Budgies have unique digestive systems. Because budgies don’t have teeth, their digestive tract is adapted to pulverize food and absorb the nutrients their bodies need to function.
Unfortunately, budgies are prone to several digestive problems. If their digestive tract is affected by an infection, virus, disease, or slow-moving crop, it struggles to function as effectively as it should.
Digestive problems cause weight loss, malnutrition, poor feather quality, chronic regurgitation, and the inability to digest food.
Young budgies with poor immune systems are most at risk of digestive problems, so owners must monitor their pet budgies while growing and developing.
How Does a Budgie’s Digestive System Work?
Budgies have a digestive tract that’s not like that of other animals.
Unlike mammals, they have beaks instead of teeth to make them aerodynamic. However, this means they can’t chew their food into small pieces.
Instead, they use several organs for digestion. Each plays a vital part in the process, helping budgies pulverize the hard-to-digest foods they eat.
Because budgies have to search for food in the wild, which is limited in some areas, their digestive systems are designed to obtain the most from the foods they find. This helps protect them from starvation and predators who know to strike when they’re preoccupied with eating.
Budgies use the following organs to digest their food:
Mouth and Tongue
Budgies begin by scooping food into their mouths and pushing it into the digestive tract with their tongues. They also use their tongues to keep live insects in place, like grubs and mealworms.
Similarly, the pharynx helps budgies swallow food between the mouth and esophagus.
Once a budgie swallows its food, it travels down the esophagus – a large tube located on the right side of the neck – to reach its stomach.
The neck also extends, allowing budgies to swallow lots of food at once. This is vital for wild budgies, as they don’t always know where their next meal will come from.
The crop is a muscular pouch in the neck that works as a storage facility for food.
Budgies fill themselves up on more food than they can digest. As a result, food remains in the crop until it can be digested later.
Also known as the glandular stomach, the proventriculus is the first part of the two-chambered stomach. This rod-shaped organ secretes an acid that breaks down food.
The gizzard is the second part of the two-chambered stomach, consisting of tough muscles that grind food into smaller pieces.
Many budgies consume sand, grit, and small pebbles when picking up food, which they use to pulverize it.
Once the food’s been broken down, the nutrients are absorbed into the small intestine. The rest of the food moves further down the digestive system.
Leftover food moves into the large intestine, where it reabsorbs water. However, the large intestine isn’t as vital to the digestive process as the other organs.
The rectum is a short intestine tube at the end that connects the organ to the cloaca. No digestion or food absorption occurs here, but it allows undigested food to pass into the cloaca.
The cloaca appears at the end of the digestive tract and is a storage facility for waste from the digestive and urinary tract.
The waste appears as a white liquid with a dark center. Once a budgie is ready to release its waste, it exits the body through a sphincter at the base of the cloaca.
Common Budgie Digestive Problems
As described by VCA Hospitals, budgies become ill when they’re not cared for or fed properly. This is how some, although not all, digestive issues occur.
The most common budgie digestive problems include:
1/ Avian Gastric Yeast
Avian gastric yeast (megabacteria) is a disease that affects the gastrointestinal tract. It’s caused by yeast and occurs when budgies come into contact with infected food or an infected bird’s droppings.
The MSD Veterinary Manual describes how avian gastric yeast is common in smaller birds, including budgies. Birds with weakened immune systems are also affected.
The most common signs of avian gastric yeast include:
- Chronic weight loss
Droppings may also contain undigested seeds or pellets, which a vet will use to diagnose the condition.
The death rate ranges from 10 to 80%, depending on the species and the yeast strain. Stronger yeast strains are usually fatal, and even if a budgie recovers, relapses are common.
2/ Avian Polyomavirus
Avian polyomavirus (APV) causes disease in young birds. There are two forms of APV:
- Budgerigar fledgling disease
- Non-budgerigar polyoma infection
Both result in the death of pre-weaned neonates approximately 2-15 days after they’ve hatched.
Avian polyomavirus has a high mortality rate. For example, budgies less than 15 days old are believed to have a 100% mortality rate.
The virus causes feather lesions and papilloma (warts) in budgies.
Other common symptoms include:
- Lack of appetite
Crop stasis also occurs within 24-48 hours. Baby budgies that have died suddenly must be checked for APV, as asymptomatic birds can carry strains of the virus.
You’ll also need to kill strains of the virus by:
- Disinfecting the budgie’s cage
- Offering good ventilation
- Keeping beddings, toys, food, and water clean
3/ Sour Crop
Sour crop (crop impaction or crop stasis) is a term used to describe a crop infection.
It occurs when the crop empties too slowly or can’t empty due to an infection. The infection causes food contents in the crop to ferment and become sour.
Hand-reared budgies that are spoon or syringe-fed are more susceptible to sour crop than birds raised by their mothers. For example, an overly thick or hot and cold formula can lead to an infection.
Bacteria is the most common cause of sour crop, but yeast infections are also responsible. So are:
- Foreign objects
- Trauma and injuries
Thankfully, crop infections are less common than they used to be. It’s also not fatal if treated early enough, but it’s likely to cause long-term appetite and digestion problems if ignored for too long.
The main symptoms of sour crop include:
- A fluid-filled or distended crop
- Chronic regurgitation
- Foul odor
- Undigested food in droppings
- Visible distress
- Decreased appetite
- Lack of feeding response
4/ Candidiasis (Thrush)
Candidiasis, or thrush, is a common condition caused by the yeast Candida albicans – the same thrush-causing organism children get.
