title: The role of lead in a syndrome of clenched claw paralysis and leg paresis in Swamp Harriers (Circus approximans).
abstract: We investigated the hypothesis that lead poisoning was the cause of the clinical syndrome of clenched feet paralysis and leg paresis in wild raptors. Swamp Harriers (Circus approximans) are one of three extant native raptor species in New Zealand. Harriers with the syndrome were found to have statistically significantly higher blood lead concentrations than those without clenched feet (t-test; t=-4.06, df=5, P=0.01). However, elevated blood lead concentrations were also present in 60% of wild harriers without the clinical syndrome of clenched feet paralysis and leg paresis. There were features of the response to chelation treatment, electroneurodiagnostics, and pathology that were inconsistent with lead poisoning as reported in other birds of prey. We conclude that lead may be a factor in the expression of this clinical syndrome of clenched claw paralysis but that other factors not identified in our study play a role in the expression of the disease.
authors.affiliation: New Zealand Wildlife Health Centre, Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: McLelland
authors.forename: Brett D
authors.initials: BD
authors.lastname: Gartrell
authors.forename: Kerri J
authors.initials: KJ
authors.lastname: Morgan
authors.forename: Wendi D
authors.initials: WD
authors.lastname: Roe
authors.forename: Craig B
authors.initials: CB
authors.lastname: Johnson
mesh_terms: D000818:Animals; D000835:Animals, Wild; D001715:Bird Diseases / Q000139:chemically induced / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D006724:Hoof and Claw / Q000473:pathology; D007854:Lead / Q000032:analysis; D007855:Lead Poisoning / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary*; D008297:Male; D009520:New Zealand; D010243:Paralysis / Q000139:chemically induced / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary; D020304:Raptors; D013045:Species Specificity
chemical_list: D007854:Lead