The crop is the gateway to a chicken’s stomach. Ensuring that the crop is functioning properly is essential for keeping your flock healthy and productive! There are two common ailments that affect the crop: sour crop and impacted crop. Learning to tell the difference between sour crop vs impacted crop in chickens will be key to properly diagnosing a crop issue in your homestead flock. Sour crop can lead to malnutrition and a decline in health. Impacted crop can be fatal. You should be aware of how to diagnose a crop problem, what causes crop problems, and how you can prevent them, so let’s dive in!

a Bielefelder hen

This post may contain affiliate links. See our Disclosure for more information.

What is the crop?

The crop is a sac-shaped organ muscle attached to a chicken’s esophagus. It is located just below the neck above the breast. The crop functions as a food storage location. When a chicken consumes food, it travels down the esophagus and into the crop. The crop has a slightly acidic pH level and is home to a host of beneficial bacteria and enzymes. The bacteria and enzymes begin the process of breaking down the food prior to digestion.

The food can then be slowly released from the crop to be fully digested by the chicken’s gizzard, stomach, and intestines. Crop problems occur when the crop is inhibited from properly releasing food for continued digestion.

On a chicken, you can often see when the crop is full because it will look like your hen swallowed a baseball! Her crop will be round and distended above her breast. A full crop is not necessarily reason to panic. Throughout a day of foraging or free-ranging, a chicken will store the food it consumes in its crop. Then at night, the food will be released from the crop for further digestion.

homesteader me
a Buff Orpington hen

How to Diagnose Crop Problems

If you suspect your chicken has a crop problem, you should perform a crop-fullness test. You can perform this test on your whole flock, or you can quarantine an individual hen that you suspect may have a crop problem.

To diagnose a crop problem, you will want to remove the food and water sources in the evening after your flock has roosted. Over the course of the night a chicken’s crop should properly empty and any stored food will be digested.

In the morning, check on the crop of the chicken who you suspected had a crop issue. Notice how the crop looks and feels:

  • empty crop- will be hard to distinguish and will feel small, flat, and hard
  • full crop– will look extended and feel round and full

If the crop is still full in the morning, then you will know that your hen has a crop problem. From here, you need to diagnose whether it is a case of sour crop or impacted crop.

Keep in mind that crop issues are typically individual ailments, and only one bird may be affected. However, if a common crop problem trigger is consumed by the whole flock, more than one member of the flock may be affected.

an olive egger hen

What is Sour Crop?

Let’s start by looking at sour crop. Sour crop is a fungal infection of the crop. It is caused when the pH levels of the crop change, allowing bad bacteria and fungus, specifically Candida albicans, to proliferate. The bad bacteria and fungus then inhibit the crop’s contents from continuing on to further digestion. When food remains in the crop for an extended period of time, it will trigger fermentation of the crop’s contents.

The normal pH levels of a healthy crop are slightly acidic at a pH level around 5.5. A slightly acidic environment is optimal for beneficial bacteria to thrive and break down the food contents. Whenever something causes the crop to not release food properly, it can cause a pH level change in the crop. When the pH levels change, it can kill off the good bacteria and allow bad bacteria and fungus to proliferate.

One such fungus that causes sour crop is Candida albicans. Candida albicans is a fungus that appears as white patches of plaque in a chicken’s crop and can even develop in the mouth and throat. The white plaque, or fungus, inhibits food from being released from the crop. It also causes the crop walls to thicken, decreasing the overall size of the crop.

When the food isn’t released from the crop, it starts to ferment. The fermentation process is what gives sour crop its name and provides the accompanying ‘sour’ smelling breath.

Sour crop can be triggered by impacted crop, since an impaction would prevent food from being released from the crop and could lead to a pH change.

Symptoms of Sour Crop

  • Crop- will feel full and squishy even after a night of food and water withdrawal
  • Lethargy
  • ‘Sour’ smelling breath
  • Gurgling noises from the crop (from the fermentation process)
  • Lack of appetite and water consumption
  • Weight loss
  • Diarrhea
  • Drop in laying
natural poultry first aid kit supplies checklist free printable
backyard chickens eating out of a hanging feeder

What is Impacted Crop?

Now that you know what sour crop is, let’s discuss impacted crop. Impacted crop is another problem that affects a chicken’s crop. Impacted crop occurs when food becomes compacted in the crop and cannot be released on to the gizzard for further digestion. The compacted food in the crop creates a blockage which prevents normal functioning of the crop.

