Field test of a single-injection gonadotrophin-releasing hormone immunocontraceptive vaccine in female white-tailed deer

Thedevelopmentanduseofsafe,effectiveandpracticalwildlifecontraceptiveagentscouldreducereproduction inlocally overabundant deer populationsinsituations where traditionalmanagement toolssuch as regulated huntingcannot be employed. GonaCon Immunocontraceptive Vaccine (the commercial name for a particular gonadotrophin-releasing hormone(GnRH)-basedemulsion)wastestedinadultfemalewhite-taileddeerinafencedherdnearSilverSpring,Maryland, USA. Observations of udder condition were used to identify does that had become pregnant. Necropsy observations, histopathology and serum concentrations of anti-GnRH antibodies, luteinising hormone and progesterone were used to comparehealthandreproductivestatusoftreated(n=28)andcontrol(n=15)deer.AfterreceivingoneinjectionofGonaCon, 88% of treated deer did not become pregnant during the first year and 47% did not become pregnant during the second year aftervaccination.NoadversehealtheffectsrelatedtovaccinationwithGonaConweredetected,exceptforlocalisedinjection- site reactions in five (29%) of 17 examined, vaccinated deer. Treatment with GonaCon can be a safe and effective means of inducingtemporaryinfertilityinwildwhite-taileddeer.Ultimately,themanagementvalueofGonaConwillbedeterminedby natural-resource professionals who use it as one of many tools to manage deer populations.