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Publisher: Elsevier BV
Date: 11-2011
Publisher: CSIRO Publishing
Date: 2020
DOI: 10.1071/RD20001
Publisher: Elsevier BV
Date: 08-2013
DOI: 10.1016/J.ANIREPROSCI.2013.06.005
Abstract: Determining the reproductive status of long-term captive animals is essential because the onset of sexual maturity and reproductive activity may necessitate changes in husbandry requirements. This study reports on the first multi-year reproductive hormone monitoring program for captive dugongs of both sexes using feces. Fecal s les were collected from one male (Pig) over 9 years (4-13.2y of age n=288 s les, 0.8±0.1 s les per week from July 2007 to February 2012) and one female (Wuru) over 7 years (from neonate to 6.9 y n=171 s les, 0.5±0.1 s les per week from July 2007 to February 2012), and from one solitary female dugong (Gracie) over 10 months (10.5-11.3y of age n=54 s les, 1.1±0.2 s le per week from September 2008 to June 2009). Using enzyme-immunoassay, fecal progesterone (fP) and estradiol-17β (fE) concentrations were assayed in the two captive females, and testosterone (fT) concentration in the captive male, and compared these to concentrations in wild dugongs. Female Wuru exhibited increasing fP concentrations at 5+ y, indicating early onset of ovarian cycling typical of non-pregnant adult females. Female Gracie maintained basal fP concentrations consistent with wild immature dugongs, indicating that she had not reached puberty by 11y. Nutritional plane may account for differences in age at sexual maturity in these female dugongs. At age 3-4y, Wuru had fE concentrations 1.4 times greater than maximum concentrations recorded in all wild females, and these concentrations were coincident with a period of rapid weight gain. For the male Pig, increasing fT concentrations at 9y provided early indications of puberty. Pig's tusks erupted by 11y, and sexual maturity (indicated by spermatic semen) was confirmed by 12.8y. Identification of sexual maturation prompted two trials of a male contraceptive treatment using the GnRH agonist, deslorelin (9.4mg administered in 2010 and 15.6mg in 2011). Testosterone production was not significantly suppressed by these dosages, and treatment did not terminate sperm production at week 10-11 post-implantation, even at the larger dose tested. Routine analysis of fecal hormones was helpful for making reproductive management decisions regarding in idual captives and in guiding the long-term captive management of this cryptic species.
Publisher: Springer Science and Business Media LLC
Date: 08-03-2018
DOI: 10.1038/S41598-018-20934-9
Abstract: Devil Facial Tumour Disease (DFTD), a highly contagious cancer, has decimated Tasmanian devil ( Sarcophilus harrisii ) numbers in the wild. To ensure its long-term survival, a captive breeding program was implemented but has not been as successful as envisaged at its launch in 2005. We therefore investigated the reproductive success of 65 captive devil pair combinations, of which 35 produced offspring (successful pairs) whereas the remaining 30 pairs, despite being observed mating, produced no offspring (unsuccessful pairs). The devils were screened at six MHC Class I-linked microsatellite loci. Our analyses revealed that younger females had a higher probability of being successful than older females. In the successful pairs we also observed a higher difference in total number of heterozygous loci, i.e. when one devil had a high total number of heterozygous loci, its partner had low numbers. Our results therefore suggest that devil reproductive success is subject to disruptive MHC selection, which to our knowledge has never been recorded in any vertebrate. In order to enhance the success of the captive breeding program the results from the present study show the importance of using young (2-year old) females as well as subjecting the devils to MHC genotyping.
Publisher: Wiley
Date: 14-03-2012
DOI: 10.1002/ZOO.20384
Abstract: The Vancouver Island marmot (Marmota vancouverensis VIM) is one of North America's most endangered species with fewer than 150 in iduals remaining in the wild. A captive breeding program was established across four facilities in Canada as an insurance population and source of animals for reintroduction to the wild. The purpose of this study was to gather information about the basic reproductive biology and behavior of this species, which is essential to improve captive breeding programs. Regular fecal s les were obtained from adult female (n = 14) and male (n = 10) marmots, 2 years of age and older, over 1-3 breeding seasons (2-3 months duration posthibernation) for steroid hormone analysis. Enzyme immunoassays were validated for quantifying fecal testosterone metabolite concentrations for males, and fecal estrogen and progesterone metabolite concentrations for females. Results indicated that fecal progesterone metabolite concentrations can be used to monitor ovulation and pregnancy. Behavioral monitoring through infrared video surveillance was conducted in four breeding pairs over a 2-year period (n = 7 behavioral profiles). Breeding behaviors correlated strongly with changes in reproductive endocrine profiles. A high frequency of play behavior or "wrestling" was observed in conjunction with breeding activity before an elevation in progesterone metabolite concentrations. Impending parturition was associated with increased aggression and exclusion of the male from the maternal nestbox as well as an increase in nesting activity. Observational data combined with hormonal analysis suggest that female VIMs are induced ovulators and that multiple breeding attempts may be required for ovulation and conception. Gestation appears to be approximately 34 days from peak breeding activity (32 days from estimated ovulation). Fecal testosterone concentrations suggest that testicular activity is seasonal with the reproductive activity occurring immediately posthibernation. Monitoring breeding behavior is a useful means of indicating estrus, conception and pregnancy, which can also be supported by the hormonal analysis of daily fecal s les of in idual animals.