Because impacted crop creates a blockage in the crop, it can easily lead to sour crop if the contents cause an upset in pH levels and start to ferment. However, often times the food contents are so impacted that they do not break down enough to start fermenting.

Impacted crop is a potentially fatal condition. It prevents food from continuing on through the digestion process, which leads to nutrition deficiency and emancipation. A chicken cannot get the nutrition from its food if the food never gets released from the crop. The impaction can also become so large that the crop may start to press against the windpipe, leading to suffocation.

While both sour crop and impacted crop affect the crop, they are two different conditions that must be treated differently. Here’s a brief recap comparing the two ailments:

  • Sour Crop- a pH change occurs in the crop which allows bad fungus to grow and causes fermentation of the crop’s contents
  • Impacted Crop- the crop’s contents get impacted, causing a blockage in the crop which prevents food from being released from the crop

Symptoms of Impacted Crop

Impacted crop can sometimes be hard to diagnose since the symptoms are often subtle until the condition becomes serious.

  • Crop- will feel large, full, and hard even after a night of food and water withdrawal
  • Lethargic
  • Emancipation and weight loss
  • Lack of droppings
  • Stopped laying
  • Weakness
  • Difficulty breathing (if the impaction starts to press against the windpipe)
a flock of chickens eating fermented feed out of a bowl

Causes of Crop Problems

Sour crop is a condition caused when the crop does not empty properly. Impacted crop is a condition that occurs when the crop’s contents become impacted, causing a blockage which inhibits the crop from emptying properly. While both of these crop problems can have similar causes, both sour crop and impacted crop do have specific triggers.

Sour Crop Triggers:

Long Grass- Long grasses can prevent the crop from properly emptying. Not only can the grasses get impacted, leading to impacted crop, but they can also cause a change in the pH levels of the crop if they stay in the crop too long.

Coop Litter– Certain coop litters, like straw and wood shavings, are tough and fibrous. Tough and fibrous foods have a harder time being broken down in the crop. When the foods remain in the crop for an extended period of time they may start to ferment, leading to sour crop.

Worms– Worms, particularly capillary worms, will inhibit proper crop function and can cause malnutrition. They will prevent the crop from emptying properly and can alter the pH levels of the crop.

Non-Natural Antibiotics– Synthetic antibiotics alter the pH levels in the crop, making the crop a more suitable place for bad bacteria to thrive. The synthetic antibiotics can also kill off both good and bad bacteria, making way for bad fungus to develop in the crop.

Foreign Objects– Foreign objects (basically anything that is non-edible) will affect how the crop functions. Objects such as string and twine can inhibit the crop from properly releasing food, which then allows the food to ferment. Sharp or hard objects can damage the crop or cause a blockage.

Moldy Feed & Treats– Since mold is a fungus, it can encourage the growth of more fungus once it enters the crop. It will also alter the pH levels in the crop, leading to an increased chance of sour crop if the pH levels are not restored quickly.

Impacted Crop Triggers:

Long & Fibrous Grass– Long, fibrous grass and foods have a tendency to ball up and create a blockage in the crop. Since these foods cannot be broken down as easily, they remain in the crop for longer. If they build-up in the crop, they can become compacted and lead to impaction.

Coop Litter Consumption– Since coop litter is often tough and fibrous, those materials can easily cause an impaction in the crop. Litter such as sand can also lead to impaction if it is consumed in large quantities.

Foreign Objects– Foreign objects that can’t be digested can cause a blockage. The objects may also combine or entangle with other foods in the crop, causing an impaction.

Gorging on Feed– Consuming too much feed all at once can lead to an impaction. The sudden influx of food in the crop can affect how well it functions. Impaction is also more likely to occur if a chicken does not drink enough water to help keep the food soft and digestible.

two fresh eggs in a jar of chicken feed grains

How to Prevent Crop Problems

Provide Free-Choice Access to Grit-

Chickens will naturally be inclined to consume small particles of dirt and rocks, which help break down the food in both the crop and the gizzard. Chickens who are pasture-raised, free-range, or whose coop or enclosure litter is sand usually don’t need supplemental grit.

However, if your flock doesn’t have access to some sort of coarse dirt, then you will want to provide them with a dispenser of layer grit separate from their feed to eat free-choice.

