Development of a direct microplate enzyme immunoassay for the determination of pregnanediol-3 alpha-glucuronide in urine

A sensitive direct enzyme immunoassay for urine pregnanediol-3 alpha-glucuronide was developed. The assay system involves the use of an antiserum against pregnanediol-3 alpha-glucuronide and an enzyme-labelled antigen chemically prepared by linking beta-D-galactosidase to 20 alpha-hydroxy-5 beta-pregnane 3(O-carboxymethyl)oxime. Free from antibody-bound antigen was separated by a solid-phase double antibody method, using a microplate coupled with goat anti-rabbit gamma-globulin. This solid-phase enzyme immunoassay for urine pregnanediol-3 alpha-glucuronide was validated in terms of specificity, accuracy and sensitivity. When urine samples were assayed for pregnanediol-3 alpha-glucuronide, the results obtained by the solid phase enzyme immunoassay and conventional radioimmunoassay methods agreed well (n = 30, r = 0.922). This assay system has an advantage over radioimmunoassay, because it does not require the use of radioisotopes. The procedure of this method is very simple, since it does not require purification steps of the biological samples.     

Reproductive physiology and development of artificial insemination technology in killer whales (Orcinus orca)

Research was conducted to define the basic reproductive physiology of killer whales (Orcinus orca) and to use this knowledge to facilitate the development of artificial insemination procedures. The specific objectives were 1) to determine the excretory dynamics of urinary LH and ovarian steroid metabolites during the estrous cycle; 2) to evaluate the effect of an exogenously administered, synthetic progesterone analog on reproductive hormone excretion; 3) to validate the use of transabdominal ultrasound for ovarian evaluation and timing of ovulation; 4) to examine the quality of semen after liquid storage and cryopreservation; and 5) to develop an intrauterine insemination technique. Based on urinary endocrine monitoring of 41 follicular phases and 26 complete cycles from five females, estrous cycles were 41 days long and comprised a 17-day follicular phase and a 21-day luteal phase. A consistent temporal relationship was observed between peak estrogen conjugates and the LH surge, the latter of which occurred approximately 0.5 days later. Two animals placed on oral altrenogest (three separate occasions for 30, 17, and 31 days, respectively) excreted peak urinary estrogen concentrations 25 days after withdrawal that were followed by sustained elevations in urinary pregnanediol-3alpha-glucuronide excretion. Mean preovulatory follicle diameter was 3.9 cm (n = 6), and ovulation occurred 38 h (n = 5) after the peak of the LH surge. Based on visual estimates of motility, liquid-stored semen maintained 92% of its raw ejaculate sperm motility index (total progressive motility x kinetic rating [0-5 scale, where 0 = no movement and 5 = rapid progressive movement]) when held at 4 degrees C for 3 days postcollection. Semen cryopreserved using a medium freezing rate demonstrated good postthaw total motility (50%), progressive motility (94%), and kinetic rating (3.5). Insemination during eight estrous cycles resulted in three pregnancies (38%), two from liquid-stored and one from cryopreserved semen. Two calves were delivered after gestation lengths of 552 and 554 days, respectively. These data demonstrate the potential of noninvasive endocrine monitoring combined with serial ultrasonography to improve our understanding of the reproductive biology of cetaceans. This fundamental knowledge was essential for ensuring the first successful conceptions, resulting in live offspring, using artificial insemination in any cetacean species.     

Reproductive status of adult daughters in family groups of common marmosets (Callithrix jacchus jacchus)

Urine samples were collected from 6 pubertal female common marmosets at approximately 3-day intervals over a period of 3-7 months. All 6 females were the eldest daughters in their family groups. 3 of these females were subsequently removed from their families and sampled in isolation for another 2-3 months. Levels of urinary pregnanediol-3 alpha-glucuronide were measured by radioimmunoassay in order to establish whether these females showed ovarian cyclicity. No cyclical fluctuations in the levels of pregnanediol were observed in the females housed with their families even though the females were of a reproductively mature age. Cyclicity was quickly established (within 18-22 days) when the females were removed from the family. These results are discussed in the light of similar recent investigations on callitrichid reproduction and the behavioural implications are considered.     

