
• Vitamin D3 level
• Feed intake
• Water intake
• Heat stress
• Age of the flock

If shell quality declines suddenly, it may be a sign of infectious bronchitis or other disease. Call your veterinarian if the decline is rapid and accompanied by other symptoms.

Monitoring and Recordkeeping

Good feeding decisions depend on good records. You cannot know whether a diet is working if you do not track the results. This section covers the minimum records you should keep for a layer flock.

Daily Records

Keep a daily log with the following information:

• Date and age of the flock
• Number of eggs collected
• Number of cracked or broken eggs
• Number of dead or culled hens
• Feed added to the feeders (weighed or estimated)
• Water consumption (if you have a meter)
• Temperature and weather conditions
• Any unusual observations or events

This daily log is the raw data for all your feeding decisions. Take 10 minutes each day to fill it out, preferably at the same time each day.

Weekly Records

At the end of each week, calculate the following:

• Average egg production percentage (eggs per hen per day)
• Average egg weight (weigh a sample of 30 to 50 eggs)
• Average feed intake per hen per day
• Mortality rate
• Body weight of a sample of hens

Compare these numbers to the breed standard and to your own previous weeks. A gradual decline in egg production is normal after peak. A sudden drop is not.

Feed Records

Keep a record of every feed delivery, including the date, the feed type, the amount, and the batch number. This is essential for traceability if there is a feed quality problem. If you mix your own feed, keep records of the ingredient amounts and the mixing date.

Also keep a sample of each feed delivery in a sealed container labeled with the date and batch number. Store the sample in a cool, dry place for at least 3 months. If a problem arises, you can have the sample analyzed to check for nutrient levels or contaminants.

Production Curves

Plot your weekly egg production on a graph. The resulting curve should rise sharply to a peak between 25 and 35 weeks, then decline gradually. Compare your curve to the breed standard. If your peak is lower than expected, or if the decline is steeper than normal, review your feeding program and management practices.

A production curve is also useful for deciding when to transition between diets. When the curve crosses the 85 percent threshold, it is time to move from the peak diet to the post-peak diet.

Feed Conversion Ratio

The feed conversion ratio (FCR) for a layer flock is the pounds of feed consumed per dozen eggs produced. A good FCR is 3.0 to 3.5 pounds of feed per dozen eggs, depending on breed and management. Calculate the FCR monthly:

FCR = Total feed consumed (pounds) / Total dozens of eggs produced

A rising FCR means you are spending more on feed for each dozen eggs you produce. This could be due to overfeeding, declining production, or feed waste. Investigate the cause and adjust your program.

Using Records to Make Decisions

The records you keep are only useful if you act on them. Review your records weekly and ask yourself these questions:

• Is egg production on track for the breed and age?
• Is feed intake at the expected level?
• Is body weight stable or increasing appropriately?
• Is shell quality acceptable?
• Is the feed conversion ratio improving or worsening?

If the answer to any of these questions is no, identify the cause and take corrective action. The earlier you catch a problem, the easier it is to fix.

When to Call a Veterinarian or Extension Agent

Most feeding problems can be solved with adjustments to the diet or management. But some problems require professional help. Here are the situations where you should call your veterinarian or extension agent.

Sudden Drops in Feed Intake

If feed intake drops by more than 20 percent in 24 to 48 hours, do not wait to see if it recovers. This is a red flag for disease, feed contamination, or water problems. Call your veterinarian immediately. A drop in feed intake of this magnitude will cause a drop in egg production within a week, and it may take weeks to recover.

Sudden Drops in Egg Production

If egg production drops by more than 10 percent in a week, and you have ruled out feed transition issues, lighting problems, and heat stress, call your veterinarian. Diseases like infectious bronchitis, Newcastle disease, and egg drop syndrome can cause rapid production drops. The sooner you get a diagnosis, the sooner you can implement a treatment or biosecurity plan.

Poor Shell Quality That Does Not Respond to Diet Changes

If you have increased calcium, adjusted particle size, and added vitamin D3, but shell quality is still poor, there may be an underlying health issue. Infectious bronchitis is a common cause of poor shell quality, and it can affect the flock even if the hens do not show respiratory symptoms. Call your veterinarian for a flock health check.

High Mortality

If mortality exceeds 0.1 percent per week (1 hen per 1,000 per week) for more than two weeks, or if you see a sudden spike in deaths, call your veterinarian immediately. High mortality can indicate a serious disease outbreak, a toxin in the feed, or a management failure.

Suspected Feed Contamination

If you suspect that a batch of feed is contaminated with mold, mycotoxins, or an incorrect ingredient, stop feeding it immediately and contact your feed supplier and your veterinarian. Keep a sample of the feed for testing. Mycotoxin contamination can cause a range of problems, including reduced feed intake, poor production, and immunosuppression.

