how does a parrot's digestive system work?

How Does A Parrot’s Digestive System Work?

Parrots have a unique digestive tract. Parrots don’t chew their food like mammals because they don’t have any teeth, so they rely on their digestive systems to stay healthy. All organs within the tract are small, compact, and light to help parrots remain in the air for as long as possible, even when they’re digesting food.

Parrots’ digestive systems are adapted to pulverize food so that it can move through the gut. The crop is a muscular pouch that enables parrots to store a larger amount of food than they can consume. Digestive problems include parasites, avian gastric yeast, thrush, Pacheco’s disease, and proventricular dilatation disease. 

Parrots are at risk of starving if they don’t get enough food, so their digestive systems are designed to work quickly. To enable this, parrots need a well-balanced, healthy diet featuring foods that are easy to digest.

How Do Parrots Digest Food?

Parrots have an efficient way of digesting their food. Digestion involves several organs, all of which are an essential part of the process. Because parrots eat a range of foods that are hard to digest, like seeds and pellets, the digestive process is well adapted to cope with these foods in the body.

The digestive system is also adapted to get the most from the food a parrot finds in the shortest amount of time. This is key to its survival from starvation and predators who know to attack when a parrot is preoccupied with eating. The parrots’ digestive system process and the organs that are involved are as follows:

Mouth and Tongue

Once a parrot has torn or scooped the food into the mouth, the tongue pushes it into the digestive tract. The tongue is also sometimes used to hold wriggling worms, grubs, and other insects in place.

As mentioned, parrots don’t chew their food like mammals because they have no teeth. This is why parrots drop food down their throat instead, hence why parrots are messy eaters. Teeth would prevent parrots from being aerodynamic during flight, so they have beaks instead.

Another vital part of the digestive tract is the pharynx, which is the part between the mouth and esophagus that enables parrots to swallow food.

Esophagus

The esophagus is what food moves down to get to the parrot’s stomach. The esophagus can expand and sits on the right side of the neck in birds. It’s large in diameter, allowing parrots to swallow larger meals. Swallowing is also aided by the extension of the parrot’s neck.

Crop

The crop is a type of storage bag. It’s a muscular pouch found in the parrot’s neck above the top of the chest or sternum. The crop isn’t always visible to the human eye.

Parrots, particularly those in the wild, fill themselves up as much as possible when they find food. This is mainly because they won’t know when their next meal will come.

Food can’t be digested as quickly as it’s consumed, so the crop allows parrots to store surplus food. Parrots can digest this food at a later date when it’s rested and able to avoid predators.

parrot digestive problems

Proventriculus

Once the food moves on from the crop, it enters the proventriculus, which is sometimes known as the glandular stomach.

Parrots have a two-chambered stomach, and the proventriculus is the first of them. It’s a rod-shaped organ located between the esophagus and gizzard.

Here the food is softened and broken down by gastric acid, mucus, and various digestive juices produced in the organ.

Gizzard

The gizzard is the second chamber of the stomach and is located towards the hind part of the parrot.

It consists of tough muscles and a thick wall that grind food into smaller pieces. Parrots commonly swallow sand, small pebbles, and grit while eating, which the gizzard uses to pulverize the food.

Sometimes, tough pieces of food move between the proventriculus and gizzard to break it down more efficiently. The gizzard is commonly compared to the teeth of other animals, as it does a similar job, albeit further in the body.

Small Intestine

Once the food is broken down, it moves into the parrot’s small intestine. At this point, the liver and pancreas absorb the essential nutrients that the parrot needs. The waste products are passed through to the next stages of the digestive system. The small intestine is divided into three parts:

Duodenum

The duodenum is the first part of the small intestine, located between the stomach and jejunum. It’s responsible for breaking down partially digested food using enzymes and begins the process of absorbing nutrients.

It also produces hormones and receives secretions from the liver and pancreas. These fluids neutralize the acidity of chyme traveling from the stomach to prevent digestive problems and damage the gut lining.

Jejunum

The jejunum is the middle part of the small intestine and is nestled between the duodenum and the ileum, making up two-fifths of the small intestine.

With the assistance of pancreatic enzymes and bile produced in the liver, the stomach contents move down through the duodenum and enter the jejunum. Its primary function is to absorb essential nutrients, which then enter the bloodstream to be distributed to the body’s organs.

Ileum

The ileum is the final section of the small intestines and weighs around 20% to 50% less than the jejunum, enabling a parrot to stay in the air while flying. It makes up about 60% of the entire small intestine length.

Some absorption of fat, protein, and starch occurs in the ileum, but it’s mainly a water and mineral absorption site. It also absorbs vitamin B12, which is essential for a parrot’s health.

Large Intestine

Leftover material travels through the large intestine. The primary purpose of it is to reabsorb water.

In parrots, the large intestine’s role during the digestive process is mostly redundant compared to a mammal’s large intestine and plays little part. It’s also much shorter in birds.

