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96 Hand-Rearing Birds

Angel Wing
Waterfowl chicks should be watched carefully for development of angel wing, a condition thought to
be nutritionally based. In this condition, the flight feathers at the wingtip flip up and out, giving the
appearance that suggests its name. It is also referred to as airplane, reversed, slipped, or sword wing.
There are several dietary factors that may contribute to the malady. Diets high in sulfur‐producing
amino acids, deficiency of vitamin E and manganese, plus high protein for some species, have been
cited as factors (Ritchie et al. 1994). A diet high in carbohydrates and sugar, such as when young
waterfowl are fed white bread, also contributes to the problem. The physical problem begins when
the weight of the flight feathers and gravity pulls the carpal joint down and out. Angel wing can be
corrected if intercepted early. Wrapping the wing to itself in a natural position for a few days may
correct the problem. Wraps must not be left on longer than a few days in consideration of the young
birds’ rapid growth rate. Be careful to apply wraps such that they do not damage the growing blood
feathers. Untreated, the wing will be permanently deformed and the bird will not be releasable.

Lead Poisoning
Lead poisoning is a serious and unfortunately common problem in waterfowl coming into reha-
bilitation. In the United States alone it was estimated that 2.4 million waterfowl die yearly from
lead poisoning (Ritchie et al. 1994). Birds come into contact with lead in the wild in various ways,
including swallowing lead sinkers commonly used for fishing, lead shot from bullets, or ingestion
of mine wastes. The possibility of lead poisoning should be considered with all swans and, to a
lesser degree, geese.
Birds admitted with lead poisoning may have a variety of symptoms that include low weight,
weakness, inability to walk or use legs well, wing droop, and the signature grass‐green feces. Often
feathers on the chest and crop area may be soiled due to vomiting. Patients with lead poisoning also
will be generally lethargic, anemic, and dehydrated. Not all symptoms need to be present and will
vary with the patient, species, amount of toxicity, and source of lead. Many will be unable to digest
food. Vomiting is common. In these cases, fluids should be given subcutaneously. Oral tube‐feeding
in small amounts can be attempted, keeping in mind that aspiration may result if the bird regurgi-
tates the oral diet. If the crop empties and the bird is defecating, a more liquid diet can be fed (see
the section on Emaciation Diet for Debilitated Waterfowl later in this chapter). Offer the bird water,
but do not allow it to eat grain or solid food until the digestive system is functioning normally.
Blood testing and diagnostic imaging play an important role in the diagnosis of lead poisoning,
and early diagnosis and treatment is imperative. If metallic densities are observed on x‐ray, gastric
lavage or endoscopic removal of metal pieces (Ritchie et al. 1994) may be required. Consult an
avian veterinarian in lead poisoning cases. Calcium disodium versenate or dimercaptosuccinic
acid (DMSA) are often used to chelate lead from the blood stream.
Many states have banned the use of lead for waterfowl hunting, but lead shot is often used in
small and large game hunting as well as fishing. Lead does not degrade in the environment. Swans,
in particular, encounter lead pellets when water levels are low and they eat material from the bot-
tom of lakes or streams. Conservation groups often have material available on nontoxic alterna-
tives to lead sinkers and lead shot that may be helpful to create an awareness of the problem.

Botulism
Young waterfowl may present with botulism. Clostridium botulinum grows in anaerobic condi-
tions, when bodies of water become warm and have poor flow. This bacterium produces a toxin
that paralyzes the neuromuscular junctions of affected animals. Birds are exposed when they eat