Publisher: Bioscientifica
Date: 06-2014
DOI: 10.1530/EC-14-0025
Abstract: In the context of reproduction, glucocorticoids (GCs) are generally considered to have negative effects. However, in well-studied model species, GCs fluctuate predictability across the estrous cycles, and short-term increases promote healthy ovarian function. Reproductive challenges have plagued captive elephant populations, which are not currently self-sustaining. Efforts to understand reproductive dysfunction in elephants have focused on the suppressive effects of cortisol, but the potential permissive or stimulatory effects of cortisol are unknown. In this study, we provide a detailed examination of cortisol patterns across the estrous cycle in Asian elephants ( Elephas maximus ). Time series analysis was used to analyze cortisol and progesterone data for a total of 73 cycles from eight females. We also compared cortisol profiles between females that successfully conceived and females that failed to conceive despite repeated mating attempts. Our results revealed that cortisol fluctuates predictably across the estrous cycle, with a peak during the second half of the follicular phase followed by low levels throughout the luteal phase. Furthermore, this pattern was significantly altered in nulliparous females cortisol concentrations did not decline during the luteal phase to the same extent as in parous females. This study highlights the complexity of cortisol signaling and suggests future directions for understanding the role of cortisol in reproductive dysfunction.
Publisher: CSIRO Publishing
Date: 2018
DOI: 10.1071/RD17539
Abstract: The poor captive breeding success of southern hairy-nosed wombats (SHNWs Lasiorhinus latifrons) has been attributed to the difficulty in accurately characterising oestrous behaviour and their relationship to circulating reproductive hormones. Over two wombat breeding seasons, the use of infrared cameras for 24-h remote behavioural monitoring and the analysis of urine s les collected from seven captive females, were investigated to determine the relationship between behaviour and changes in urinary progesterone metabolites (P4M). Urinary P4M was ided into two concentrations: (1) ≤ baseline P4M values and (2) baseline P4M values and evaluated against urine volume (mL) and the duration (s) and frequency of 23 behaviours recorded for 8 days surrounding D0 of the luteal phase (D0: a sustained increase in P4M for three or more consecutive days). When P4M was ≤ baseline, the duration of urination and volume both decreased, whereas the duration and frequency of both pacing and rump bites by the female towards the male increased. These results suggest that there were detectable behavioural changes that can be mapped to the changes in the SHNW oestrous cycle, which may be used as behavioural indicators to identify the reproductive status of females.
Publisher: CSIRO Publishing
Date: 2019
DOI: 10.1071/RD18407
Abstract: Contraception is increasingly used to manage breeding opportunities in conservation-dependent species. This study aimed to determine the efficacy, duration of effect, optimal dose and potential side effects of Suprelorin contraceptive implants in Tasmanian devils, for use in the conservation breeding program. In our pilot study, Suprelorin was found to effectively suppress oestrous cycles in female devils, yet caused a paradoxical increase in testosterone in males. Therefore, we focussed on females in further trials. Females received one (n=5), two (n=5) or no (n=5) Suprelorin implants, with quarterly gonadotrophin-releasing hormone (GnRH) challenges used to test pituitary responsiveness over two breeding seasons. Both Suprelorin doses suppressed pituitary responsiveness for at least one breeding season, with a reduced effect in the second. There was a dose-response effect on duration rather than magnitude of effect, with high-dose devils remaining suppressed for longer than low-dose animals. There were no apparent negative effects on general health, yet captivity and contraception together may cause weight gain. Suprelorin contraceptive implants are now routinely used in the Save the Tasmanian Devil Program insurance metapopulation to meet the aims of maintaining genetic and behavioural integrity by controlling in idual reproductive contributions in group housing situations.
