Combined serial ultrasonography and fecal progestin analysis for reproductive evaluation of the female white rhinoceros (Ceratotherium simum simum): Preliminary results

Abstract

Ultrasonographic examinations of one multiparous 33‐year‐old female southern white rhinoceros (Ceratotherium simum simum) resulted in documentation of the animal's estrous cycle, elucidation of the timing of ovulation in relation to estrus, and ultrasonographic evidence of endometritis and associated early embryonic death. The preovulatory follicle was observed to change in shape from spherical to pear‐shape (n = 3) and to reach a mean follicular diameter of ˜30 mm (n = 4) in the 48 hr preceding estrus. An ovulation site in the location of the preovulatory follicle was observed to occur within 24 hr postbreeding on one occasion. Both pregnancies monitored in this female in 1995 were lost by day 28 postovulation, with collapse of the embryonic vesicle documented via ultrasound. Ultrasonographic evidence of endometritis was observed in this female and was characterized by small quantities of anechoic intrauterine fluid collections (5–20 mm diameter) in late diestrus (n = 4, mean day observed was 20.5 days postovulation, with a range of 18–24 days). Fecal samples collected at the time of ultrasound were evaluated via radioimmunoassay for progesterone metabolites. A substantial rise in fecal progestins was not identified until 7–9 days postovulation. This study illustrates the value of combining the complementary techniques of ultrasonographic “mapping” of events with fecal hormone assay to enhance the accuracy of reproductive monitoring. Zoo Biol 16:445–456, 1997. © 1997 Wiley‐Liss, Inc.

Luteogenesis during the estrous cycle in Asian elephants (Elephas maximus)

“…As soon as P m reached baseline (follicular phase) values, follicles started developing. This is in contrast to other megavertebrae species such as giraffe (Lueders et al 2009) or rhinoceros (Radcliffe et al 1997) where follicles are constantly forming in all reproductive stages, even under the influence of a functional CL. In elephants, high P m levels appear to completely inhibit antral follicle formation.…”

“…The luteal cells of the acCLs may require the second LH peak to mature and become fully steroidogenically active. In Baringo giraffes (Giraffa camelopardalis rothschildi) and white rhinoceros (Ceratotherium simum simum) a time span of 5-6 and 7-9 days respectively has been reported from ovulation to first rise in progesterone levels (Radcliffe et al 1997, Lueders et al 2009). The short period from ovulation to increased P m concentrations in the Asian elephant supports the hypothesis that the acCL may initially be responsible for secreting this hormone while the ovCL contributes and maintains P m during the remainder of the luteal phase.…”

Non-invasive assessment of oestrous cycles and evaluation of reproductive seasonality in the female wild black rhinoceros (Diceros bicornis minor)

“…Part of this lag may be attributable to the delay coinciding with the entero-hepatic circulation and faecal excretion of steroids, estimated to be 2-3 days in rhinocerotids (Hindle and Hodges, 1990;Heistermann et al, 1998), as well as to the delay of 2-3 days observed between onset of oestrus and ovulation in black rhinoceroses (Radcliffe et al, 2001). In addition, another interval probably occurs between ovulation and the subsequent increase in faecal progestagens, as has been described in white rhinoceroses (Radcliffe et al, 1997;Schwarzenberger et al, 1999).…”

“…This pathology has been identified in three captive white rhinoceros females, and the corresponding luteal phases, identified by faecal pregnane analysis, lasted about twice the average cycle duration (Radcliffe et al, 1997;Patton et al, 1999). These reports, combined with the fact that a history of mating followed by anoestrus without pregnancy in mares is indicative of early embryo loss (Youngquist, 1997), indicate that such pathology may be associated with type IIa cycles.…”

“…In rhinoceros species, faecal progestagen analysis has permitted the monitoring of gestation and diagnosis of pregnancy in both wild and captive black and white rhinoceroses (Schwarzenberger et al, 1993, in press;Berkeley et al, 1997;Radcliffe et al, 1997;Garnier et al, 1998a;Patton et al, 1999), and in captive Indian rhinoceroses (Schwarzenberger et al, 2000). The analysis of faecal progestagen has also allowed the assessment of luteal activity in captivity in white (Patton et al, 1999), Indian (Schwarzenberger et al, 2000) and Sumatran rhinoceroses (Heistermann et al, 1998).…”