A second explanation is that the putative Vtg doublet band did not represent our target protein.
Results from our MALDI sequencing of the putative Vtg doublet band however, found significant homology with three Vtg isoforms.
It is not uncommon to find Vtg isoforms of similar molecular weight within vertebrates and not surprisingly , our top MASCOT ion scores were homologous to isoforms representing two chelonian species.
A third and more plausible explanation for the lack of Vtg detection among these females is that they simply could be non-vitellogenic in that year.
Previous research suggests that the energetic demands of vitellogenesis are great.