Reproductive anatomy, manipulation of ovarian activity and non-surgical embryo recovery in suni (Neotragus moschatus zuluensis)

Marked disparity in the uterine horn dimensions and relative degrees of caruncle development in suni suggested that exclusive or predominant dextral implantation occurs in association with bilateral ovulatory activity. Daily urinary measurements of pregnanediol-3 alpha-glucuronide revealed an oestrous cycle of approximately 21 days in length. Ovarian activity was controlled for synchronization of oestrus by using progestagen-impregnated intravaginal sponges and multiple ovulations were induced by using exogenous gonadotrophin therapy. An effective transcervical uterine catheterization technique was developed for the non-surgical collection of embryos. The efficiency of embryo recovery performed 5 days after sponge removal was 50.0%.     

Specificity studies of monoclonal and rabbit antibodies raised against steroid glucuronides

Monoclonal and rabbit antibodies raised against estrone-3-glucuronide and pregnanediol-3 alpha-glucuronide have been studied with respect to their ability to bind free estrone and its conjugates or free pregnanediol and its conjugates, respectively. High titre and high specificity were observed with monoclonal antibodies produced against pregnanediol-3 alpha-glucuronide, whereas the monoclonal antibodies produced against estrone-3-glucuronide were not so specific when compared with the corresponding rabbit antibodies. Both monoclonal and rabbit antibodies had affinity constants in the range of 10(9)--10(10) liter/mole.     

Oestrous cycle of the North American bison (Bison bison) characterized by urinary pregnanediol-3-glucuronide.

An enzyme immunoassay for urinary pregnanediol-3 alpha-glucuronide (PdG) was evaluated for the indirect measurement of progesterone metabolites during the oestrous cycle and early pregnancy of uncaptured North American bison. Comparisons between plasma progesterone and urinary PdG, dose-response parallelism between the standard curve and diluted urine samples and high-performance liquid cochromatography revealed that PdG was a primary immunoreactive urinary metabolite of progesterone in bison. Urine samples were collected directly from the soil from 29 bison cows during the August rutting season and analysed for PdG. Eight bison cows demonstrated complete oestrous cycles ranging from 19 to 26 days (mean cycle length = 23.12 +/- 0.76 days) and behavioural oestrus among four of these cows correlated with PdG nadirs. Mean PdG nadirs were 63.62 +/- 21.61 ng/mg urinary creatinine (Cr) and mean peak midluteal values were 546.01 +/- 130.73 ng/mg Cr. Seven of eight became pregnant, indicating that bison exhibit a second seasonal oestrus. Eighteen other bison cows were pregnant prior to the beginning of the study and demonstrated non-cyclic increased PdG concentrations (greater than 200 ng/mg Cr) during the 30-day course of collection. Three cows ovulated and became pregnant during the 30-day collection period and then exhibited increasing urinary PdG concentrations. This report demonstrates that ovarian function in uncaptured bison can be monitored by means of urinary PdG and that both ovulatory cycles and early pregnancy can be detected.     

Cyclic changes in the circulating and urinary levels of ovarian steroids in the adult female owl monkey (Aotus trivirgatus).

Circulating levels of oestrone and progesterone were measured by radioimmunoassays in plasma samles from 5 female owl monkeys on 60 consecutive days. Both steroids exhibited cyclic fluctuations and based on nadir to nadir intervals the ovarian cycle was estimated to be 15.92 +/- 0.26 days. Levels of oestrone and pregnanediol-3 alpha-glucuronide were also measured in daily urine samples. The fluctuations of urinary steroids reflected those observed in plasma. Ketamine sedation had no effect on the length of the cycle. Peak values of plasma progesterone and oestrone were 250.48 +/- 11.37 and 3.59 +/- 0.066 ng/ml respectively. There was no clear hormonal distinction between the follicular and luteal phase of the cycle in these owl monkeys.     

Monitoring ovarian function and pregnancy in Eld's deer (Cervus eldi thamin) by evaluating urinary steroid metabolite excretion

