Projects per year
Food hoarding behavior is the storage of food when availability is high for later consumption when resources are scarce. Evidence from mammals indicates a positive influence of ghrelin on its expression and a negative effect of leptin. But little is known about mechanisms underlying hoarding in birds. We are testing the hypothesis that avian hoarding behavior evolved as a modification of the neuroendocrine systems that regulate energy balance in non-hoarding species. In the coal tit (Periparus ater), systemic injection of mouse leptin or chicken ghrelin significantly decreased hoarding activity and mass gain (a proxy of food intake) over a 2-hour post-injection period. This is consistent with the inhibitory effect of both hormones on food intake in non-hoarding avian species and suggests an extension of their regulatory effects to hoarding. To investigate the interaction of central and peripheral nutritional signaling mechanisms, we have used in situ hybridization to localize agouti-related protein, neuropeptide Y, cocaine- and amphetamine-regulated transcript and pro-opiomelanocortin gene expression in the arcuate nucleus of the hypothalamus of the coal tit and a related, non-hoarding, species the great tit (Parus major). We are currently quantifying the effect of acute food deprivation on arcuate nucleus gene expression between these species. In addition, an experiment is underway to quantify and compare the effect of acute food deprivation on hypothalamic gene expression, and that of gut peptides, in the coal tit and another, more similarly-sized, non-hoarding species, the blue tit (Cyanistes caeruleus). This will help to elucidate where differences in nutritional signaling mechanisms between hoarding and non-hoarding species may lie.
|Publication status||Unpublished - May 2019|
|Event||North American Society for Comparative Endocrinology - The University of Florida, Florida, United States|
Duration: 24 May 2019 → 28 May 2019
|Conference||North American Society for Comparative Endocrinology|
|Period||24/05/19 → 28/05/19|