INFORMATION-CONTENT OF SEXUAL SWELLINGS AND FECAL STEROIDS IN SOOTY MANGABEYS (CERCOCEBUS-TORQUATUS-ATYS)

The accuracy and precision of sexual swellings and fecal steroids as m easures of ovarian function and the periovulatory period were compared in 4 sexually mature, individually housed, sooty mangabey females. Fe cal samples were collected daily over a 10-week period during the norm al breeding season. Serum was collected 3 x/week, daily during peak sw elling, and sex skin was rated 5 x/week on a 0-5 relative scale. Both fecal estradiol (fE(2)) and progesterone (fP(4)) were significantly co rrelated with serum values in composite E(2)-aligned profiles and with in the cycles of individual females with average correlations of r(s) = 0.6. Follicular phase means for fE(2) and luteal phase means for fP( 4) were significantly correlated with the serum means across cycles, s uggesting that fecal concentrations could be used to accurately evalua te cycle phases within and across females. In contrast, the timing of peak swelling relative to the periovulatory period varied considerably across the cycles of individual females. Although maximum tumescence appears to bracket the periovulatory period, individual differences in the duration of peak swelling and the timing of its onset and end ten d to obscure the exact time of ovulation in relation to maximal tumesc ence. These data illustrate the utility of fecal steroid analysis as a tool for further evaluation of the signal value of sexual skin and it s role in mating interactions. (C) 1996 Wiley-Liss, Inc.