THE MERCK VETERINARY MANUAL
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Pediatric Diseases of Pet Birds

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Pediatric diseases in psittacine chicks can present diagnostic challenges. Intensive hand-rearing methods often create problems, as do husbandry errors. Proper nursery management, incubation, and production techniques are fundamental to the prevention of pediatric problems in parrot chicks. Captive breeding has greatly increased the frequency of pediatric diseases. Birds that would have perished due to illness in the wild can often be treated in captivity. Unfortunately, captive breeding has also increased the frequency of diseases related to genetic manipulation (eg, breeding for colors) and developmental problems created with artificial incubation and hand-feeding.

Certain viral diseases, notably polyomavirus and circovirus, are most often seen in pediatric psittacines (see Viral Diseases of Pet Birds).

An ingluviotomy is performed in order to gain access to the mucosal surface and lumen of the crop, proventriculus, or ventriculus. Removal of a foreign body, such as a feeding tube, is the most common indication for this procedure in pediatric birds. In larger or older birds, a rigid endoscope may be necessary to visualize and extract upper GI foreign bodies. The endoscope may be used either orally or through an ingluviotomy incision, depending on the accessibility of the foreign body.

Damage to the crop is most often from thermal burns caused by improperly heated hand-feeding formula. The severity of the burn and the bird's reaction vary greatly. Some birds become ill from the tissue damage and may develop endotoxemia and die despite intensive supportive care. These birds are not surgical candidates, until/unless they survive the initial illness. Surgery should be delayed until the burned area has begun to granulate, allowing the development of a healthy tissue bed for surgical reconstruction.

Other birds with crop burns remain totally asymptomatic and are presented by their owners when either food or a hole is noticed in the area of the crop. In this case, the crop has already fistulated, creating a demarcation between healthy and necrotic tissue. This decreases the quantity of tissue that must be resected. Supportive care is provided until surgery can be performed.

The liver in neonates is typically larger relative to the total body weight than in adult birds, so some degree of hepatomegaly is normal in chicks. However, neonates with hepatic lipidosis typically have the following characteristics: 1) they are usually still being hand fed, often with a commercial formula to which the owners have added peanut butter, oil, or some other high-fat food, and 2) they are usually heavy for their age and exhibit severe respiratory distress. These birds must be handled gently and minimally. Cool oxygenation is the best first step. They have virtually no lung and air sac capacity and the stress of feeding and breathing at the same time has exceeded their oxygen reserves. Drastically reducing the quantity of crop food per feeding, adjusting the content of the formula, and adding lactulose to the formula are the general nutritional changes required. Parenteral fluid supplementation, when tolerated, helps keep the initially hyperthermic bird hydrated and detoxify the body, as the liver is generally not functioning adequately. When possible, blood samples should be obtained to check for concurrent infection or other diseases.

Hereditary, congenital, and husbandry issues may affect young birds. Often problems are noted shortly after purchase. This may be due to husbandry issues, such as new owners who are inexperienced at hand-feeding. Inappropriate quantities of hand-feeding formula and incorrect temperature or nutritional content can cause stunting, reduced feeding response, or GI stasis.

Birds that are purchased soon after arriving at the pet store are often mistakenly labeled as “weaned.” In nature, these birds would be eating partially on their own but still receiving supplementation from their parents. When such a bird is sold to an uninformed owner, it usually takes a few days to a few weeks for the bird's insufficient food intake to create noticeable debilitation and weakness. These birds may also have underlying problems, eg, decreased hepatic function or decreased immunocompetence. With supportive care, some of these birds will survive, but many will not.

The term splay leg is a catch-all for deformities of the legs in young birds. Often there are laxities of the ligaments of the stifle, and/or angular deformities of the femur, tibiotarsus, and tarsometatarsus. Etiologies are poorly documented, but include nutritional deficiencies (consistent with those of metabolic bone disease, see Nutritional Diseases of Pet Birds) and insufficient support or substrate in the enclosure. Various methods of external coaptation have been devised and are most successful when the bird is young. Surgery can also be employed.

This condition commonly occurs in several birds from the same clutch. If detected early, the mandible may be manually manipulated to avoid prosthesis application or trans-sinus pinning. The prostheses can be cumbersome, painful, and often need to be reapplied. Trans-sinus pinning is a more recent and more reliable method of correction, but does have some risk.

This is fairly common in neonates, often affecting >1 digit. An annular band of fibrous tissue forms at a joint of the digit, impeding circulation. The etiology is unknown, although both excessively low and high humidity and septicemia have been proposed. When detected early, debridement of the annular band and application of a moist dressing is often effective. Creating small longitudinal cuts on the medial and lateral surfaces to allow for swelling and circulation, and suturing of the digit over the incised area, followed by a dressing, are sometimes needed. If circulation loss is severe and necrosis is apparent, amputation may be necessary.

This syndrome is most commonly seen in cockatiels, and is often noted in several members of the same clutch. The condition is usually bilateral. The eyelids, if present, are generally normal in conformation but greatly reduced in length, leading to small to nonexistent palpebral fissures. If the palpebral fissure is sufficient to allow functional vision, no correction is needed or recommended. Extension of the palpebral fissure by conjunctival eversion can be performed with modest success when the palpebral aperture is absent or reduced and functional vision is compromised.

This syndrome can appear in clutches, most commonly in cockatiels. Bordetella sp has been implicated in the sinusitis and secondary osteomyelitis associated with this disease.

This condition is prevalent in African Grey parrots. Incomplete communication between the nares, infraorbital sinus, and the choana occurs, causing increased mucus accumulation and possible infection in the sinuses and nares. Incomplete or absent communication between the infraorbital sinus and the oropharynx must be surgically repaired. Communication is created between the structures, and a means of maintaining the aperture is provided while the area heals.

Last full review/revision July 2011 by Teresa L. Lightfoot, DVM, DABVP (Avian)

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