Article by: Jeannine Miesle, M.A., M.Ed
Main Article: Hand-raised or Parent-raised: Which Is Better For The Birds? by Jeannine Miesle M.A., M.Ed.
Physical Illnesses and Conditions Brought About by Improper Hand-feeding
16.1 Beak Deformities from Poor Hand-feeding Techniques
16.1.1 Maxillary Brachygnathism
16.1.2 Mandibular Prognathism
16.1.3 Scissors Beak
16.2. Damage to the Crop
16.2.1 Crop Stasis—a Case Study
16.2.2 Crop Burns
16.2.3 Trauma to the Crop Caused by Improper Handling
Image 17: This breeder is correctly hand-feeding a chick; however, one can see how easy it would be for someone not experienced to cause beak trauma (image courtesy Thaddeus Tumanen; used with permission).
16.1 Beak Deformities from Poor Hand-feeding Techniques
Many people think they can hand-raise baby birds when they have had no experience or education from an experienced breeder on how to do this. They unintentionally harm the bird’s mouth, feet, and beak, and sometimes the deformities cannot be undone.
Hand-feeding techniques are a common cause of beak deformities. Brian Speer explains this:: “Incorrect incubation and/or hand feeding practices may be the more common causative factors, but the specifics of what those deficits may be are poorly understood. It is theorized by many that bruising of the rictal phalanges (the upper rictal area is where the beak meets the cere, and the lower rictal phalanges are where the under part of the beak meets the skin.) occurs during hand-feeding. There are feather bristles in these areas; damage to one side or the other leads to uneven growth, and most likely results in a scissoring deformity. Hand-feeding technique flaws resulting in bruising of the rictal phalanges, incubation flaws, genetic etiologies, sub-clinical malnutrition, infectious sinusitis, trauma and viral disease have all been suggested as possible contributing causes. Corrective procedures in young birds are designed to alter the forces that direct the rostral growth of the rhinotheca.” 10
Image 18: Anatomy of the beak (image courtesy PetEducation.com; used with permission).
- The rhinotheca is the outer surface of the beak. It is composed of a horny layer of keratin which covers the beak.
- The rhampotheca is the layer of keratin on the maxilla (upper beak). The gnathotheca is the layer on the mandible (lower beak).
- The commissure is the soft tissue at the back of the beak where the two parts meet. It is composed of soft tissue for the opening and closing of the beak to take place.
- The rictal phalanges are the areas of the beak just below the commissure where the maxilla and mandible meet. There are usually bristle feathers in that area.
- Tomia: cutting edges of the beak
- Malocclusion (poor closure of the beak) is a consequence of trauma due to damage to the germinative layer of the beak, improper hand feeding, poor nutrition, or heredity. The practitioner may be able to use composite or acrylic materials to shape the beak properly and encourage normal growth following trauma. 7
16.1.1 Maxillary Brachygnathism
This is one condition that is sometimes caused by improper hand-feeding. With it, the maxilla extends well past the mandible. It is usually a congenital condition, and cockatoos are most frequently affected species. It is most often caused by trauma which damages the germinal epithelium of the beak. “Young birds with this condition are often more receptive to having this condition corrected since their beaks are more pliable than adults’ beaks. Wiring or prostheses may be used to gently put the beak back in alignment.” 7
Image 19: Maxillary brachygnathism, or overgrown beak, in an Amazon (image courtesy Dan Razdik; used with permission).
Image 20: Mandibular prognathism, or maxilla inside mandible, in a cockatoo (image courtesy Melanie Canatella; used with permission)
16.1.2 Mandibular Prognathism
This is another recognized pediatric condition sometimes caused by improper hand feeding. With this, the maxilla lies inside of the mandible, and it is most often observed in cockatoos. One technique which has been used to correction this deformity has been the application of acrylic to the maxilla. This technique “functionally extends the maxilla, making it more challenging for it to be placed inside of the mandible, and guides occlusion (closure of the beak) properly. Typically, when the acrylic loosens and comes off in 1-2 weeks, the problem is corrected.” 10
16.1.3 Scissors Beak
Young, hand-fed cockatoos and macaws are frequently afflicted with scissors beak. “Scissors beak deformities are characterized by a bending of the upper beak rhinothecal keratin and/or bone to one side to varying degrees, with the resultant overgrowth of the opposing lower gnathotheca. As force vectors are applied during the bird’s growth and regular use of its beak, this deformity usually will become progressive, ultimately generating a ‘scissors’ effect.’ In addition, secondary deformities of the occlusal ledge of the rhinothecal keratin may develop.” 4 “The occlusal edge is the underside of the maxilla or upper beak where it meets the mandible or lower beak; it acts as an anvil by which the bird can crush nuts and seeds and other foods.” (R. Dahlhausen, personal communication) “This deformity carries a significant impact on the salability and potential breeding performance of the birds.” 10
Due to the stress put on the bird from trying to eat and perform the usual beak grinding, an increase in the fear-based behavioral problems will occur. The owner should be encouraged to consider having these conditions surgically corrected. “The corrective techniques that are available today are vastly superior than in the past and are worth considering when one takes into account the quality of life and long-life expectancies of the larger species.” 10
Scissors-beak is most commonly seen in macaws, and the trans-sinus pinning technique as well as others are being used to correct this deformity. Application of corrective techniques for both conditions have been limited to use in young birds since they have not been successful in correcting these deformities in adult birds. 10 In adults, the beaks must be constantly trimmed and reshaped in order for the bird to be able to eat.