Rectum

The rectum is a short tube that connects the intestines to the cloaca, also known as the colon. It’s at the end of the intestine and has no other function other than to allow undigested food to pass through into the cloaca.

Cloaca

The cloaca acts as a storage facility for feces and urine. Waste accumulates here before being released from the body. When the parrot is ready to release its urine or feces, the waste is expelled through a sphincter at the base of the cloaca.

Common Parrot Digestive Problems

Parrots can have a range of digestive disorders. Most are easily treatable, but owners must keep an eye on their parrots for any changes to their feces or weight, as these are common indicators that a parrot isn’t digesting food properly.  The most common parrot digestive problems include:

Avian Gastric Yeast

As described by the MSD Veterinary Manual, avian gastric yeast colonizes the digestive tract of birds. Parrots with a weakened immune system are most commonly affected, as are lovebirds, budgerigars, parrotlets, and cockatiels. Symptoms of avian gastric yeast include:

A vet will examine the parrot’s droppings under a microscope. If organisms are present, they will recommend a course of treatment to reduce them and improve the parrot’s health.

The rate of death in affected parrots varies from 10% to 80%. Stronger strains of yeast are more likely to be fatal. If a parrot recovers, relapses are likely, so close monitoring is required for the rest of the parrot’s life.

Parrots can also shed the organisms in the droppings. Therefore, the parrot’s droppings must be cleaned from the cage to prevent the infection from getting back into the body.

Unfortunately, the infection can be transmitted between parrots. If you own more than one, you must be careful not to spread the infection. Quarantining the affected parrot is essential to stop the spread.

Candidiasis (Thrush)

Thrush is a common environmental fungus that’s caused by the Candida albicans yeast. It’s usually found in small numbers in a parrot’s digestive tract. Symptoms include:

Thrush is more common in young, unweaned parrots that are on antibiotics. This is because they have undeveloped immune systems that are more susceptible to illness.

Similarly, adult parrots with malnutrition or on antibiotics for other diseases are prone to developing thrush. Thrush can be spread from adult parrots to younger parrots or through a contaminated environment. Candidiasis usually affects a parrot’s:

  • Crop
  • Stomach
  • Intestines
  • Skin
  • Respiratory tract
  • Central nervous system

Treatment for candidiasis includes antibiotics. However, antibiotics can kill off good bacteria in the parrot’s gut, disturbing the digestive tract’s function.

The severity of thrush depends on the immune system’s condition, regardless of the affected parrot’s age. A vet will recommend a reduced feeding program to help the parrot empty its crop properly. Medications may clear the infection. To prevent candida from forming in your parrot’s environment:

  • Regularly disinfect the cage, nest box, and feeding utensils
  • Provide clean food and water
  • Keep affected parrots away from other birds

Proventricular Dilatation Disease (PDD)

Also known as macaw wasting disease, proventricular dilatation disease is an illness that affects the digestive tract’s nerves. It stretches the stomach and prevents the normal function of the muscles required for digestion. The damaged nervous system stops nutrients from being absorbed or digested.

Proventricular dilatation disease is caused by an avian bornavirus that occurs after exposure to the feces of infected birds. It can also be spread when affected parrots share a cage or housing. Signs of PDD include:

  • An initial increase in appetite
  • Chronic weight loss
  • Undigested food in the feces
  • Smelly stools
  • Regurgitation
  • Convulsions
  • Head tremors
  • Weakness
  • Incoordination
  • Blindness
  • Difficulty perching
  • Leg paralysis

Outbreaks of proventricular dilatation disease are uncommon, but they can be fatal. It’s incurable, but it can be managed with palliative care. The only way to prevent transmission of the disease is to isolate the stricken parrot.

Its cage needs to be disinfected to remove traces of the infection. Ventilation can also reduce transmission rates. The infection doesn’t survive for long, so good hygiene will stop the spread of the disease.

To treat the parrot, easily digestible foods need to be provided. The use of anti-inflammatory medication is sometimes required, too.

Pacheco’s Disease

The psittacine herpes virus causes Pacheco’s disease. It leads to a viral inflammation of the liver and commonly affects Amazon parrots, conures, hawk-headed parrots, and macaws. Symptoms include:

  • Lethargy
  • Diarrhea
  • Ruffled feathers
  • Sinusitis
  • Anorexia
  • Conjunctivitis
  • Neck, wings, and leg tremors
  • Discolored urine and feces

The disease is highly contagious and transmitted through contaminated feces and nasal discharge. It can also spread through direct contact with sick birds and contaminated food and water.

Pacheco’s disease sometimes appears as pink, cauliflower-lie growths called papillomas. Papillomas grow in the mouth and digestive tracts, causing wheezing open-mouthed breathing, and difficulty swallowing. 

Papillomas that grow in the digestive tract can also cause vomiting and a loss of appetite. They sometimes also protrude from a parrot’s vent and can be seen when the parrot strains while defecating.

