Summary: Conservation Genetics 2: 385390, 2001.
© 2001 Kluwer Academic Publishers. Printed in the Netherlands.
Eggs yield nuclear DNA from egg-laying female cowbirds, their embryos
B.M. Strausberger & M.V. Ashley
Department of Biological Sciences (MC 066), University of Illinois at Chicago, 845 West Taylor Street, Chicago,
Il 60607, USA (Author for correspondence: E-mail: firstname.lastname@example.org)
Received 14 November 2000; accepted 30 March 2001
Key words: brood parasitism, cowbird, DNA extraction, genetic analysis, noninvasive sampling
Here we report methods for extracting maternal DNA from avian eggshells or offspring DNA from eggshells
and embryos. These methods offer alternative techniques for obtaining DNA from oviparous organisms. Using
DNA extracted from eggshells, we obtain microsatellite genotypes of the brood parasitic brown-headed cowbird
(Molothrus ater) female that laid the eggs and/or her hatched offspring. Using DNA extracted from embryos, we
obtain microsatellite genotypes of offspring. We demonstrate that separate extractions performed on the embryo
and shell from a single egg can provide DNA from the embryo and its mother, respectively. This single-egg
approach for obtaining both maternal and embryonic DNA simplifies paternity analyses because alleles unique to
the embryo can be considered paternal in origin. Finally we report two new microsatellite loci and primer sequences
for brown-headed cowbirds.