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treatment for sour crop in parrots

How To Treat Sour Crop in Parrots

Sour crop isn’t one specific condition. It’s commonly observed in hand-reared chicks due to inadequate feeding techniques, but adult parrots can develop sour crop due to bacterial and viral infections/diseases.

You can treat crop stasis by withholding food for 24-48 hours until intestinal tract motility is restored. This should be combined with fluid therapy as parrots are vulnerable to dehydration. Depending on the cause, emptying the crop, antibiotics, crop washes, and manual blockage removal may be necessary.

Sour crop affects parrots differently, but it can be fatal if left untreated. It’s can also be a sign of a more serious health condition, so get your parrot checked out by an experienced avian vet without delay.

What Is Sour Crop?

As mentioned, sour crop, or crop stasis, describes any crop infection.

It’s an unpleasant condition where the crop can’t empty properly or empties too slowly. This causes food to remain stuck in the crop, where it ferments and breaks down, resulting in an infection.

Crop infections are common in parrots as the organ is susceptible to the same things that infect the gastrointestinal tract. Bacteria usually cause crop infections, but yeast infections can also be to blame. Other causes include:

  • Burns
  • Lacerations
  • Trauma
  • Foreign objects

Sour crop is more common in hand-reared baby parrots that aren’t fed properly. If the formula’s too hot or cold, overly thick, or their incubation temperature isn’t within the right parameters, they’re at risk of developing crop problems. 

Do Parrots Have Crops?

VCA Hospitals describes the crop as a muscular pouch that appears above the top of the chest or sternum. In adult parrots, healthy crops are barely visible to the human eye.

The crop acts as a storage bag for parrots to store excess food. This benefits wild parrots that don’t know when they’re next going to find food. Parrots can’t digest this food as quickly as they find it, so the crop keeps the surplus food safe until the parrot gets hungry within 24 hours after ingesting it.

This removes the risk of starvation. Adult parrots also produce crop milk from the crop, which is a secretion of the cells that line it. They use this milk to feed their newly-hatched chicks.

sour crop symptoms in parrots

How to Tell if a Parrot’s Crop Is Full

In young parrots, the crop is visible. So, you can see if it’s full by looking at it. You can check the crop’s fullness in older parrots by gently feeling it with your thumb and index finger.

A full, healthy crop feels soft and mushy, a bit like a balloon filled with water. When the crop’s impacted or infected, it’ll feel hard and swollen. The crop won’t empty overnight, remaining firm in the morning when it should be empty.

How Long Does It Take for a Crop to Empty?

Once food enters the crop, it empties between 8-12 hours. However, it can sometimes take up to 24 hours for all the food to be completely gone.

If the crop does not empty by the time the parrot wakes up, it likely has sour crop.

What Causes Sour Crop in Parrots?

There are various causes of sour crop, including problems with the digestive tract, toxicities, and metabolic diseases. The most likely causes of crop issues are:

Yeast Infection

When food stays in the crop for too long, the acidity changes and throws the digestive system off balance, disrupting the natural balance of bacteria.

In particular, candida, which is a fungal species, overpopulates and proliferates into large white plaques, impairing the crop’s ability to function properly. When the infection becomes severe, candida grows into the esophagus and mouth, causing visibly white patches.

As a result of too much Candida within the body, the crop slows down altogether, and leftover food ferments inside it. This creates a foul smell, giving the condition its name, “sour crop.”

Bacterial Infection

Harmful bacteria come from other parrots, dirty food and water bowls, or foods that have been left in the cage for too long, especially fruits and vegetables that spoil quickly.

Sometimes, bacteria found in the intestinal tract overpopulate and weaken the immune system. It’s an even more significant problem if the parrot’s stressed, as the bird’s body is more susceptible to health conditions.

Also, the inappropriate use of antibiotics can lead to bacterial overgrowth.


Roundworms and tapeworms are a problem. Similarly, trichomonas, which are protozoan parasites, are responsible for sour crop in smaller birds, such as budgerigars and cockatiels.

As described by Science Direct, the parasites colonize the crop, preventing it from functioning and impairing its ability to empty itself of food.


A foreign body inside the tract can impact the crop, preventing it from working correctly.

In severe cases, the impact affects the proventriculus (glandular stomach). This is where the food gets softened and broken down by gastric acid. Common obstructions include:

  • A piece of food that’s too large, such as celery
  • String, rubber, or plastic toys
  • Bark
  • Wood shavings
  • Grit

To prevent crop impaction in parrots, cut all food into bitesize pieces and throw toys away once they’re broken.

Improper Hand-Feeding

Insufficient weaning hand-feeding methods are likely to cause sour crop in newborn parrots.

If the formula’s too hot, cold, or thick, it’ll affect the crop’s ability to empty itself, causing the food to ferment. This leads to secondary bacterial and yeast infections.

