FECAL PROGESTAGEN CONCENTRATION AS AN INDICATOR OF THE ESTROUS-CYCLE AND PREGNANCY IN MOOSE

We established a noninvasive technique for monitoring the estrous cycl e and pregnancy in moose (Alces alces). We collected fecal samples dai ly from nonpregnant yearling females (n = 3) for the duration of 3-4 e strous cycles, and weekly throughout gestation from 3 pregnant adult c ows. We analyzed samples by radioimmunoassay (RIA) to quantify the con centration of progestagen metabolites. Peak luteal phase concentration s of progestagens were 4.5 +/- 0.9 (SD) mu g/g compared with 0.5 +/- 0 .1 mu g/g during the follicular phase. Observed (n = 7) and suspected (n = 2) matings all occurred within +/-2 days of the nadir in progesta gen excretion. Fecal progestagens were above peak luteal phase concent rations by the eighth week of gestation (>7 mu g/g of feces, P < 0.001 ), permitting accurate pregnancy detection by this time. Relative conc entrations of fecal progestagens during the follicular phase, luteal p hase, and pregnancy were 1:10:35, respectively. Monitoring fecal proge stagen is a useful noninvasive technique for tracking ovarian activity and pregnancy in moose.