Regulatory or Public Health Concerns

If you see signs of avian influenza, including sudden death, respiratory distress, decreased egg production, or swelling of the head and comb, contact your state veterinarian or the USDA APHIS office immediately. Avian influenza is a reportable disease, and you are legally required to report suspected cases. Do not wait for a confirmed diagnosis to make the call.

If you sell eggs and there is a recall or a food safety concern related to your product, contact your local health department and your veterinarian for guidance.

Frequently Asked Questions

How do I know when to switch from grower feed to layer feed?

Switch from grower feed to a pre-lay diet at 16 weeks of age or when the pullets reach about 95 percent of their expected mature body weight. Move to the full layer ration when the flock reaches 5 percent egg production, which is usually around 18 to 19 weeks. Do not wait for the first egg to make the switch, because the hen needs time to build medullary bone before she starts forming shells.

Can I feed one layer ration for the entire laying cycle?

You can, but it will cost you money and may reduce the health of your flock. A single ration will be too rich in protein and energy for older hens, which increases the risk of fatty liver and wastes protein. If you cannot get a separate post-peak or late-lay feed, you can dilute the layer ration with whole oats or wheat bran after peak production, but a formulated phase feeding program is more precise and more cost-effective.

How much calcium does a laying hen need per day?

A laying hen needs about 4 to 4.5 grams of calcium per day to produce a shell and maintain her bones. A diet with 3.5 to 4 percent calcium, fed at 0.25 pounds per hen per day, provides about 4 to 4.5 grams of calcium. Older hens need more calcium because their absorption efficiency declines, so increase the calcium level to 4 to 4.5 percent after week 60.

What is the difference between a pre-lay diet and a layer diet?

A pre-lay diet contains about 16 to 17 percent protein and 2 to 2.5 percent calcium. A full layer diet contains 17 to 18 percent protein and 3.5 to 4 percent calcium. The pre-lay diet is fed for 2 to 3 weeks before the first egg to build medullary bone and prepare the digestive system for the high calcium load of the layer diet. Feeding a full layer diet too early can damage the kidneys.

My hens are laying well but shell quality is poor. What should I check?

Start by checking the calcium level in the feed and the feed intake of the flock. If the hens are eating less than expected, they may not be getting enough calcium even if the diet is adequate. Check the calcium particle size, as large particles release calcium more slowly and are more effective for overnight shell formation. Also check water intake, as dehydration reduces feed intake. If the problem persists after correcting these factors, call your veterinarian to rule out infectious bronchitis or other diseases.

How long does it take for a feed change to affect egg production?

A change in feed can affect egg production within 3 to 7 days, depending on the nutrient that is changed. Protein and amino acid changes affect production more quickly than calcium changes. If you reduce protein too much, you may see a drop in production within a week. If you change calcium, shell quality may change within a few days, but production may not be affected for a week or more. This is why gradual transitions are important.

Should I restrict feed for my laying hens?

Feed restriction is not recommended for laying hens in production. Laying hens need to eat free choice to meet their energy and nutrient requirements. Restricting feed will reduce egg production and can cause the hens to lose body weight, which delays the next egg and reduces overall production. The only time feed restriction is used is during a forced molt, and that should only be done under veterinary supervision.

Can I feed my laying hens kitchen scraps or garden waste?

You can feed small amounts of kitchen scraps as a treat, but they should not replace the layer ration. Kitchen scraps are low in calcium and protein and high in moisture, so they dilute the nutrient density of the diet. If you feed more than 5 percent of the diet as scraps, you will need to adjust the layer ration to compensate. Never feed avocado, chocolate, onions, garlic, or anything moldy, as these can be toxic or cause off-flavors in eggs.

Related Farming Guides

This section will be populated with links to related farming guides on poultry nutrition, flock management, egg production, and other relevant topics.

Related Clinical & Scientific Guides

• Poultry Farm Fencing: Materials, Design, and Predator Exclusion
• Broiler House Wind Speed and Airflow Measurement
• Broiler House Heating Systems: Types and Efficiency

References

• FAO Poultry Production: https://www.fao.org/poultry-production-products/en/
• USDA APHIS Poultry Health: https://www.aphis.usda.gov/livestock-poultry-disease/avian
• WOAH Avian Influenza: https://www.woah.org/en/disease/avian-influenza/
• FAO Animal Production and Health: https://www.fao.org/animal-production/en/
• WOAH (World Organisation for Animal Health): https://www.woah.org/en/home/

This article is educational and is not a substitute for veterinary diagnosis, treatment, public-health guidance, or regulatory reporting.