It’s normal for small numbers of thrush to be present in a budgie’s digestive tract, but it can develop into an illness under certain conditions.
Thrush is more common in young, unweaned budgies or birds on antibiotics because of their undeveloped immune systems. Similarly, antibiotics kill off beneficial bacteria in the digestive tract, allowing the Candida yeast to overgrow.
Candidiasis also affects malnourished budgies. However, the severity of the condition depends on the bird’s age and the health of its immune system.
The most common symptoms of thrush in budgies include:
- Regurgitation of food
- Lack of appetite
- General signs of illness
- A swollen mucus-filled crop
- White spots in the mouth
Thrush spreads through a contaminated environment. Good hygiene that involves disinfecting the cage, nest box, and utensils can help minimize the amount of Candida in the budgie’s environment.
5/ Proventricular Dilatation Disease (PDD)
More commonly known as macaw wasting disease, proventricular dilation disease (PDD) affects the nerves that supply a budgie’s gastrointestinal tract – particularly the proventriculus, which is the narrow glandular first region of the stomach between the crop and gizzard.
The disease stretches the stomach, preventing the muscles from aiding with digestion. As a result, nutrients from food and water can’t be absorbed or digested.
Symptoms of proventricular dilation disease include:
- An initial increase in appetite
- Chronic weight loss
- Head tremors
- Difficulty perching
- Leg paralysis
- Undigested food in the feces
- Smelly stools
An avian bornavirus is responsible for PDD, which infects budgies exposed to the feces of infected birds when sharing a cage. While outbreaks are uncommon, they’re often fatal.
Affected budgies must be isolated to prevent others from becoming affected.
6/ Pacheco’s Disease
Pacheco’s disease is caused by psittacine herpesvirus, resulting in liver inflammation and organ damage.
It’s highly contagious, transmitting through nasal discharge and contaminated feces. It also kills quickly, with budgies dying only a few days after contracting the disease.
Pacheco’s disease sometimes appears as papillomas – pink, cauliflower-like growths. They grow in the mouth and digestive tract, causing:
- Open-mouthed breathing
- Swallowing difficulties
- Loss of appetite
Papillomas also sometimes protrude from the vent and are visible when the affected budgie strains when pooping. Surgery is usually needed to remove the growths. Even if the surgery is successful, they may reoccur later on.
The disease damages several organs, including the spleen, liver, and kidneys. Your budgie may survive Pacheo’s disease, but it will likely develop internal papilloma, and the damage will also be permanent.
7/ Gastrointestinal Parasites
Budgies commonly suffer from gastrointestinal parasites, which cause various digestive issues. Parasites affecting budgies include:
Birds infected with giardia develop diarrhea and become itchy, violently attacking themselves as a result. This most commonly occurs under the wings.
Giardiasis occurs when protozoa – microscopic single-celled parasites, enter the intestines. Once this happens, giardiasis causes:
- Abnormally large droppings
- Inability to absorb nutrients
- Weight loss
- Poor feathering
- Excessive crying
Thankfully, giardiasis is easy to treat with oral medications.
Trichomoniasis is a protozoan infection that results in yellow-whiteish lesions in the mouth, throat lining, crop, and esophagus.
According to Birds & Exotics Veterinarian, it’s most commonly seen in budgies, where the condition is known as “canker.”
The condition results in increased salvation and regurgitation. Other clinical signs include:
- Vomiting and regurgitation
- White plaques in the crop and trachea
- A “fluffed up” appearance
- Green diarrhea
- Dyspnoea (difficulty breathing)
- Poor growth in young birds
Affected budgies also experience weight loss with increased appetite – budgies often select the smallest seeds to eat as it is easier and less painful.
Budgies develop the disease through direct mouth-to-mouth contact when exposed to contaminated food and water. However, some birds can become carriers, showing no signs of infection – even after years of harboring it.
If left untreated, trichomoniasis is fatal.
Roundworms occur in several forms and reside in a budgie’s digestive tract. Infection occurs when budgies eat roundworm eggs when they eat a host, like an insect.
Symptoms aren’t always apparent, meaning budgies shed roundworm eggs through their feces for a long time before becoming unwell.
Symptoms also vary depending on the type of roundworm infecting your budgie and the part of the body it lives. Ascarids most commonly affect budgies.
There are many signs of roundworm, but the most common include:
- Open-mouthed breathing
- Difficulty swallowing
- Weight loss
- Head shaking
- Eyelid spasms
- Masses on the legs and feet
Tapeworms are a class of flatworms that infect budgies and other birds. They’re slightly less common than other parasites but can still cause a problem.
Tapeworms live inside the lower gastrointestinal tract. While there, they steal nutrients from food and water, causing the bird to become malnourished and thin with poor-quality feathers.
Tapeworm symptoms are wide and varied, but the most common include:
- Loss of energy
- Abdominal thinness
- Intestinal obstruction
- Sudden changes in behavior
- Oily plumage
- Increased vocalization
- More droppings
- Gain of appetite
Not all budgies develop symptoms – at least not straight away. If you suspect your budgie has tapeworms, look for worms in its poop.
You’ll also need to get your budgie checked out. Only specialist avian veterinarians can diagnose tapeworms by looking for evidence of them in expelled feces.
You should use gloves to carefully scoop the fresh poop into a bag you can seal. Wash your hands thoroughly to prevent transmission.
Budgies can develop several digestive problems. While symptoms don’t always present themselves, monitoring your budgie’s health and behavior is important to stay on top of diseases and parasites.