Problems Associated With Improper Hand-Feeding
April Romagnano, PhD, DVM,
Diplomate ABVP (Avian) Animal Health Clinic Jupiter, Florida
This overview covers basic pediatric history, husbandry, and
physical examination. Problems associated with improper hand-feeding are listed,
outlined, and explained.
Pediatric Patient Basics
Note the parent's health and breeding history, the condition of the siblings, and any problems during incubation and hatching. Evaluate the chick's diet, including preparation, feeding temperature, and the amount and frequency. Determine whether the bird's crop is empty for each feed, especially the first feed of the day (Figure 1). Assess environment, housing, and substrate for cleanliness, safety, and warmth. Inquire as to the behavior of the chick, especially its feeding response, and the color, consistency, and volume of its feces, urine, and urates.
A physical examination of the chick entails evaluating available weight charts for daily gain, and assessing overall appearance, proportions, and behavior. In neonates, this examination should be performed in a warm room with pre-warmed hands.
Because psittacine neonates are altricial, nourishment, warmth (93°F-98°F), food, and a safe place must be provided. Most abdominal organs can be seen through the neonates skin. The lungs and heart should be auscultated. Assess body mass by palpation of elbows, toes, and hips because keel muscle mass is a less reliable indicator of body weight in very young psittacine birds. Crops should be examined visually for size and color and carefully palpated for thickness, tone, burns, punctures, and the presence of foreign bodies. Crops should also be transilluminated to attempt to evaluate and describe their contents.
Skin should be evaluated for color, texture, hydration, and the presence of SC fat. Psittacine chicks should have beige-pink, warm, and supple skin. Dehydration causes a chick's skin to become dry and hyperemic (i.e., reddish and tacky). In juveniles, feathers should be examined for stress marks, color bars or shade changes, hemorrhage, and deformities of shafts and emerging feathers. Note that color bars or shade changes are relatively common in the initial feathers of commercially hand-fed baby birds, especially those hand-fed from day one. These color bars are most common in larger psittacine chicks with blue and red plumage.
The musculoskeletal system should be palpated and assessed for skeletal defects or trauma. Until weaning, cockatoo chicks sit back on their hocks and are balanced forward on their large abdomens; macaws prefer to lie down. Chicks have prominent abdomens due to a food-filled crop, proventriculus, ventriculus, and small intestine.
Beaks should be examined for malformations, but only when the bird's mouth is closed. Pump pads should be examined for wounds and the feeding response elicited. Generally, a healthy baby bird should elicit a vigorous feeding response when stimulated at the beak's lateral commissures.
The eyes and the periocular region should be examined for any abnormalities including lid defects, swelling, discharge, crusting, or blepharospasm. Normally a clear discharge is noted in the eyes when they are first opening. The eyes begin to open on days 14 to 28 for macaws, 10 to 21 for cockatoos, and 14 to 21 for Amazons. Nares and ears should be examined for discharge and aperture size or absence. The oral cavity should be examined for plaques, inflammation, or injuries.
Problems Related to Improper Hand-Feeding
Problems associated with improper hand-feeding are predominately management issues; however, their resolution often requires immediate medical and mechanical intervention. The main reason for this is the ubiquitous nature of crop stasis in the mismanaged or improperly hand-fed psittacine baby bird. The etiology of crop stasis is multifactorial. The crop will become static for numerous reasons but ultimately the patient becomes dehydrated and septic. Dehydration and sepsis are the most common causes of death in the hand-fed baby bird.
Lateral beak malformations are usually also a syringe feeding management problem. Hepatic lipidosis, gout, wine-colored urine, and hepatic hematomas are usually secondary to poor use of or inappropriate commercial diets.
Crop stasis is very common in neonate and juvenile birds; primary causes include infection, crop foreign bodies (FBs), atony, burns, dehydration of food in the crop, hypothermia, and food or an environment that is too cold or too hot. The most common cause of crop stasis is yeast or candidiasis. Secondary causes include distal gut stasis due to ileus, intestinal intussusception, bacterial or fungal infection, sepsis, dilatation, proven-tricular dilatation disease (FDD), Polyomavirus, gastrointestinal (GI) tract FBs, and renal or hepatic failure.
Medical and mechanical management are typically needed for the treatment of crop stasis. Diagnostics are very important, especially culture of the crop and cloaca, fecal gram stains, cytology, and blood work.
Further diagnostics, such as radiography, should be performed as needed without hesitation.
Fluids are key in the treatment of both crop and other GI tract stasis cases. Initially, oral fluids can rehydrate inspissated crop material and hasten its passage. If passage is not hastened, static crops should be flushed first thing in the morning and before each feed, as needed, for a few days. SC fluids are the treatment of choice for systemic rehydration and should be given in all cases of crop stasis regardless of severity. IV fluids are best in the severely dehydrated patient; placement of a right jugular IV catheter is preferred because they are safely maintained for days. If the crop is severely impacted, repeated flushing with warm saline may be required daily until GI motility is restored.
A crop bra is a simple form of mechanical management for the overstretched crop; reduction surgery may be necessary to facilitate emptying. Hypoproteinemia also may occur secondary to severe chronic crop stasis. In these cases, whole blood transfusions, and metoclopra-mide or cisapride, may be indicated as long as GI obstruction has been ruled out.
