Blood thiamine values in captive adult African lions (Panthera leo).

Heparinized whole-blood samples from 22 adult African lions (Panthera leo) fed diets considered nutritionally adequate in 10 American Zoo and Aquarium Association member zoos in North America were provided for this study. Blood thiamine values were estimated using a standard microbiological assay method. The mean +/- standard deviation for blood thiamine values was 249.3 +/- 43.5 nmol/L with a range in values from 160 to 350 nmol/L after exclusion of one outlier. There were no differences (P > 0.05) in the mean blood thiamine values of male and female lions, or of lions that were over and under 10 yr of age. This range (160 to 350 nmol/L) is proposed as a reasonable estimate of the expected range in blood thiamine values for captive adult African lions as currently fed in North American zoos.

Presumed primary thiamine deficiency in a young African lion (Panthera leo).

A 1-yr-old intact male African lion (Panthera leo) fed only beef muscle meat was evaluated for episodes of hypermetric ataxia, generalized weakness and tonic-clonic front limb movements. A hemogram, biochemical profile, blood lead, electrocardiogram, survey radiographs, and brain computed tomography were normal. Cerebral spinal fluid analyses suggested mild inflammation. Acetylcholine receptor antibody and serologic tests for all infectious agents tested were negative. Clinical signs resolved completely 9 days after instituting oral thiamine (3 mg/kg/day) and a completely nutritional diet. This lion's pretreatment thiamine blood value (11 nmol/L) was markedly lower than that of a healthy lion (191 nmol/L) and a proposed reference range for adult African lions (160-350 nmol/L). The lion remained clinically normal 2 yr later when his blood thiamine value was 340 nmol/L. African lions can develop clinical primary thiamine deficiency and may respond favorably when thiamine treatment and adequate diet are instituted prior to irreversible neuronal necrosis.