Behavioral and Physiological Significance of Minimum Resting Metabolic Rate in King Penguins

Because fasting king penguins (Aptenodytes patagonicus) need to conserve energy, it is possible that they exhibit particularly low metabolic rates during periods of rest. We investigated the behavioral and physiological aspects of periods of minimum metabolic rate in king penguins under different circumstances. Heart rate (f(H)) measurements were recorded to estimate rate of oxygen consumption […]

Aggressive behaviour traits predict physiological stress responses in Nile tilapia (Oreochromis niloticus)

This study tested whether aggressive behaviour can predict individual variation in stress responses of Nile tilapia Oreochromis niloticus.We used a mirror test to measure tendency to aggressive behaviour, and calculated the attack frequency and time until the first attack (latency) for each fish. One day later, we measured plasma cortisol and glucose, and two days […]

Diurnal changes of behavior and respiration of Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) in captivity

Abstract 10.1002/zoo.20070.abs A preliminary study was carried out to investigate diurnal changes of behavior of three, one adult male, one adult female, and one juvenile female, Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) in captivity. The respiration and behavior of the porpoises were recorded for 222 hr across 42 days. Behavioral data were recorded for eight […]

Behavioural and physiological assessment of positive and negative emotion in sheep

The assessment of emotional states in animals, particularly positive ones, remains a scientific challenge. We investigated differences in behavioural and physiological measures recorded in sheep, Ovis orientalis aries, during situations likely to coincide with negative, intermediate and positive emotional valence. Reactions of 15 sheep were observed during separation from group members (negative valence), standing in […]

Physiological expression of emotional reactions in sheep

With the aim of judging emotional valence from an animal’s perspective, multiple physiological variables were recorded in sheep when they were exposed to situations likely to induce negative and positive emotional states. Fourteen sheep were conditioned for several weeks to anticipate the delivery of standard feed. In three experimental trials carried out thereafter, the animals’ […]

Thermoregulation, gas exchange, and ventilation in Adelie penguins (Pygoscelis adeliae)

Adelie penguins (Pygoscelis adeliae) experience a wide range of ambient temperatures (Ta) in their natural habitat. We examined body temperature (Tb), oxygen consumption (VO2), carbon dioxide production (VCO2), evaporative water loss (mH2O), and ventilation at Ta from -20 to 30 degrees C. Body temperature did not change significantly between -20 and 20 degrees C (mean […]