Insufficient fluids are another cause. That’s because the parrot becomes dehydrated, and fluid gets pulled from the intestinal tract, causing an obstruction due to the thickened, dry food.

Improper Environmental Temperature

Incorrect incubation temperatures can cause newborn chicks to develop crop stasis.

If the temperature’s too warm or cold, a parrot’s at risk of dehydrating or overheating. If the chick’s feeling cold, it’ll use all its body heat to keep warm, leaving no energy for digesting food.

As described by MSD Vet Manual, the recommended temperature for newborn parrots is between 92-94°F. Owners mustn’t allow this to drop as chicks can’t regulate their own body temperature.

Viral Diseases

Several viral diseases cause crop stasis, including:

  • Proventricular dilation disease
  • Polyomavirus
  • Herpes virus

While all symptoms vary based on the virus, they all cause the movement of food to slow down. Each virus does this differently, but the outcome is the same.


Heavy metal toxicity from the consumption of lead or zinc is common in parrots and affects the gastrointestinal tract.

This is commonly caused by powder-coated cages and zinc-based water and food bowls. Worryingly, some parrots go on to develop crop stasis and neurological symptoms, leading to permanent damage.


Goiter most commonly occurs in budgies with iodine deficiencies or parrots on an all-seed diet.

It causes the thyroid glands (located on either side of the crop) to enlarge, blocking the crop’s outflow and causing the trapped food to ferment.

Metabolic Diseases

Metabolic diseases prevent the proper function of the crop and disrupt the digestive and intestinal tract.

These diseases include:

  • Liver disease
  • Diabetes mellitus
  • Renal disease

In these cases, sour crop is a symptom of these diseases.

Signs of Sour Crop in Parrots

While there are several causes of sour crop, it’s relatively easy for owners to diagnose. That’s because the symptoms manifest shortly after the condition develops. The most common symptoms include:

Hard Crop

As mentioned, a healthy, full crop feels soft and mushy, like a water-filled balloon.

However, once it’s impacted, it’ll become hard and noticeably swollen. This is known as crop overdistention. The crop should empty itself by the morning. If it hasn’t, crop infection is the likely explanation.

By gently pressing on the crop, you may hear gurgling sounds from the gases being produced. Be careful not to press too hard on the crop as it’s likely to feel sensitive and sore.

Foul Odor

Crop stasis is known as “sour crop” because infected crops emit a foul odor caused by a combination of bacteria, yeast, and fermenting food. As the food rots, it releases various gasses that exit the body through the mouth.

Owners recognize the smell as sour crop almost instantly as unpleasant-smelling breath is most commonly the result of a crop infection disrupting the body’s delicate balance of bacteria.

Regurgitation and Vomiting

Regurgitation is normal and allows parrots to clear their crop at least once a day – more often in the morning than at any other time. But frequent or chronic regurgitation is a sign that something’s wrong.

Your parrot might regurgitate clear liquid or fully undigested food. It depends on how serious the sour crop is. Your parrot will also vomit if it has crop stasis. This is less frequent but signifies that the infection is serious.

When vomiting, parrots will:

  • Appear visibly stressed
  • Uncontrollably expel the contents of their stomach
  • Produce partially or mostly digested food

At this point, your parrot will need veterinary care.

Undigested Food in Droppings

Undigested food in your parrot’s droppings indicates that its digestive tract isn’t working properly.

It’s usually the sign of infection, which links directly to sour crop. As well as undigested food, parrots with crop stasis develop diarrhea and foul-smelling stools. The amount of droppings sometimes decreases.

You should monitor your parrot’s poop for any changes. Any alterations to your parrot’s feces or toilet habits could be a cause for concern, particularly if you notice any other worrying symptoms of sour crop alongside them.

Decreased Appetite

Because your parrot’s crop is full, your parrot won’t want to eat anything else until the food that’s stuck gets removed.

In severe cases of crop stasis, where burns or lacerations are the cause, it’s likely too painful for your parrot to eat at all. As a result, the parrot will fail to gain weight or lose weight. In newborn chicks, this can be fatal.

Long periods of appetite loss are abnormal and should be investigated to rule out sour crop.


Parrots with sour crop become dehydrated, and their skin color changes from a healthy pink to a much brighter red, depending on how severe the condition is. The skin will also lose its elasticity. 


According to Avian Medicine, parrots with sour crop quickly become listless as the disease progresses.

That’s because parrots with the condition have no energy due to the lack of food. Similarly, the body has to draw on its energy reserves to function properly.

Lack of Feeding Response

The feeding response in parrots with sour crop varies from normal to absent. This is more common in newborn chicks. While feeding them their formula, you may notice that they refuse to eat it.

This is a serious problem because fragile chicks become weak quickly.

How Is Sour Crop Diagnosed?

In many cases, it’s easy to tell that your parrot has sour crop from the crop’s fullness and foul smell alone. That’s because the odor is one of the most noticeable signs.

