We investigated the seasonal and daily variation in plasma glucose levels in response to stress in captive wild starlings. Starlings were captured from the wild during the winter, held on short days (11L:13D, mimicking winter), and then shifted to long days (19L:5D, mimicking summer). Birds were maintained on long days until they began a prebasic molt, the energetically costly replacement of fe...

Stress-induced effects on innate immune activity in wild birds have been difficult to predict. These difficulties may arise from the frequent assumptions that (1) the stress response influences different components of the immune response similarly, (2) stress-induced effects do not change over the course of the stress response and (3) glucocorticoids are the primary regulators of stress-induced...

Haemoparasites are one of the most important groups bird parasites, with emphasis on genera Haemoproteus, Plasmodium, Leucocytozoon and Trypanosoma. Zoos sustain different wild animals valuable tools for education conservation species. The conditions captive differ from animals, as zoos have sufficient availability food throughout year, protection against predators veterinary care animals. This...

Carotenoids cannot be synthesised by vertebrates and must be derived from the diet. A growing amount of research has focussed on the role of carotenoids in immune function, as well as the signalling function of carotenoids in the colour of the integument (skin, bill and legs) and feathers. We used an experimental approach to examine the effects of experimental reduction and supplementation of d...

The purpose of this study was to investigate the presence of the anaerobic intestinal spirochetes Brachyspira aalborgi and Brachyspira pilosicoli in the feces of captive nonhuman primates (n = 35) from 19 species housed at the Zoological Gardens, Perth, Western Australia. Both spirochete species are known to infect human beings. DNA was extracted from freshly collected feces with a commercially...

The adult hippocampus in birds and mammals undergoes neurogenesis and the resulting new neurons appear to integrate structurally and functionally into the existing neural architecture. However, the factors underlying the regulation of new neuron production is still under scrutiny. In recent years, the concept that spatial memory affects adult hippocampal neurogenesis has gained acceptance, alth...

Enrichment is widely used as tool for managing fearfulness, undesirable behaviors, and stress in captive animals, and for studying exploration and personality. Inconsistencies in previous studies of physiological and behavioral responses to enrichment led us to hypothesize that enrichment and its removal are stressful environmental changes to which the hormone corticosterone and fearfulness, ac...

In seasonal environments animals organize their behaviour around annual cycles of resource availability. Wild black-capped chickadees are most likely to hoard food in autumn. At this time of year chickadees are also reported to have a larger hippocampus, a brain area important for spatial memory. This study examined how photoperiodic condition affects these seasonal changes. Captive chickadees ...