Clinical Case Challenge
Flight Trouble: To Trim or Not to Trim
Clinical Case Challenge: Schatzi (Cockatiel)
Shatzi, an 8-year-old male cockatiel, presented to his referring veterinarian with a recent history of lethargy, watery droppings and decreased appetite. According to the owner, the bird had recently been taken into a local pet store for a nail trim. The bird ate a varied diet including some pellets, nutriberries, vegetables, and fruit. Physical examination revealed that the bird was bright, alert, and responsive.
Fecal examinations including Gram’s stain and wet mount were within normal limits. Blood work was submitted and revealed elevated blood glucose (420 mg/dL; reference, 180-350 mg/dL), AST (617 U/L; reference, 20-350 U/L) and CPK (1327 U/L; reference, 50-400 U/L). Radiographs were obtained (Figures 2 and 3). The rDVM submitted samples for Chlamydia testing and started the cockatiel on azithromycin while awaiting results of diagnostic testing.
Based on results of blood work and radiographs, what are your differentials? What do you recommend as the next step?
Whole Body Ventrodorsal and Lateral Radiographic Projections
Shatzi presented to the Foster Hospital for Small Animals at Cummings Veterinary Medical Center at Tufts University for evaluation when the owner felt he wasn’t responding to antibiotic therapy. The referring veterinarian was astute to consider chlamydia as a differential since the bird had recently been to a pet store and was exposed to birds with unknown disease status. Fortunately, Shatzi’s chlamydia tests were negative, and blood work and radiographs were not suggestive of infectious disease. During Shatzi’s visit(s) to Foster Hospital, the Zoological Companion Animal Medicine team recognized that he was unable to fly, which was unusual given he was a flighted bird who flew whenever given the chance. Upon closer inspection, it was noted the bird’s wings were trimmed. After further discussion with the owner it became apparent the bird’s wings had likely been trimmed during a recent grooming visit at a local pet store; however, the owner was not aware this had happened. Since the grooming visit, the owner had noticed that Shatzi was lethargic and had been experiencing watery stools. Upon further questioning, the ZCAM team suspected that the elevated AST and CPK (which can be consistent with muscle enzyme elevation) were caused by Shatzi attempting to fly and repeatedly crashing to the ground. In addition, the veterinary team suspected the watery droppings and elevated blood glucose were consistent with a stress response (diabetes mellitus, while rare in birds, is usually associated with substantially higher glucose elevations than noted in this case). Since radiographs and CBC were unremarkable, it was recommended that while Shatzi adjusted to his wing trim the antibiotics would be discontinued, and the owner would provide a padded environment. Shatzi has recovered well. Through astute observation, interpretation of the lab test results, physical examination and questioning of the owner, the ZCAM veterinarian was able to diagnose and associate the side effects with Shatzi’s recent wing trimming.
Although wing trimming has traditionally been considered a ‘routine procedure’; there are potential risks, which need to be considered. Improper wing trims have been associated with feather picking, traumatic keel injuries, phobias, and even death. Many of the resulting problems can take weeks or months to develop and wing trim may not be suspected as the cause.
Wing trimming in bird:
Flight in birds
It is important to understand the function of the feathers of the wing to provide an appropriate trim.The wing can provide lift and thrust for the bird, much like the propeller and wings of an airplane. The four outermost primary feathers (primaries number 10-6) are primarily responsible for thrust power. The inner wing, along with shoulder muscles, provides lift. The inner primary feathers (primaries number 5–1), secondary feathers, and tertiary feathers also help to provide lift. Different types of wing feather trims provide varying results, depending on the body type of the bird. Clipping only the outer flight feathers will result in a reduction of thrust, while clipping the inner primary feathers reduces lift. Unilateral or asymmetrical clipping of the feathers results in an imbalanced delivery of lift or thrust.
When to trim and when to avoid trimming:
Many owners wish to have free-flighted birds in their home and as seen with Shatzi, trimming the wings led to an inability to fly. Flying is certainly the best exercise for birds and leads to improved muscle tone and cardiac health. However, any bird that is not trimmed is potentially ready to engage in free flight at any time. This increases the chance that the bird may be startled and fly into a predator’s grasp or onto a hot kitchen stove. Owners, who refuse wing trimming ,should be willing to assume the risks associated with housing a flighted bird. Although an owner assumes their bird would never fly away, accidents happen.
A young bird should not be trimmed before it is allowed to fledge. Ideally, weaned birds should be allowed to take short flights to ‘get used’ to flying and improve coordination. Most reputable breeders are aware of this and allow the bird to fledge before giving a conservative trim to avoid escapes. Gradual is best, and the trim can be modified during the first veterinary visits for best results.
Goals of wing clipping and types of trims
Wing clipping is most often used to prevent escape and to control mobility. Trimmed birds rely more on their owners than non-trimmed birds for transportation, and behavioral problems can be improved by limiting mobility in some instances. Cosmetic appearance after the trim is important when trimming display birds and to some owners.
Care must be taken to avoid causing the avian patient injury during handling. Excessive restraint may result in a fearful patient and create behavior problems at home. Trimming feathers too drastically can also cause a bird to be more prone to falling and result in injury.
There are many opinions on how to trim wings.
- Unilateral wing trims were recommended in the past but have now been found to be unacceptable as they can result in injury.
- A bilateral and symmetric wing trim is best.
- In a ‘cosmetic trim’, the outer 2-3 remiges are not cut while several are cut behind these to result in an aesthetically pleasing trim. If an owner prefers a ‘cosmetic trim’, advise them that it is possible for the bird to damage the outer 2-3 remiges that are left behind. If an owner has no preference, taking these outer remiges may be a safer alternative.
Tips on Trimming a Birds Wings
- When performing trims, carefully extend the wing, never restraining the wing by the tip to avoid iatrogenic humeral fractures.
- Use blunt tip scissors with rounded edges and carefully identify each shaft of the primary wing feather at its base.
- Cut the feather at the base, where it is just a bare quill, taking care to not cut the overlying covert feathers. Since each individual feather is identified before clipping, there is no chance of inadvertently cutting a blood feather, an active, growing feather with a blood supply. Blood feathers are easy to identify by its thickened, soft, purplish shaft and should never be cut. Additionally, if a blood feather is seen, a non-trimmed feather should be left on either side of it to avoid injury to the exposed feather. Using this type of trim, varying numbers of primary feathers are taken, depending on the body type of the bird. Most often, just five feathers can be taken and allow the bird to gently glide to the ground. Strong flyers or light-bodied birds (such as cockatiels and budgies) may need the outer seven primary feathers clipped on each wing (I have had to trim all 10 primaries on some determined cockatiels!).
- If possible, test-fly the bird after removing five feathers to make sure that it can glide to the ground, and not gain any lift or maintain horizontal flight for any length. It’s better to be conservative in the amount of feathers clipped at first and have the owner return with the bird for additional clipping, as necessary.
- Both wings should be clipped symmetrically.
- Trim only primary feathers. Heavier bodied birds such as Amazon parrots or African greys may need only 2-3 feathers trimmed in this manner.
Alternatively, just the last inch or two of the outer primary feathers may be trimmed. With this trim, lift is reduced gradually. This is a nice trim to use on heavy-bodied birds or young birds after they have fledged and before receiving a more aggressive trim. Avoid trimming the feather at mid-shaft level. The edges of the remaining feathers are just the right length to poke into the side of the bird’s body and cause discomfort that can lead to feather picking and mutilation
- Cummings School