Urinary oestradiol and testosterone levels from novel male mice approach values sufficient to disrupt early pregnancy in nearby inseminated females.

摘要: Previous research has established that exposure to novel male mice can disrupt intrauterine implantation of fertilised ova in inseminated females and much this effect is mediated by factors the urine. The present studies were designed examine whether steroid content urine sufficient account for effect. Pregnancy was terminated exogenous 17beta-oestradiol administered intranasally on days 2-4 after insemination doses as low 0.14 microg/day. Enzyme immunoassay indicated mouse reliably contains unconjugated testosterone. A small but significant increase amount urinary oestradiol observed males housed nearby previously opposed those isolation. This influence absent sire when also present. quantity active steroids approaches level disruption females.