Chronic nonresponsive crop stasis may involve mural candidiasis. These cases are best diagnosed with biopsy and require long-term systemic anti-fungal and antibiotic treatment and acetic acid gavage. The most common clinical signs of crop stasis are a visibly oversized static crop and regurgita-tion. Although a manageable problem, crop stasis can be a fatal condition due to dehydration and sepsis and, therefore, demands immediate intervention and significant fluid therapy.
Regurgitation of small amounts of food post-feeding signals the need to reduce the frequency of feedings and begin introducing solid foods such as pellets, fruits, vegetables, and safe nut treats. Typically, as a bird grows, feeding volumes are increased, with the bird's weight and the frequency of feedings decreased. Therefore, a bird that is regurgitating during the day, well after the first feed, may need to have the frequency of feedings decreased. Regurgitation due to overfeeding can lead to aspiration pneumonia and is very serious. Repeated regurgi-tation in a chick, which is too young to be cut back in feeds or too young to wean, or regurgitation of large volumes, may indicate disease or mechanical blockage. Rule out FBs, crop or lower GI fungal or bacterial infection, gout, or FDD. Drugs such as trimethoprim sulfa, doxycycline, and nystatin can cause regurgitation, especially in macaw chicks. Have blood work and culture and sensitivities done and the chicks started on appropriate antibiotics and antifungals as needed. Antibiotics should be given parenterally versus orally.
Stunting occurs most commonly in the first 30 days of life. Affected birds have poor growth rates, low weight, an enlarged head relative to their body size, and abnormal feather growth including delayed emergence (on the body), misdirection (top of head), and feather stress bars.
Crop burns of the mucosa and skin occur secondary to feeding excessively hot hand-feeding formulas (>110°F). The most common cause of crop burns is the use of the microwave to heat premixed commercial formula. The microwave should never be used to heat hand-feeding formula. Crop burns must fistulate, and the surrounding tissue must be allowed time to necrose adequately. During this time, the bird should be fed smaller amounts more frequently to decrease the weight within the crop and increase the nutritional support to the bird, especially if leakage is occurring. The area should be kept clean, blood work should be run, and the bird put on parenteral antibiotics and antifungals, based on culture and sensitivities. Once necrotic delineation has occurred and healthy tissue can be differentiated from necrotic tissue, surgery can be safely and effectively performed. At surgery, the area around the fistula should be debrided and the edges of the tissues separated and freshened. The wound should be closed in two layersthe crop layer first, followed by the skin layer. Minor crop burns may resolve without fistulation and may not require surgery.
Esophageal or pharyngeal punctures can occur secondary to syringe or tube feeding. They are most common in vigorously pumping birds such as macaws. Esophageal punctures usually occur midway between the pharynx and the thoracic inlet in the most cranial aspect of the crop. Pharyngeal punctures usually occur in the caudal aspect of the pharynx slightly caudal to the right of the glottis. If such a puncture occurs, emergency surgery is needed to remove SC-deposited food, place a Penrose drain, and begin flushing of the wound (Figure 2). Post-puncture birds should be tube/gavage fed for some time so food does not come in contact with the puncture wound during healing. Chicks should be started on antibiotics and antifungals as needed.
Hepatic lipidosis occurs secondary to overfeeding, or individual susceptibility, primarily in hand-fed umbrella and moluccan cockatoos. It occurs less commonly in blue-and-gold macaws and occasionally in other species. Affected chicks have severely enlarged livers that are visible through the skin, enlarged abdomens, or are pale and dyspneic. These birds need to have their intake per feeding reduced and their frequency of feedings increased immediately to help decrease the dyspnea. Their dietary fat content needs to be evaluated and reduced, and they need to be started on lactulose and milk thistle.
Gout, a clinical sign, occurs secondary to severe renal disease. In juvenile macaws, gout is thought to occur secondary to excess vitamin D3 and calcium in the diet. In cockatiels and blue and gold macaws, a genetic predisposition is suspected. Affected chicks should be started on aggressive fluid therapy and allopurinol and given more appropriate diets.
Hepatic hematomas are suspected to be secondary to rough handling/trauma or possibly dietary deficiencies. Most reports have been
in macaws, where the etiology is unknown, and the syndrome occurred on homemade hand-feeding formulas. Affected chicks should be started on vitamin K, and given transfusions as needed.
Beak malformations may occur in baby birds; the three most common are lateral deviation of the maxilla (Figure 3), mandibular compression, and prognathism. Right lateral deviations of the maxilla are believed to occur secondary to improper syringe feeding. Lateral deviation of the maxilla and mandibular compression are most common in macaw chicks; prognathism is most common in cockatoos. While chicks are young and beaks are pliable, physical therapy and trimming is indicated several times a day. After calcification, frequent trimming, acrylic implants, or extensions are often needed to correct the beak malformations.
Problems associated with improper hand-feeding are predominately management issues. Resolution requires immediate intervention. The best way to successfully hand-raise healthy baby birds is to master proper hand-feeding and husbandry techniques.
Clubb S: Psittacine pediatric husbandry and medicine, in Altman RB, Clubb SL, Dorrestein GM, Quesenberry K (eds): Avian Medicine ami Surgery. Philadelphia, WB Saunders, 1997, 73-95.
Romagnano A: Alleviation of maldigestion, hypoprotein-emia in palm cockatoo neonates achieved through enhanced diet. AAV Newsletter and Clinical Forum: 9, Dec 1997-Feb 1998.