The researchers analyzed the feathers in two ways. They divided one batch into subgroups that differentiated three stages of growthbefore, during and after implantation.
In the second part of the study, the scientists wanted to determine if feathers from the same bird would have similar corticosterone levels. To do this, they selected two feathers from the same bird.
An analysis of the feathers yielded several findings. The nine starlings implanted with corticosterone had significantly higher levels of the hormone in their feathers during the study period than the other birds. Also, the scientists found no difference in corticosterone levels between feathers taken from the same bird, indicating a consistency in feathers grown at the same time.
Romero and Lattin are collaborating with other researchers to see if this technique can be applied to preserved bird specimens at the Smithsonian Institute in Washington, D.C. Feathers may be a way to determine whether birds that lived in the wild decades ago lived in stressful environments.
"This opens up the possibility to use museum specimens to look at how changes in the environment may have affected the birds," says Romero.
Elevated Corticosterone is Related to Deformities in Feathers
In previous experiments, the scientists found that feathers from birds implanted with corticosterone in had lighter, weaker feathers. Lattin says that the results suggest that elevated corticosterone levels could impact birds' health.
|Contact: Alex Reid|