Surgical removal of papilloma is likely needed. However, growths may recur, so palliative treatment is usually the only realistic course of action. Pacheco’s disease kills quickly, so vaccinate your parrot to protect against the disease to reduce the chances of it occurring.

Gastrointestinal Parasites

Intestinal parasites are common in parrots. Various parasites affect parrots, including:

Giardiasis

Giardiasis occurs when microscopic single-celled parasites called protozoa get into the intestines. It’s most common in cockatiels but affects most parrot species. Adult parrots are often carriers. Transmission of the disease occurs when other birds eat infective cysts. Giardiasis causes:

  • Diarrhea
  • Malnutrition
  • Inability to absorb nutrients
  • Itching, which causes the parrot to pull or dig at its feathers
  • Abnormally large droppings
  • Thinness
  • Poor feathering
  • Excessive crying

Oral medications are often used to treat giardiasis.

how parrots feed and digest food

Trichomoniasis

Trichomoniasis is also known as frounce or canker. It’s a protozoan infection that causes whiteish-yellow lesions on the mouth and throat lining, crop, and esophagus.

While the lesions aren’t always visible, infected parrots display signs of increased salivation and regurgitation. It’s transmitted through direct contact or by contaminated food and water. Treatment involves oral medications administered by a vet.

Roundworms

There are many different types of roundworm, all of which reside in a parrot’s digestive tract. Roundworm is transmitted when a parrot eats roundworm eggs. Affected parrots show signs of weakness and emaciation. Roundworm can even lead to death if roundworm blocks the intestines.

Vets will examine a parrot’s feces for parasitic eggs. Oral medications can kill worms. If the roundworms coil into a bunch and obstruct the intestines, surgery might be needed to remove them.

Tapeworms

Tapeworms are one of the more uncommon parasites, especially in captive parrots. However, they’re often found in cockatoos and African grey parrots.

Parrots become infected by eating food contaminated with tapeworm eggs. Once they reach the bowels, the tapeworms grow a ribbon-like body containing several packets of eggs that fall off while in the digestive tract.

The eggs exit the body through the parrot’s droppings, and insects then consume the eggs. In turn, the insects are eaten by parrots, continuing the cycle. Symptoms of tapeworms include:

  • Weight loss
  • Quietness
  • Loose droppings
  • Nutritional deficiencies
  • Change in appearance
  • Loss of appetite

A vet will need to recommend the appropriate treatment. Administering this treatment to your parrot and cleaning the area where it most likely came into contact with the parrot should clear the symptoms.

Why Is My Parrot Regurgitating?

Regurgitation is sometimes a sign that there’s something wrong with your parrot’s digestive tract. However, regurgitation is also normal.

When a parrot does so, it’s more like a spitting action than a vomiting motion. The parrot will shake its head from side to side before expelling undigested or partially digested food. These are some common reasons for regurgitation:

Behavioral Traits

In many cases, regurgitation is a normal behavioral trait that some parrots exhibit. Parrots only do this around humans they’re comfortable around and bonded with. Thankfully, behavioral regurgitation isn’t a sign of a medical condition. However, it can be unpleasant to witness.

It usually happens when parrots respond to stimulation. This could be during a fun game, which causes the bird to become over-excited. Parrots may also regurgitate after being petted in their favorite spot.

In the wild, parrots regurgitate food for birds they’re mated with and their young. Therefore, if a parrot does it to you, they see you as someone they love.

Health Issues

As mentioned, a range of health issues can cause regurgitation. Similarly, if it’s a regular occurrence, your parrot could have a blockage. This will be fatal if left untreated.

Young parrots are sensitive to the temperature and consistency of food. Switching food too quickly can be problematic and causes some parrots to reject it altogether. They will regurgitate to get the food out of their system before it goes through the digestive process.

How To Help A Parrot’s Digestion

The primary purpose of a parrot’s digestive tract is to absorb as many nutrients as possible from the consumed food. Parrots need their digestive tracts to operate smoothly. If the digestive process encounters problems, the parrot is at risk of becoming malnourished. To help a parrot’s digestive tract work efficiently, do the following:

  • Avoid feeding your parrot junk foods, like bread, French fries, and other human scraps. They’re not easily digestible and can clog up the digestive system.
  • Provide easily digestible foods. This includes fresh fruit, vegetables, pellets, and seeds.
  • Offer foods in different sizes. Incorporate various textures, such as roasted peanuts, peanut butter, sunflower seeds, and hulled seeds.
  • Clean out your parrot’s feeder to remove spoiled, wet, or moldy seeds and pellets. If a parrot’s food source isn’t regularly maintained, it can become unwell.

When feeding your parrot a well-balanced diet, monitor it for any changes to its weight, appearance, and feces. Low feather quality or constant pecking are signs of distress due to problems with food passing through the body. An avian vet should examine all behavioral and physical changes.