Publisher: CSIRO Publishing
Date: 2012
DOI: 10.1071/RD11134
Abstract: Devil facial tumour disease (DFTD) is the cause of the rapid decline of wild Tasmanian devils. Female devils are seasonal breeders with births peaking during autumn (i.e. March) but the degree of reproductive seasonality in male devils is unknown. The objective of this study was to examine the potential effects of season and DFTD on reproductive function in male devils (n = 55). Testicular (1.90 ± 0.23 g) and epididymal (0.90 ± 0.06 g) weights were maximal during autumn and spring (P 0.05), whereas prostate (3.71 ± 0.74 g) and Cowper’s gland (0.68 ± 0.22 0.52 ± 0.21 g) weights peaked during autumn (P 0.001). The motility of spermatozoa from the cauda epididymides extracted post-mortem was similar (P 0.05) across season and disease state (31.5 ± 13.1% total motility). Testicular and epididymal weights were no different between animals displaying late or early-stage DTFD signs or disease-free animals (P 0.1). The accessory sex glands were larger in late-stage DFTD animals than in animals with early-stage disease signs or which were disease-free (P 0.01) but effects of season on this result can’t be excluded. Serum testosterone concentrations peaked during summer (0.25 ± 0.18 ng mL–1) but values were not different from the preceding and subsequent seasons (P 0.05), nor influenced by disease stage (P 0.1). Seasonal and DFTD-related changes in serum cortisol concentrations were not evident (P 0.1). Male devil reproduction does not appear to be restricted by season nor inhibited by DFTD.
Publisher: Royal Zoological Society of New South Wales
Date: 2010
DOI: 10.7882/AZ.2010.020
Publisher: Wiley
Date: 26-09-2007
Publisher: CSIRO Publishing
Date: 2012
DOI: 10.1071/RD12022
Abstract: Electroejaculation (EEJ) has been used successfully to collect s les suitable for genome resource banking from a variety of endangered wildlife species. Ejaculates can also be used to evaluate the reproductive potential of in iduals and provide information on seminal characteristics to aid in the development of sperm cryopreservation techniques. Electroejaculation techniques used for marsupial and eutherian species were tested on Tasmanian devils (n = 35). Spermic ejaculates were collected in 54% (19/35) of EEJ attempts. Spermic ejaculates were low in volume (3.9 ± 6.5 × 102 µL, range 10–3000 µL) and contained low numbers of spermatozoa (3.3 ± 7.8 × 103 spermatozoa per ejaculate, range 6–33 000). The osmolality and pH of presumptive urine-free ejaculates were 389 ± 130 mOsm kg–1 (range 102–566) and 7.0 ± 0.9 (range 6.0–8.0), respectively. Prostatic bodies were observed in 79% (26/33) of ejaculates. Episodic fluctuations in serum testosterone concentrations were not detected during the EEJ procedure (P 0.05). Increases observed in serum cortisol concentrations during EEJ were less (P 0.05) than those observed after an adrenalcorticotropic hormone challenge and diurnal variation suggested that cortisol concentrations are greater during the day than at night (P 0.05). This information can be used to provide range values for the future examination of basic endocrine responses and the adrenal–pituitary axis of this species. This study also demonstrated that spermatozoa-rich devil electroejaculates are more difficult to obtain and poorer in quality than those of other marsupials.
Publisher: Elsevier BV
Date: 2020
DOI: 10.1016/J.YHBEH.2019.104606
Abstract: For most cetacean species, there is little known about how an in idual's physiology influences its behaviour. Humpback whales (Megaptera novaeangliae) are a good candidate to examine such links as they have a well-described distribution and behaviour, can be consistently s led using remote biopsy systems, and have been the subject of several previous endocrine studies. The objective here was to examine whether a female humpback whale's social state (i.e. escorted by a male or not) is related to her endocrine condition, and whether male dominance ranking is related to testosterone levels. Skin and blubber biopsies were collected from the east and west Australian humpback whale populations in 2010-2016 (n = 252) at multiple times throughout the winter-spring breeding season. Steroid hormones were extracted from blubber and concentrations of progesterone (a marker for pregnancy), testosterone (a marker of male testicular activity) and oestradiol (a potential marker of ovarian activity) measured using enzyme-immunoassays. Principal escorts-the dominant males in mixed sex groups-had significantly higher blubber testosterone levels (mean ± SE 1.43 ± 0.20 ng/g wet weight) than subordinate, secondary escorts (0.69 ± 0.06 ng/g wet weight). Females that were escorted by males typically possessed elevated blubber oestradiol levels (1.96 ± 0.25 ng/g wet weight p = 0.014) few were considered to be pregnant (p = 0.083). 'Unescorted' females displayed characteristically lower blubber oestradiol levels (0.56 ± 0.06 ng/g wet weight). Together, these results are consistent with 'challenge hypothesis' theory and suggest the existence of associated reproductive patterns in humpback whales.
