Noninvasive endocrine data for behavioural studies: the importance of validation (2004)

Buchanan, K. L., Goldsmith, A. R.

Abstract

Faecal, hair of feather samples can indicate only average hormone levels over a considerable, and possibly unkown, period. .. Steroids in faecal and urine samples are highly prone to degradion, probably because of the high levels of bacteria present. .. In conclusion, noninvasive methods of hormone estimation are potentially useful in a range of situations, using hair, feather and faecal samples. But the importance of establishing the validity of each assay technique for each new species and substrate cannot be underestimated.