Evaluation and treatment of lead toxicosis in rehabilitated avian species: 95 cases (2014-2023).

Objective: To evaluate avian patients presented to a wildlife rehabilitation facility with confirmed lead toxicity for clinical signs associated with blood lead level groups, efficacy of subcutaneous chelation therapy with calcium disodium EDTA, and case outcome based on presenting blood lead levels.

Methods: A retrospective record review of 95 avian cases representing 19 species treated for lead toxicosis from a wildlife rehabilitation center in Wisconsin between 2014 and 2023 was conducted. Data were evaluated for presenting complaints, clinical signs, radiographic findings, chelation therapy protocol, clinical pathology data, and case outcome.

Results: A low lead level of < 20 µg/dL was the most commonly diagnosed level in avian patients. The presence of neurologic disease was found most commonly in birds with higher blood lead levels, whereas poor body condition, trauma, and anemia were most common in birds with low lead levels. Bald eagles (Haliaeetus leucocephalus) and tundra swans (Cygnus columbianus) were the most prevalent species presented. All methods of chelation therapy evaluated resulted in a reduction of blood lead levels. Patients with intake blood lead levels > 60 µg/dL were more likely to die or be euthanized while in care.

Conclusions: A bird with a blood lead level > 60 µg/dL is more likely to present with neurologic disease and have a poor case outcome. Diluted calcium disodium EDTA was clinically effective when administered SC.

Clinical Relevance: Initial blood lead level, in conjunction with species, clinical signs, and radiographic changes, can help guide clinical decision-making for avian patients with lead toxicosis.