Measurement of immunoreactive progestins excreted in faeces as a potential indicator of pregnancy

Abstract

We measured the concentration of immunoreactive progestins extracted from 41 faecal samples of female wood bison (Bison bison athabascae) as a potential indicator of pregnancy. The concentration of faecal progestins fell into two distinct groups, with an approximate 4-fold difference in mean progestin level (1391.9ng g-1 and 58269ng g-1). We suggest that measuring progestin concentration in the faeces of free-ranging animals is a non-invasive method that could be used to assess pregnancy rate.