Non-invasive detection and monitoring of pregnancy and the postpartum period in goeldi's monkey (Callimico goeldii) using urinary pregnanediol-3α-glucuronide

Aged Black-and-Gold Howler Monkey Female (Alouatta caraya): A Sign of Reproductive Senescence?

Reproductive senescence patterns have been scarcely studied in Neotropical primates. The few studies available on the hormonal profiles of aging female monkeys indicate that the decline of ovarian function in nonhuman primates may resemble the hormonal events associated with the perimenopause in women. In this study, we explore a reproductive hormone profile of an aged black-and-gold howler monkey female (Alouatta caraya) from a wild population in northeastern Argentina and compare this profile with that of a cycling female in the same population. As part of a larger study, we recorded sociosexual behaviors in adult and subadult females belonging to two groups, and we collected urine (n = 877) to determine the sex hormone profile of each female. These samples were analyzed using enzyme immunoassays for estrone conjugates and pregnanediol-3-glucuronide (PdG). We found differences in mean values of PdG between the younger (cycling) and the older female. These hormone values were lower in the older female, and she did not show any signs of cyclicity for either reproductive hormone. Our results show that the aging female in this wild population shows signs of ovarian senescence, indicated by low, acyclic levels of progesterone metabolites.

Changes of urinary steroid conjugates and gonadotropin excretion in the menstrual cycle and pregnancy in the Yunnan snub-nosed monkey (Rhinopithecus bieti)

The Yunnan snub-nosed monkey (Rhinopithecus bieti) is one of the most endangered species in the world, and it is endemic to China. According to our knowledge, there was no information on reproduction for this species. The present study was designed to understand the characteristics of reproductive hormone secretion during the menstrual cycle and pregnancy of this species by monitoring urinary estrone conjugate (E1C), pregnanediol-3-glucuronide (PdG), bioactive follicle-stimulating hormone (FSH), and luteinizing hormone (LH). The urine samples were collected each day from four adult females for eight menstrual cycles, and once in 3 days during pregnancy (three full-term pregnancies, one mid-term abortion). The steroid conjugate was tested by radioimmunoassays (RIAs), and bioactive FSH and LH levels were measured in vitro by the sensitive bioassays granulosa cell aromatize bioassay (GAB) and rat interstitial cell testosterone (RICT), respectively. The results showed that: 1) E1C presented a preovulatory peak (183.9 +/- 8.6 ng/mgCr) followed by a definite elevation of PdG; 2) PdG in the luteal phase (754.4 +/- 30.6 ng/mgCr) was three- to fivefold higher than during the corresponding follicular phase (198.3 +/- 11.4 ng/mgCr); 3) the peaks of bio-LH and bio-FSH were on the same day, while the E1C peak was 1 or 2 days before the peaks for these two hormones; 4) bio-FSH levels were higher in the follicular phase than in the luteal phase, and bio-LH levels elevated slightly in the luteal phase; 5) the mean cycle length was 23.6 +/- 3.5 days (n = 3) based upon successive urinary LH peaks; 6) based on the interval from the day of E1C peak to the day of parturition, the gestation was 203.7 +/- 2.5 days (n = 3); and 7) both E1C and PdG increased and remained high after pregnancy, with a sharp decrease in basal levels following parturition or mid-term abortion. The results suggested that the pattern of reproductive hormones for R. bieti is similar to that of other Old World monkeys, but the concentration of the hormones is different from that of other species. This species has a longer progestation period, which may be related to its classification status.

