Poster Presentation The International Congress of Neuroendocrinology 2014

Perception of food affects Corticosterone and behavior but not reproductive hormones in the zebra finch (#217)

Darcy K Ernst 1 , Vanessa A Lane 1 , Cydni Baker 1 , Rebecca Tsai 1 , George E Bentley 1
  1. University of California, Berkeley, Berkeley, CA, United States

Increase in food availability stimulates reproductive activity in zebra finches1 . It is not known if it is increased energy intake or the visual stimulus of food, or both that affects reproductive status. We hypothesize that physical interaction with food as well as visualization of food affects reproduction in zebra finches. To test this, singly-housed birds were videotaped for 1 hour and then randomly assigned to one of four groups: control (ad libitum food), 7 hours of complete food restriction, 7 hours of exposure to a food dish with seed hulls only (no nutritive value), or 7 hours of a food dish covered in clear plastic so birds were able to see food but not touch it (n=10 per group). At the end of treatment birds were videotaped for an additional hour followed by collection of brains, gonads, and blood. ELISA determined no difference between groups in circulating testosterone. Corticosterone was significantly higher in the food restricted group and the group receiving seed hulls than in controls (p<05). Analysis of behavior showed that birds exposed to seed hulls spent significantly more time at their food dish (p<.02) than did control birds or birds with plastic-covered food dishes, while food restricted birds spent an intermediate amount of time at their food dish. The total activity of these birds did not differ by treatment. Perception of food may also affect expression of genes key for reproduction in the hypothalamus, pituitary, and gonads, and these data will be discussed. Overall, our data suggest that a visual food stimulus (food dish covered in plastic) affects zebra finches differently from a food stimulus that they can interact with but receive no nutritional value (hulls only). These data highlight the importance of physical interaction with food when considering how food availability stimulates reproductive activity.

  1. N. Perfito, J.M.Y.Kwong, G.E. Bentley et al. Cue hierarchies and testicular development: Is food a more potent stimulus than day length in an opportunistic breeder (Taeniopygia g. guttata)? Hormones and Behavior, 2008, 53:567-572