Direct radioimmunoassays (RIA) for urinary oestrone conjugates and pregnanediol-3 alpha-glucuronide (PdG) were used to study ovarian activity patterns and pregnancy in Eld's deer. In 2 does, urinary metabolite patterns were compared to temporal patterns of plasma LH, oestradiol-17 beta and progesterone. Preovulatory LH peaks occurred coincident with behavioural oestrus, and plasma progesterone secretion paralleled PdG excretion. Although plasma oestradiol-17 beta levels fluctuated between 5 and 10 pg/ml throughout the oestrous cycle, no preovulatory oestrogen surge was observed. Based on PdG excretion, non-conception oestrous cycles averaged 21.5 +/- 2.1 days (+/- s.e.m., n = 65); however, 2 of 13 does exhibited prolonged oestrous cycles (30.1 +/- 4.4 days; range 14-62 days, n = 14) characterized by sustained PdG excretion. Excluding these 2 females, the mean oestrous cycle was 18.5 +/- 0.3 days (range 14-23 days, n = 51). Behavioural oestrus (12-24 h duration) was observed in 42 of 65 cycles (64.6%), and always corresponded with intercyclic troughs in PdG excretion (2-5 days duration). Mean gestation duration (n = 10) was 33.5 +/- 0.4 weeks. PdG concentrations increased (P less than 0.05) by Week -32 (3rd week of gestation), plateaued between Weeks -31 and -25, increased (P less than 0.05) markedly by Week -22 and then rose steadily until parturition, declining (P less than 0.05) rapidly thereafter. Mean excretion of oestrone conjugates remained low until Week -30, increased (P less than 0.05) steadily to Week -24 (P less than 0.05) and then returned to baseline by Week -17. Increased (P less than 0.05) oestrone conjugates concentrations were detected again by Week -4 followed by a rapid increase to peak pregnancy levels by Week -1, declining (P less than 0.05) precipitously after parturition. The results confirm that the Eld's deer is seasonally polyoestrous with onset (January-March) and cessation (August-October) of regular, cyclic ovarian activity coinciding with increasing and decreasing daylengths, respectively. Urinary PdG excretion accurately reflects cyclic ovarian activity and markedly elevated concentrations of this metabolite provide an accurate index of pregnancy. The simultaneous monitoring of oestrone conjugates appears useful for estimating the stage of pregnancy and predicting parturition onset.     

Peripartum Sex Steroid Profiles and Endocrine Correlates of Postpartum Maternal Behavior in Captive Gorillas (Gorilla gorilla gorilla)

An association between pregnancy levels of estrogen and progesterone and maternal behavior has been demonstrated in several taxonomic orders of nonprimate and primate mammals, but has not so far been investigated in the gorilla. In this study we investigated whether prepartum titers of urinary estrone conjugates (E1C) or pregnanediol-3alpha-glucuronide (PdG) were related to postpartum maternal behavior in eight multiparous Western lowland gorilla females (Gorilla gorilla gorilla) housed in four zoological gardens. Urine samples were collected from each study animal for 14 days prepartum and 14 days postpartum, and measures of maternal responsiveness were scored during the first 15 days postpartum. Urine samples were assayed with radioimmunoassay for E1C and PdG. Results for the peripartum profiles of urinary E1C, as well as postpartum profiles of PdG, agree with previous findings for the gorilla, while results for late-pregnancy profiles of urinary PdG were inconclusive in confirming a prepartum increase or decrease. Neither prepartum levels of E1C or PdG, nor the E1C/PdG ratio were found to be related to measures of postpartum maternal behavior. This lack of association between late-pregnancy E1C titers per se and postpartum maternal behavior is contrary to findings in nonprimate and other primate species.     

Reproductive biology of female titi monkeys (Callicebus moloch) in captivity

Titi monkeys (Callicebus spp., Cebidae) are monogamous neotropical primates that live in family-like groups typically consisting of an adult monogamous pair and one or two young. Knowledge about the reproductive biology of this genus is scanty. This study investigated the reproductive biology of female dusky titi monkeys (Callicebus moloch). An initial analysis characterized reproductive parameters of 32 females from a captive colony maintained for 23 years at the California Regional Primate Research Center (CRPRC). The colony records provided data on reproductive parameters such as interbirth intervals, seasonality, age at first pregnancy, and reproductive rate in captivity. Changes in urinary levels of estrone conjugates (E1C) and pregnanediol-3alpha-glucuronide (PdG) were used to characterize major reproductive events. Urine samples from eleven females were collected during 17 months. The endocrine data were used to examine changes associated with cycling, conception, and the post-partum period as well as to determine the duration of the ovarian cycle and gestation length. The analysis of colony records indicated that females whose infant survived through weaning gave birth at intervals remarkably close to one year, while those who lost their offspring showed a significantly shorter interval. As long as they lived within the family group, mature female offspring did not breed. The analysis of the endocrine profiles indicated that after giving birth to a viable offspring, females undergo a relatively prolonged period of anovulation (approx. 6.5 months), followed by 1-3 non-conceptive cycles (approx. 1 month), after which they conceive and gestate (4.3 months).     

