Daily variations of blood chemistry values in the chinstrap penguin (Pygoscelis antarctica) during the Antarctic summer

• Published in: Comparative Biochemistry and Physiology Part A: Physiology
• Main Authors: Ferrer, Miguel, Amat, Juan A., Viñuela, Javier
• Format: Article in Journal/Newspaper
• Language: English
• Published: 1994
• Subjects: Antarctic; The Antarctic; Antarc*; Antarctica; Chinstrap penguin; Pygoscelis antarctica
• Online Access: http://hdl.handle.net/10261/61847; https://doi.org/10.1016/0300-9629(94)90277-1

We investigated the daily variations of blood chemistry during the 1990- 91 Antarctic summer solstice in six adult chinstrap penguins (Pygoscelis antarctica) in the absence of eat-fast cycles. Four of the seven blood parameters (glucose, urea, triglyceride and cholesterol) showed statistically significant variations between samples at periods of different light intensity. Blood chemistry changes in chinstrap penguins correspond with those expected in a diurnal bird under defined light-dark cycle. In the absence of eat-fast cycle, the daily cycle of light intensity, although greatly attenuated, is the most likely timekeeper (Zeitgeber) for circadian rhythms in blood parameters of chinstrap penguins. Peer Reviewed