Images 21 and 22: Scissors beak in a cockatiel (image courtesy Dr. Maria Angela Panelli Marchio; used with permission).
16.2. Damage to the Crop
16.2.1 Crop Stasis—a Case Study
A twelve-week-old blue and gold macaw was presented with a history of crop stasis of 24 hours duration. The bird had been purchased from a breeder in Georgia at the age of 6 weeks. The baby had been parent-fed for the first four weeks of its life and then switched to a commercial hand-feeding formula. On physical examination, the bird was bright, alert, and responsive and had a brisk feeding response. It was well grown for its age and was completely feathered. However, the crop was still full from the feeding the night before and the bird was mildly dehydrated, slightly thin, and there were many stress bars on the growing feathers. Gram’s stains of the crop showed budding yeasts and Gram-negative rod-shaped bacteria. “A Gram stain of a cloaca swab showed moderate numbers of Gram positive coccoid and large rod-shaped bacteria.” 8 The white blood cell count was normal, but radiographs showed a distended proventriculus. A fecal float and direct smear were negative for parasites. 8
This was a case of crop stasis that in nestlings can have any number of causes, “ranging from improper husbandry to systemic infectious diseases.” 8 It is not normal for fledglings to develop crop stasis, and it appeared that this bird had been under a great deal of stress for several days, as evidenced by the number of the stress bars on his newly formed feathers. 8 The bird had not been digesting its food very well, and it resulted in an overgrowth of yeasts and bacteria in the crop. Some birds will develop distention of the proventriculus, but that also might be a sign of a primary disease of the gastrointestinal tract which affects motility. 8
16.2.2 Crop Burns
Crop burns that lead to fistulation normally occur in unweaned psittacines fed formulas that are too hot. Microwaving formula is often the cause due to uneven heating. Damage to the crop may interfere with crop motility. Mild burns may cause inflammation and edema that may resolve. Extreme heat may cause a fistula (a hole leading to the outside) into subcutaneous space or a full-thickness fistula. 1
Birds will present with voracious appetite and weight loss. On physical examination, moistened feathers are noted in the area of the crop; normally a scab is present. It is recommended to wait 3-‐5 days in the case of full-thickness fistula. The tissue needs time to show the extent of the damage, otherwise repair may fail. Extensive burns require removal of an extensive area of the crop; prognosis may be poor due to lack of normal function. 1
Images 23. African Grey: Crop burn from hand-feeding with formula that was too hot from being heated in a microwave. A large fistula was present and needed to be repaired surgically (image courtesy Aswathy Sathi; used with permission).
When the crop is burned or traumatized, there may be loss of significant portions of tissue. In some birds there will be a true fistula with food dropping out. In more acute burns, it may be difficult to distinguish viable from devitalized tissues. In these cases it is best to wait 3-5 days for a line of demarcation between necrotic and viable tissue to develop. The wound edges should be debrided until the skin can be separated from the crop wall. The skin and crop are sutured closed as separate structures. Placing a feeding tube through the crop will help identify the lumen. “In cases where there is significant loss of crop tissue, it is best to maintain the longitudinal integrity of the esophagus (crop) as there is a higher likelihood of stricture formation with resection and anastomosis.” 1,3 (Anastomosis a connection made surgically between adjacent blood vessels, parts of the intestine, or other channels of the body, or the operation in which this is constructed (Wikipedia).
16.2.3 Trauma to the Crop Caused by Improper Handling
Laceration of the esophagus can occur following the use of a rigid feeding tube. 7 The ingluvies refers to the crop, an outpouching and storage area in the esophagus that is often full and protruding, making it susceptible to trauma. It may also be the site where a foreign body has lodged. 1
Image 24: Full-thickness crop burn in an umbrella cockatoo. The scab is being pulled away to reveal the large fistula from which formula is leaking out (image courtesy Scott McDonald; used with permission).
Image 25: The umbrella cockatoo after crop-burn repair. The crop and skin are closed in separate layers after unhealthy tissue from wound edges is trimmed away (image courtesy Scott McDonald; used with permission). http://scottemcdonald.com/pdfs/Crop%20Disorders.pdf