Prevent Over Consumption of Tough & Long Grasses-

Don’t feed your flock handfuls of long, tough grass and also limit foraging time in areas that have tough, fibrous grasses. If you use straw in the coop or enclosure, make sure you buy quality straw that is long shafted and contains some leftover grain heads. The leftover grain heads will give your chickens something to forage for in the straw instead of eating the straw.

Pine boughs can be used during the winter as a boredom buster, however, use them in moderation and monitor your flock for the first couple of times you provide pine boughs. Chickens only like the long-needled species of pine (like white pine), so be cautious and watch to see that the chickens don’t over consume the long pine needles.

Prevent Feed Gorging-

Always make sure your flock has free-choice access to a high-quality feed all day long. Chickens instinctually will forage for food throughout the day, so the free-choice feeding method is natural for chickens.

Ensure that your flock also has access to plenty of clean drinking water all day too! Water will help keep the crop contents soft and digestible.

Avoid Foreign Objects-

Don’t leave small, shiny objects near or around the coop. Avoid using string for making treat garlands or other interactive toys since string breaks easily and can accidentally be consumed. In general, keep your flock from eating any un-edible objects!

Prevent Litter Consumption-

Chickens are not naturally inclined to consume the coop litter unless they are really hungry! Sometimes boredom can lead to litter eating, so make sure your chickens stay stimulated with constructive activities. Foraging and boredom busters can help prevent boredom eating.

Chickens may also accidentally consume litter if it gets tossed into their feeder, flung into their water source, or sticks to any treats they are given. Using hanging systems for the feeder and water can help keep the food and water source clean. Providing treats in designated treat bowls or treat dispensers can help prevent litter from sticking to the treats.

Prevent Worms-

Proper flock management and coop cleaning can help keep worms to a minimum. Free-range flocks will naturally encounter sources of worms. However, they can also build up a natural immunity to the worms as long as the worm source is kept in check.

Keeping the chicken coop and coop enclosure clean and dry can prevent worm hosts from bringing the parasites to your flock. Give your flock natural worm preventatives on a regular basis to help them fight any small parasite loads they might be dealing with.

Use Natural Probiotics-

Natural probiotics promote the proliferation of good bacteria in the crop. By giving your flock natural probiotics, you are encouraging the growth of good bacteria in the crop. The good bacteria will competitively exclude any bad bacteria or fungus from growing.

You can give your flock a natural probiotic supplement as frequently as once a week. Alternatively, make your flock some fermented feed once a week. Fermented feed naturally contains probiotics and will provide a host of other benefits for both you and your flock!

the trading post
a circle of farm fresh eggs ranging in color from cream to light brown

Managing your flock well and feeding them a wholesome, homestead diet should help prevent any crop issues from ‘cropping’ up in your homestead flock! Sorry, I couldn’t resist! Ensuring the crop is functioning properly, and releasing food for further digestion, is important so that your chickens can get the nutrition they need from their feed. Being fully educated about sour crop and impacted crop, including how to tell the two apart, is one more tool in the first-aid box that will help you keep your flock healthy!

  • Impacted Crop– caused by an impaction of crop contents, crop will feel full and hard, can be fatal
  • Sour Crop- caused by a pH change and fermentation of crop contents, crop will feel full and squishy, often accompanied by sour smelling breath

Make sure you don’t miss any of other tips for raising a healthy homestead flock, join our modern pioneer newsletter community! Feel free to reach out with questions at any time too!

by Alexa

Sour Crop vs Impacted Crop in Chickens- learning to tell the difference between sour crop and impacted crop will help you diagnose any crop problems in your flock! You will also learn what causes crop problems and how to prevent them! | The Pioneer Chicks | Raising Chickens Like a Pioneer | raising chickens | chicken health | raising chicken naturally | #chickens #homesteading #health
Sour Crop vs Impacted Crop in Chickens- learning to tell the difference between sour crop and impacted crop will help you diagnose any crop problems in your flock! You will also learn what causes crop problems and how to prevent them! | The Pioneer Chicks | raising chickens | chicken health | raising chicken naturally | #chickens #homesteading #health
Sour Crop vs Impacted Crop in Chickens- learning to tell the difference between sour crop and impacted crop will help you diagnose any crop problems in your flock! You will also learn what causes crop problems and how to prevent them! | The Pioneer Chicks | raising chickens | chicken health | raising chicken naturally | #chickens #homesteading #health