Menstrual cycle characterization and artificial insemination in the black mangabey (Cercocebus aterrimus)

Concentrations of immunoreactive estrone conjugates, pregnanediol-3-glucuronide, and luteinizing hormone were measured and indexed to creatinine in daily urine samples from three female black mangabeys (Cercocebus aterrimus). Daily observations of menstruation and perineal tumescence were recorded. The mean ± SEM lengths of the menstrual cycle [apparent cycle length of 26.0 ± 0.8 days determined by observation of intermenstrual intervals (n = 26); physiologic cycle length of 31.3 ± 5 days determined by urinary endocrine analysis (n = 4)], follicular phase [16.5 ± 4 days (n = 4)], and luteal phase [14.8 ± 1 day (n = 4)] were determined. The apparent cycle length is probably more accurate. Perineal tumescence began during or shortly after menstruation, increased concomitantly with increasing follicular phase conjugated estrone values, and reached maximal size in the periovulatory period. Ovulation was closely followed by a drop in conjugated estrone levels, an increase in urinary pregnanediol-3-glucuronide, and perineal detumescence. Peak concentrations of conjugated estrone and luteinizing hormone values were coincident. Pregnanediol-3-glucuronide accurately reflected luteal function in the black mangabey. Knowledge of the menstrual cycle parameters and their correlation to perineal tumescence was used to time artificial inseminations. Semen was obtained by rectal electroejaculation. Coagulum and extended semen, or trypsin-digested coagulum, were used for insemination. One insemination of trypsin-digested coagulum at the external os of the cervix resulted in a probable conception, follówed by apparent abortion after 3 weeks.     

Analysis of urinary immunoreactive steroid metabolites and gonadotropins for characterization of the estrous cycle,breeding period,and seasonal estrous activity of captive killer whales (Orcinus orca)

To increase the basic understanding of killer whale (Orcinus orca) reproductive physiology necessary for the development of artificial breeding programs, we utilized radioimmunoassays (RIA) to detect urinary immunoreactive steroid metabolites (pregnanediol-3α-glucuronide [PdG] and estrone-conjugates [EC]) and gonadotropins (luteinizing hormone [LH] and follicle-stimulating hormone [FSH]) in urine samples from six female killer whales. Urine samples were collected from the whales by voluntary presentation behavior over a 2- to 4-year period. All urinary hormone values were corrected for intersample urine concentration variations by indexing with creatinine. Daily urine samples from four whales were collected during two conceptions and 18 complete estrous cycles. LH, FSH, EC, and PdG immunoreactive levels were determined and combined with observed copulatory activity in five cycles, including two conceptive cycles from two whales. Mean luteal phase lengths ranged from 9.7 to 19.2 days. Mean follicular phase lengths ranged from 6.5 to 16.8 days. Mean estrous cycle lengths based on the first detectable PdG levels were 41.6 ± 6.72 S.E.M. days. After PdG nadir, immunoreactive FSH levels showed a bimodal pattern with the first peak being greater in size, and both preceding a follicular phase EC increase. LH levels > the 95% confidence interval of the mean were considered significant. Combined LH immunoreactive values from whales 2 and 6 during two and three estrous cycles, respectively, had significant LH peak concentrations on day minus 2. These significant LH peaks were assumed to represent the preovulatory LH surge. Eight copulations during two conceptive cycles were observed between whales 2 and 6 and a breeding male. Six of these copulations (3 with each female whale) occurred within 72 hours of the beginning or the end of the presumptive preovulatory LH surge. Estrous activity was seen throughout the year for the herd. However, individuals had varying periods of anestrus that could not be linked to environmental, social, or nutritional influences. The whales that were reproductively successful had anestrus intervals that were usually influenced by gestation, postparturient period, or lactation. The information obtained during this research enhances the foundation for future artificial reproductive management techniques. © 1993 Wiley-Liss, Inc.     