Publisher: Elsevier BV
Date: 08-2016
DOI: 10.1016/J.RVSC.2016.05.002
Abstract: This study reports the first documented clinical case of a spermatic granuloma and varicocele in a marsupial. Initial clinical presentation included gross morphological changes in the left scrotal cord, epididymis and testis. Ultrasonography of the scrotum and spermatic cord, and gross and histopathological examination after hemicastration, confirmed the condition as a spermatic granuloma affecting the left caput epididymis, with a varicocele in the left proximal spermatic cord, which was causing azoospermia and infertility. Semen quality and serum testosterone secretion following a GnRH challenge was assessed prior to, and following surgery. After hemi-castration, an increase in androgen secretion to within normal reference ranges for the koala was observed with a subsequent increase in semen production and sperm quality resulting in the sire of a pouch young, 12months later.
Publisher: CSIRO Publishing
Date: 2018
DOI: 10.1071/RD17497
Abstract: Southern hairy-nosed wombats (SHNWs: Lasiorhinus latifrons) do not breed well in captivity. To better understand their reproduction, daily urine s les were collected from nine captive females and analysed for volume (mL), specific gravity and a qualitative index of the number of epithelial cells, then stored at −20°C until s les could be analysed for progesterone metabolites (P4M). The mean oestrous cycle length was 35.1 ± 2.4 days however, in idual cycle length ranged from 23 to 47 days. The mean luteal phase length was 20.8 ± 1.3 days (range: 12 to 33 days). Urinary P4M was ided into four oestrous cycle stages: (1) early follicular phase, (2) late follicular phase, (3) early luteal phase, (4) late luteal phase, and analysed against urinary characteristics. During the late follicular phase, urine volume decreased (P = 0.002) while urine specific gravity (P = 0.001) and concentration of epithelial cells (P = 0.004) both increased. The level of variability in oestrous cycle length suggests that some captive females may exhibit abnormal cycles however, the changes in the urinary characteristics associated with the different stages of the oestrous cycle appear to offer a possible non-invasive means of monitoring the reproductive status of captive SHNWs.
Publisher: CSIRO Publishing
Date: 2012
DOI: 10.1071/AM11047
Abstract: Faecal hormone metabolite analysis offers a non-invasive alternative to blood s ling that is particularly relevant to wild animal populations. It has been used for reproductive and adrenal hormone monitoring in captive wombats, but no information exists on its accuracy when s le storage is delayed or on whether variation exists within s les. This study aimed to quantify the effect of storage delay and intras le variation on faecal metabolite concentrations of testosterone, progesterone and corticosterone in southern hairy-nosed wombats. For all metabolites, intras le variance was 15% or less of total variance. Delays in storage significantly changed metabolite concentrations, with progesterone showing a progressive decrease over time (0–72 h: t24 = 2.14, P = 0.05), testosterone showing a significant increase after 6-h delay (0–6 h: t21 = 2.83, P = 0.01), and corticosterone showing an initial increase (0–6 h: t48 = 3.60, P = 0.001), followed by a reduction to original concentrations by 72 h (0–72 h: t48 = 0.91, P = 0.38). Although changes caused by storage delays may not obscure large hormonal fluctuations, this study outlines the importance of immediate storage and consistent s ling to allow the most accurate results to be obtained.
