Concentrations of faecal immunoreactive progestagen metabolites during the oestrous cycle and pregnancy in the black rhinoceros (Diceros bicornis michaeli)

Abstract

The analysis of reproductive hormones in faecal samples is a possibility for non-invasive monitoring of reproductive status in free-ranging or intractable species. In the present study, faecal samples from three black rhinoceroses (Diceros bicornis michaeli) were collected at about weekly intervals during oestrous cycles and pregnancy. Daily samples were taken during the week after parturition. Total immunoreactive progestagens in faecal extracts were analysed with three different enzymeimmunoassays (EIA) that had considerable specificity for progestagens containing either a 20\g=a\-hydroxyl or a 20-keto group. With each EIA it was possible to distinguish between the follicular and luteal phases of the oestrous cycle. Mating corresponded with low concentrations of faecal progestagens. Samples from five and six consecutive cycles were available from two rhinoceroses and cycle lengths of 24 and 26.5 days were calculated. All three animals became pregnant and the duration of gestation ranged from 440 to 470 days. After fertilization, the concentration of progestagens increased continuously, as in the luteal phase, reaching values 5\p=n-\10times higher between days 60 and 250. During the two weeks before parturition faecal progestagens declined and within 3\p=n-\4 days post partum had reached follicular phase values. It was concluded that several immunoreactive progestagens are present in the faeces of black rhinoceroses and that their measurement with EIA enables non-invasive monitoring of the oestrous cycle and pregnancy.

Faecal Progestagen Profiles in Wild Southern White Rhinoceros (Ceratotherium simum simum)

“…In a previous study describing 5~-reduced pregnane profiles in captive white rhinoceroses this decline prior to parturition was not seen (Patton et al 1999). However, another study found a decline in FPM during the last two weeks of pregnancy in the captive black rhinoceros (Schwarzenberger et al 1993), although this could also be related to the specificity of the antibody used. More detailed endocrine data from white rhinoceroses around parturition are needed to reach a consensus conclusion as to whether a decline of FPM concentrations is, or is not, present in the wild white rhinoceros prior to and/or after parturition.…”

“…Literature reports the existence of two different oestrous cycle lengths in captive white rhinoceros, one with a luteal phase length of 30-35 days and the other of 65-70 days. Only the shorter cycle is believed to be fertile (Hindle et al 1992;Schwarzenberger et al 1993;Radcliffe et al 1997;Patton et al 1999;Brown et al 2001). Also, periods of acyclicity have been found in captivity with a high incidence in both young and aged females (Brown et al 2001;Hermes et al 2006).…”

Foreword: A perspective on the role of emerging technologies for the propagation of companion animals, non-domestic and endangered species

“…The ability to determine timing of oestrus, pregnancy status, sex, seasonality and overall reproductive status provides a powerful tool for breeders and wildlife managers. Development of non-invasive techniques for hormone monitoring (Hindle et al 1992;Schwarzenberger et al 1993) has facilitated sample collection in species where the acquisition of blood samples is difficult or counterproductive (e.g. stress-induced alterations in hormone levels).…”

Excretion rate of progesterone in milk and faeces in lactating dairy cows with two levels of milk yield

“…Briefly, the group-specific antibodies used in the EIAs were raised in rabbits. The assays included 20-oxo-pregnanes (antibody: 5α-pregnane-3β-ol-20-one 3HS:BSA; [35]), 20α-OH-pregnanes (5β-pregnane-3α,20α-diol 3HS:BSA; trivial name pregnanediol; [34]), and 20β-OHpregnanes (antibody: 4-pregnene-20β-ol-3-one 3CMO:BSA; [33]). Significant crossreactivities in these assays were those with 5-reduced P4 metabolites.…”