Non-invasive detection and monitoring of estrus, pregnancy and the postpartum period in pygmy loris (Nycticebus pygmaeus) using fecal estrogen metabolites

Estrone-conjugates (E1C) were measured in the feces of six female pygmy lorises (Nycticebus pygmaeus) during estrus (n = 12), pregnancy (n = 4) and the postpartum period (n = 3). Noninvasive feces collection permitted frequent sampling throughout estrus and pregnancy, without disturbance of animals. The estrous period was defined as an increase in fecal E1C levels above an average of 70 ng/g feces with peaks above 100 ng/g feces obtained in consecutive fecal samples collected over a 6- to 11-day period between the end of July and the first third of October. Comparison of the periovulatory profile of E1C and the stage of labial opening of the vagina revealed a high agreement (P < 0.001). In all pregnant females, an E1C rise was found approximately 47 days postestrus, the source of which may be the growing fetal placental unit. Estimated gestation lengths ranged between 187 and 198 days (n = 4).

Hormonal monitoring of age at sexual maturation in female Goeldi's monkeys (Callimico goeldii) in their family groups

The aim of this study was to determine whether or not sexual maturation is attained in the family group in captive-born Goeldi's monkey (Callimico goeldii) and if so, at what age and body weight. To monitor ovarian activity in 14 female Goeldi's monkeys, urinary content of pregnanediol-3alpha-glucuronide (PdG) was determined using radioimmunoassay. Urinary samples were collected between the ages of 6 and 70 weeks. Subjects became sexually mature while still housed in their family groups, at a median age of 57 weeks (48-< 70 weeks). Median body weight at the age of sexual maturity was 473 g (N=10; 420-543 g). This corresponded to 90% of the median non-pregnant body weight of breeding females in our colony (526 g, N=8). Therefore, Goeldi's monkey is similar to Leontopithecus but different from Cebuella, Callithrix, and Saguinus, in terms of daughters ovulating in the family group and at a relatively young age.

Monitoring hormones in urine and feces of captive bonobos (Pan paniscus)

Urinary and fecal hormones were analyzed on average every other day in 17 female bonobos kept at four US zoos (San Diego Zoo and Wild Animal Park, Milwaukee, Columbus, and Cincinnati). Ovarian cycle activity was monitored throughout the 15-month study period using estrogen and progesterone profiles and swelling charts. Behavioral data on sexual activity were also collected on a daily basis. Fecal and urinary samples were analyzed using high pressure liquid chromatography (HPLC), gas chromatography-mass spectrometry (CG-MS), and nanoelectrospray. Preliminary results indicate that in urine, both conjugated progestin and estrogen metabolites were abundant, while in fecal samples, free progestin metabolites from the 5a-pregnane series were found. Although traces of estrogen metabolites were detected in fecal samples, long-term monitoring of ovarian activity in our study yielded no meaningful estrogen profiles. In contrast, fecal progestin profiles, after adjusting for a one-day delay in excretion, closely matched the corresponding urinary progestin profiles. Using the identical antibody and tracer for both, fecal and urinary progestins, fecal samples yielded approximately ten times the relative amount of progestins compared to urinary progestins. Thus, when converted using a regression formula, fecal progestins may complete the picture obtained from urinary progestins, particularly in cases where the urine sample record is unavailable or incomplete. Evidence of the usefulness of urinary cortisol as a measure of stress is presented.

Physiological Responses to parental separation and a strange situation are related to parental care received in juvenile Goeldi's monkeys (Callimico goeldii)

The relationship between parental care received and physiological and behavioral responses to parental separation, isolation, and reunion was investigated in seven juvenile Goeldi's monkey living in their family groups. Physiological responses were measured non-invasively: the hypothalamic-pituitary-adrenal axis via urinary cortisol output and the autonomic nervous system via piloerection on the tail. Parent-infant aggression demonstrated high intergroup variation and predicted: (a) an increase in urinary cortisol output, r(s) = 0.86, p = 0.04, and duration of piloerection, r(s) = 0.71, p = 0.08, at initial separation-isolation; (b) adaptation of piloerection, r(s) = -0.89, p = 0.03, to repeated separation-isolation. Juvenile Goeldi's monkeys that had received high parental aggression were more physiologically responsive to separation; they also sought more contact with their mothers at reunion, rs = 0.93, p = 0.02. We propose that these data are consistent with the hypothesis that high emotional reactivity is related to insecure attachment to aggressive parents in this New world primate.