Marine Biology Commons^™

What Causes The Decrease In Haematocrit During Egg Production?, T. D. Williams, W. O. Challenger, J. K. Christians, M. Evanson, O. Love, F. Vezina

Great Lakes Institute for Environmental Research Publications

1. Anaemia has been reported in wild animals, typically associated with traumatic events or ill health. However, female birds routinely become 'anaemic' during egg-laying; we sought to determine the causes of this reduction in haematocrit. 2. Haematocrit in female European Starlings (Sturnus vulgaris Linnaeus) decreased between pre-breeding and egg-laying in 3 out of 4 years (the decrease was marginally non-significant in the fourth year). This was independent of changes in ambient temperature altering the metabolic requirements for thermoregulation. 3. There was a positive relationship between haematocrit and plasma levels of the yolk precursor vitellogenin among egg-laying birds, supporting the hypothesis …