Elevated urinary cortisol in a timber wolf (Canis lupus): a result of social behaviour or adrenal pathology?

In a previously published report, a male timber wolf (Canis lupus) was iden tified as having significantly elevated urinary cortisol to creatinine rati os relative to other males in the pack. This second-ranking animal, whose s ocial status was being challenged, was involved in far more aggressive inte ractions than any other pack member. The wolf died 3 years later from gastr ic and splenic torsion. Necropsy revealed a unilateral adrenal tumour ident ified by histology and electron microscopy to be a cortical adenoma. This f inding is based on the presence of abundant lipid and no evidence of neuros ecretory granules. Whether the increased cortisol levels in this wolf were the result of social stress, as originally suggested, the tumour, or both i s uncertain.