Dogs rescued from shelters often come without medical records or detailed medical histories, and while it is fairly straightforward for rescue groups to get dogs vaccinated and tested for heartworms, it is much harder for breed club groups to determine whether a female has been spayed. A non-invasive, low cost test to evaluate the presence or absence of ovaries could significantly reduce the need for costly, invasive procedures that become a barrier to breed club rescue efforts. Data suggest concentrations of Insulin-like growth factor 1 (IGF-1), a component of the biochemical pathway controlling secretion and actions of insulin, is implicated in multiple aspects of growth and development including development and function of the ovaries. Dr. Root hypothesizes that IGF-1 in blood may be significantly lower in spayed than in unspayed female dogs, and that measurement of IGF-1 could be used to differentiate spayed from unspayed dogs. Through evaluation of IGF-1 concentrations in serum of 40 spayed and 40 intact dogs Dr. Root will determine whether IGF-1 can be developed into a diagnostic test for ovariectomy.