Lh. Graham et al., MEASUREMENTS OF FECAL ESTRADIOL AND PROGESTERONE IN NONPREGNANT AND PREGNANT DOMESTIC AND EXOTIC CATS, Journal of Reproduction and Fertility, 1993, pp. 119-120
Faecal samples collected for variable periods from 12 animals and five
species of cats were assayed for progesterone and oestradiol content
by application of standard radioimmunoassays to aliquots (50 mul) of m
ethanol extracts (4 ml) of a mixture of 0.5 g sample, 0.5 ml water and
1 g aluminium oxide, following partitioning of the total extract with
petroleum ether (3 ml), further dilution of assay aliquots and drying
. Recoveries averaged 100 and 72% for oestradiol and progesterone, res
pectively. Results included increases in progesterone during luteal ph
ases or pregnancies to 7688 ng g-1 (tiger, Panthera tigris), 2594 ng g
-1 (lion, P. leo), 3000 ng g-1 (cheetah, Acinonyx jubatus) and 4915 ng
g-1 (caracal, Felis caracal). Faecal oestradiol peaks near oestrus in
cluded 246 ng g-1 (tiger), 175 ng g-1 (lion) 190 ng g-1 (cheetah), 23
ng g-1 (caracal) and 190 ng g-1 (domestic cat, F. catus).