Monitoring fecal samples for estrogen excretion across the ovarian cycle in Goeldi's monkey (Callimico goeldii)

In captive Goeldi's monkeys, estrogen concentration was determined in fecal samples collected from 4 cycling/unmated females and 4 postpartum/mated females in order to ascertain the potential of fecal estrogen monitoring for providing basic information about reproductive status in this endangered Amazonian monkey. Subjects were fed an omnivorous diet and first-void feces were collected in the home cage at 1–3-day intervals for 30–50 days from the cycling females, and at 6–14-day intervals around the estimated time of the postpartum ovulation in each of the 4 mated females. Estimates for the duration of ovarian cycles (22–26 days) and the timing of ovulation were based on cyclic profiles of either blood progesterone or urinary pregnanediol-3α-glucuronide. Fecal estrogen values were normalized using these plasma or urinary profiles. HPLC analysis of estrogen from postpartum fecal samples demonstrated the presence of unconjugated estrone and estradiol-17β (“unconjugated estrogen”). Unconjugated estrogen was extracted and its fecal concentration estimated via EIA. The correlation (r) between plasma estrone conjugates and fecal unconjugated estrogen across nonconception ovarian cycles was 0.65 and measurement of the latter generated cyclic profiles. A range of 4–36-ng unconjugated estrogen g^?1 feces was identified for follicular phases of nonconception cycles. Fecal unconjugated estrogen first exceeded the concentration range of the follicular phase 2–5 days after ovulation; the range was 49–402 ng g^?1 feces in samples collected during the remainder of these nonconception luteal phases. Luteal phase concentrations were on average 10-fold higher than follicular phase concentrations. Each of the 4 mated females conceived at its postpartum ovulation; concentrations of fecal unconjugated estrogen excreted by 3 of these females demonstrated a marked postovulatory increase. This study demonstrates that fecal unconjugated estrogen can be applied to monitor ovarian cyclicity in Goeldi's monkey. © 1994 Wiley-Liss, Inc.     

Selected aspects of female white-faced saki (Pithecia pithecia) reproductive biology in captivity

Little is known regarding the reproductive biology of the white-faced saki. Although sakis have been in zoos since the mid-1970s, little attention has been paid to the reproductive biology of this threatened species. This study describes the results of a 3-year study of the reproduction of the white-faced saki in captivity. Using noninvasive methods to determine levels of estrone conjugates (E₁C) and pregnanediol-3-glucuronide (PdG) in daily urine samples, we have characterized the female reproductive cycle of this species. Nonconceptive ovarian cycles were 16.95 ± 1.57 (SD) days, gestational length was 146.1 ± 5.2 (SD) days, and the length of lactationally induced infertility varied among females but averaged 163 ± 40.6 (SD) days. Attempts to accelerate puberty by pairing a young female with an adult male was without effect. Puberty occurred at 32 months of age in one female. This study provides information that enhances our understanding of the reproductive biology of this species. © 1995 Wiley-Liss, Inc.     

Alpaca semen characteristics under free and directed mounts during a mating period

Most studies in alpaca reproductive biology have been focused on female physiology. Only recent research is being conducted in order to increase the knowledge on males. Semen characteristics during breeding periods will contribute to understanding the poor fertility rates in alpaca.

Ten adult male alpacas were distributed randomly into two groups and submitted alternatively to two regimens of semen collection of 12 days duration (day 1, initial day of semen collection). Semen samples were collected using an artificial vagina and a receptive, non-pregnant female. With regimen 1, males were maintained with females except for the days of sexual rest (6 and 7). Semen was collected on days 1, 5, 8 and 12. With regimen 2, males were exposed to females for daily semen collection only, before and after sexual rest. Mating duration, color and volume of ejaculates, spermatozoa concentration and morphology were evaluated.

No statistical differences for the variables were found between regimens that were used for semen collection. With respect to influence of day, however, the total numbers of spermatozoa ejaculated on days 1 and 5 of semen collection were statistically different (p < 0.05). Azoospermic samples increased on days 5 and 12 of semen collection. Partial recovery in spermatozoa concentration and number of spermatozoa ejaculated were observed after sexual rest. Although normal spermatozoa percentage was less on day 1 (p < 0.05) as compared with values found in the following ejaculates (days 5 and 12), the total number of normal spermatozoa was greater.

These results support the conclusion that when male alpaca have a daily ejaculation during five consecutive days, they might copulate without having enough spermatozoa for fertilization towards the end of the mating period.     

