Lh. Graham et al., NON-INVASIVE MONITORING OF OVARIAN-FUNCTION IN SEVERAL FELID SPECIES BY MEASUREMENT OF FECAL ESTRADIOL-17-BETA AND PROGESTINS, Zoo biology, 14(3), 1995, pp. 223-237
An extraction and assay procedure to measure fecal estradiol-17 beta a
nd progestin concentrations in several cat species was developed and v
alidated for use for noninvasive monitoring of ovarian function. Fecal
samples were collected over a range of 3-20 months from female tigers
(three), lions (three), snow leopards (three), cheetahs (two), caraca
ls (two), and domestic cats (five). Samples were extracted with 90% me
thanol, lipids removed with petroleum ether, and the estradiol and pro
gestins in the methanol measured by radioimmunoassay (RIA). High Perfo
rmance Liquid Chromatography (HPLC) fractionation and subsequent RIA o
f the fractions indicated that the estradiol-17 beta antiserum cross-r
eacted primarily with estradiol-17 beta in the feces of lions and tige
rs and was assumed to be specific for estradiol-17 beta in the feces o
f other species as well. However, there were several immunoreactive co
mpounds, presumably progesterone metabolites, excreted in the feces wh
ich varied both quantitatively and qualitatively among species. The be
havior of tigers, lions, cheetahs, and caracals was visually monitored
during the collection period and frequency of sexual behaviors was po
sitively correlated with increases in fecal estradiol in all species o
bserved. The mean fecal estradiol-17 beta peaks were as follows: tiger
s, 128.0 +/- 13.1; lions, 186.0 +/- 14.8; snow leopards, 136.7 +/- 15.
9; cheetahs, 140.9 +/- 9.0; caracals, 24.5 +/- 4.0; and domestic cats
158.9 +/- 19.3 ng/gm. Fecal progestin concentrations rose significantl
y (P < 0.001) only after breeding or during pregnancy and were as foll
ows: tigers, 5.6 +/- 0.6; lions, 1.9 +/- 0.1; cheetahs, 8.4 +/- 1.1; a
nd caracals, 2.4 +/- 0.4 mu g/gm. Fecal progestins were elevated for o
ne-half to two-thirds of the gestation length during presumed pseudopr
egnancy but remained elevated throughout successful pregnancies. These
results suggest that ovarian function can be monitored noninvasively
in the family Felidae by the measurement of fecal estradiol-17 beta an
d progestin concentrations (C) 1995 Wiley-Liss, Inc.