Clinical signs and diagnosis of thiamine deficiency in juvenile goshawks (Accipiter gentilis)

Between 2002 and 2006, a large number of juvenile northern goshawks ( Accipiter gentilis ) with central nervous signs were examined. They were aged between 45 and 55 days and had been fed on frozen and thawed day-old chicks. High-performance liquid chromatography showed that the birds had whole blood thiamine levels between 2·2 and 6·0 μg/l; the concentrations of other blood constituents were within their reference ranges. Treatment with thiamine hydrochloride rapidly resolved the clinical signs. Measurements of the concentration of thiamine in 22 free-ranging and captive goshawks showed that they ranged from 45·1 to 200 μg/l.