Also known as a crop lavage or crop infusion, a crop wash is one of the most effective ways to diagnose sour crop. Only vets or experienced owners with a history of caring for parrots should attempt crop lavage.

During the procedure, the vet will place a small amount of water into the crop through a feeding tube. Some of the fluid is removed and tested for organisms.

A direct microscopic examination is sometimes enough to diagnose sour crop, but if it’s not, the vet will swab the crop, take an x-ray, or perform a biopsy. They may also take a blood profile.

Other testing methods include:

  • Physical examination
  • Sampling of the parrot’s feces to test for infection and inflammation
  • Serum biochemistry panel
  • Barium contrast study to detect the slowing of intestinal motility, foreign objects, and tumors
  • Infectious disease testing
  • Endoscopy

Treatment for Sour Crop in Parrots

There are various treatments available for crop stasis in parrots. They vary depending on the cause and severity of your bird’s sour crop and include:

Withhold Food

Stop feeding your parrot until you resolve the problem.

Adding more food to a crop that can’t empty itself will only make things worse. Your parrot also won’t benefit from the nutritional content because the body can’t use it. Your parrot can survive for 1-4 days without food.

Once your parrot’s intestinal tract motility returns, feed it easy-to-digest foods.

Fluid Therapy

Parrots with crop stasis are often dehydrated. To provide them with fluids, vets will use:

  • Intravenous catheter
  • Interosseous catheter (into the bone marrow)
  • Subcutaneously (under the skin)

Which one is used depends on the severity of your parrot’s dehydration.

Manual Emptying

You can manually empty the crop to remove fermenting food.

To do so, hold the parrot with its head facing down and get as close to the bottom of the crop as possible. Gently massage it, being careful not to push it up, as the parrot may aspirate the food into its trachea.

Use a cotton pad or Q-tip to wipe away any formula or liquid that exits the mouth.

Crop Wash

In severe cases of sour crop, a crop wash is the only way to remove fermenting food.

A vet will place a catheter into the mouth and vacuum the contents out using a syringe. After removing the contents, the vet will rinse the crop using warm water, Pedialyte, or Lactated Ringer’s solution.


When bacteria cause sour crop, your vet will administer a course of antibiotics to treat the infection.

If the crop has some motility, they will provide oral antibiotics. But if the crop has stopped working altogether, your vet will inject them into your parrot’s system.

Nystatin is most commonly used for yeast infections. It’s not an antibiotic but an antifungal medicine that clears up yeast overgrowth.

Apple Cider Vinegar

Apple cider vinegar can also clear up yeast infections, as it has antibacterial and antioxidant properties.

It encourages the digestive system’s acidity, promoting the growth of healthy bacteria. Therefore, add diluted apple cider vinegar to your parrot’s water or food to ease its sour crop symptoms.

Remove the Foreign Body

If a foreign body causes the parrot’s sour crop, surgery will be required to remove it, especially if the foreign body is an inedible object, such as plastic or string. This will need to be carried out quickly to prevent death.

However, if the blockage is caused by digestible food, you could try massaging the crop using the techniques we’ve discussed to remove it naturally. This procedure stimulates the crop and encourages it to empty itself.

best source of protein for parrots

How Long Does It Take Sour Crop Treatment to Work?

If you’re treating your parrot with a water-only diet, the main symptoms of sour crop should disappear within 48 hours. Sometimes parrots feel better in as little as 24 hours, but this depends on the severity.

You may discover that your parrot has frequent bouts of sour crop during its recovery. While this isn’t uncommon, it could indicate a health condition, such as a virus, causing the problem.

How To Prevent Sour Crop?

While sour crop is a common condition, there are specific steps that you can take to reduce to likelihood of it occurring in the first place. The best preventative measures include:

  • Cut up food into small, bite-sized pieces
  • Remove food after 2-4 hours to prevent it from germinating or going moldy
  • Change the drinking water often
  • Remove all broken toys and games to prevent obstructions
  • Avoid zinc parrot cages and accessories and choose stainless steel
  • Always keep newborn chicks at the right temperature
  • Never feed formula that’s too hot or thick
  • Add probiotics to your parrot’s diet

These steps will help keep your parrot’s digestive system and intestinal tract healthy.

Is Sour Crop Fatal?

If you identify your parrot’s sour crop early enough, the condition is rarely fatal with proper treatment.

However, if it goes undetected, it can kill your parrot. Similarly, the mortality rate of sour crop depends on the cause. A tumor, obstruction, or metabolic disease is more serious and can’t always be cured.

Bacterial and yeast infections, while potentially serious, are easier to clear up after a course of antibiotics.

Monitor your parrot every morning to check that the crop has emptied properly. Similarly, if you notice any symptoms that give you cause for concern, take your parrot to a vet for checks.