Seasonal variations in semen characteristics, semen cryopreservation, estrus synchronization, and successful artificial insemination in the spotted deer (Axis axis)

Ten adult male spotted deer were monitored over a 2-year interval to determine seasonal variations in testicular size, semen characteristics and serum testosterone concentrations, and to determine if there was an association between season and type of antler. Mean (+/-S.E.M.) testicular volume (118.8+/-4.6 cm(3)), serum testosterone concentration (1.2+/-0.1 ng/mL), semen volume (4.1+/-0.6 mL), sperm concentration (338.3+/-24.9 x 10(6) mL(-1)), percentage of morphologically normal sperm (79.1+/-2.8%), and percentage of motile sperm (66.5+/-1.5%) were higher (P<0.05) in hard antler deer (peaked from March to May) than in deer with velvet antlers or in deer in which the antler has been shed. Thus, March-May was considered the physiologic breeding season for these deer; at this time, all stags had hard antlers. Furthermore, a Tris-citrate-based semen extender containing 4% glycerol and 20% egg-yolk was adequate for cryopreservation of semen. Estrus was induced with an implant containing norgestomet, timed transcervical AI was done with fresh semen, and 3 of 10 females were pregnant at 60 days, with fawns born 120 (premature), 240 and 243 days after AI. These results were considered a model for the use of assisted reproductive techniques to conserve other critically endangered deer species of India.     

Long-term data on basic reproductive parameters and evaluation of endocrine,morphological, and behavioral measures for monitoring reproductive status in a group of semifree-ranging Tonkean macaques (Macaca tonkeana)

Cycle and gestation lengths, menstruation patterns, female genital swelling characteristics, and male-female consortship durations are reported in a semifree-ranging group of Tonkean macaques (Macaca tonkeana) studied over a 12 year period. In addition, profiles of urinary estrone conjugates (E1C) and immunoreactive pregnanediol glucuronide (PdG) throughout four complete menstrual cycles in two females and three full-term pregnancies are presented. Based on intermenstrual intervals, a mean cycle length of 37–41 days (n = 55 cycles in 10 females) was found. Gestation length averaged 173 days (n = 27 pregnancies in eight females). Measurement of PdG immunoreactivity in urine revealed a cyclic pattern with a 5–15-fold increase between follicular and luteal phase concentrations, suggesting that PdG is a reliable indicator of ovarian cyclicity and luteal function. In contrast to PdG, E1C excretion showed no clear pattern throughout the cycle; however, highest values of E1C were usually found shortly before the onset of the luteal phase PdG rise at the presumed time of ovulation. Levels of both hormones were elevated during the first half of gestation and showed a marked increase throughout the second half, with maximum E1C concentrations being up to 100-fold higher than nonpregnant levels. Consortships by the male and occurrence of female genital swelling were long lasting (on average 5–10 days and 13 days, respectively) and were restricted to the follicular phase of the cycle. The day of maximal swelling and day of detumescence as well as the end of male consortship were closely associated with the periovulatory period. Swellings and consortships were longer following lactational ammenorhea than for subsequent cycles. The evolutionary significance of the cyclical changes undergone by females upon their relations with males is discussed. © 1996 Wiley-Liss, Inc.     

Urinary steroid evaluations to monitor ovarian function in exotic ungulates: III. Estrone sulfate and pregnanediol-3-glucuronide excretion in the Indian rhinoceros (Rhinoceros unicornis)

A study was undertaken to identify urinary estrogen and progesterone metabolites in the female Indian rhinoceros (Rhinoceros unicornis). Measurements of these metabolites were then used to monitor ovarian function and establish normal levels and patterns of steroid excretion during the estrous cycle and pregnancy. Urine samples were analyzed for estrone sulfate and pregnanediol-3-glucuronide (PDG) by direct radioimmunoassays. Both hormones produced discrete profiles reflecting ovarian activity in nonconceptive cycles. The estrous cycle was observed to be 48 days (range 39–64) with a mean follicular phase of 14.8 days (range 13–19), followed by a mean luteal phase of 19 days (range 17–21). Of the single gestation monitored, PDG levels rose above luteal phase levels by the third month after breeding and remained elevated throughout gestation. The combined estrogen and progesterone metabolite profiles present a complete evaluation of ovarian steriod production in the mature female Indian rhinoceros.     

Female reproductive cycles and the sexual behavior of moor macaques (Macaca maurus) in their natural habitat,South Sulawesi,Indonesia

The female reproductive cycles and sexual behavior of moor macaques (Macaca maurus) were studied in their natural habitat. Female moor macaques showed repeated perineal swelling. The average cycle length was 36.2 days and the mean duration of swelling was 11.9 days. The estimated duration of gestation in two observed cases was 175 and 176 days, respectively. Females did not exhibit post-conception sexual swelling. Males appeared to ejaculate in multi-mounts. Serial mounting by the alpha male was concentrated on swelling females, while second- and third-ranking males sometimes mounted non-swelling females in series.