Publisher: Elsevier BV
Date: 03-2022
DOI: 10.1016/J.THERIOGENOLOGY.2021.12.011
Abstract: There is growing evidence that Chlamydia pecorum infection of the male koala reproductive tract causes inflammation and pathology of the urogenital tract. Previous studies have revealed that male koalas exhibiting severe clinical signs of urogenital chlamydial disease had an increased incidence of sperm DNA fragmentation and abnormal sperm morphology, suggestive of chronic exposure to C. pecorum infection and/or inflammation in the testis and epididymis, with residual pathology and lesions disrupting spermatogenesis and maturation of spermatozoa. This study specifically aimed to determine whether pathology associated with chlamydial infection in different regions of the male koala reproductive tract had an adverse effect on classical seminal parameters, sperm DNA quality and endocrine function (testosterone secretion) of naturally infected males. Semen from 58 sexually mature male koalas deemed not suitable for rehabilitation or treatment was assessed, in addition to undertaking a GnRH challenge to determine the androgenic capacity of the testis. Following euthanasia, tissue s les from testes, epididymis and prostate were evaluated for histopathology and real time polymerase chain reaction (qPCR). A significant difference in sperm concentration was observed between males with unilateral and bilateral testicular atrophy and C. pecorum infection (P = 0.011) and between males with unilateral atrophy and C. pecorum infection in one testis and bilateral normal testes with no C. pecorum infection (P = 0.008). No significant association was found for any other semen parameters when categorised by histopathology and C. pecorum tissue presence within the testes, epididymis and prostate. Plasma testosterone concentrations did not significantly differ between testicular histopathology diagnosis and/or C. pecorum infection status. This study suggests Chlamydia infection and inflammation may not be the predominant reason of disruption to spermatogenesis in the wild koala but rather testicular degeneration and atrophy, irrespective of Chlamydia infection, appears to be the primary reason of decreased sperm concentration.
Publisher: Elsevier BV
Date: 04-2019
DOI: 10.1016/J.YGCEN.2018.12.015
Abstract: Blubber and respiratory vapour ('blow') are now commonly used for endocrine studies on cetaceans, primarily because they can be obtained using minimally invasive methods. For many species, these s les have yet to be validated for these purposes. The objective of this study was to examine the performance of blow and blubber hormone monitoring, relative to serum hormone monitoring, for evaluating the reproductive and adrenal condition of captive bottlenose dolphins (Tursiops spp.). Eighteen bottlenose dolphins were s led five times for serum and blow and twice for blubber throughout a one-year period. Concentrations of progesterone, testosterone, oestradiol and cortisol were measured in each s le type. Hormone levels were examined in relation to dolphin age, sex, reproductive status, season, time of s le collection (morning/afternoon) and collection type (in- or out-of-water s ling). Patterns in hormone levels were similar for serum and blubber. For instance, in both s le types, progesterone levels were significantly higher in pregnant (serum: 34.10 ± 8.64 ng/mL blubber: 13.01 ± 0.72 ng/g) than in non-pregnant females (serum: 0.32 ± 0.09 ng/mL blubber: 1.17 ± 0.10 ng/g). This pattern was not detected in blow, primarily because seawater contamination, nylon s ling materials and variable s le volumes influenced measured concentrations. In addition, the respiratory water content of a blow s le is known to affect measured hormone levels. Two methods were trialled to control for variability in s le volumes and dilution: (1) normalising blow hormone concentrations relative to urea nitrogen levels (a potential endogenous standard), and (2) measuring the relative proportions (i.e. ratios) of blow hormones. These correction measures had little influence on blow hormone results. Further refinement of blow hormone monitoring methods is required before they can be used for reproductive or adrenal assessments of bottlenose dolphins. Blubber, on the other hand, should be a suitable proxy for serum when attempting to classify pregnancy status and male maturity in these species.
Publisher: Elsevier BV
Date: 09-2017
DOI: 10.1016/J.YGCEN.2017.06.001
Abstract: This study reports the validation and use of enzyme immunoassays (EIA) to measure changes in plasma and urinary luteinizing hormone, testosterone metabolites (UTM) and cortisol metabolites (UCM) in captive southern hairy-nosed wombats (Lasiorhinus latifrons). GnRH agonist and ACTH agonist challenges were conducted to validate urinary testosterone (male wombat only) and cortisol (male and female wombats) EIAs. Following intra-muscular injection of 8-12μg buserelin (n=4 males), there was a significant increase in both plasma (P<0.001) and urinary testosterone concentrations (P<0.001) 60min and 21h after administration, respectively. Plasma LH levels were elevated (p<0.05) at 20min but there was no significant increase found in urinary LH concentrations after injection. Intra-muscular injection of Synacthen® Depot (250μg) (n=3 males, 3 females) resulted in a significant increase (p<0.05) in plasma cortisol secretion 15min and in urinary cortisol concentrations 3h post injection, respectively. Sex-related differences in cortisol secretion were also reported in this study. These findings indicate that (1) urinary LH might not be an appropriate index for describing the reproductive status in captive male L. latifrons, and (2) the UTM and UCM assays appear to be suitable for the assessment of the testicular steroidogenic capacity and the adrenocortical activity in captive southern hairy-nosed wombats, respectively.
Publisher: Elsevier BV
Date: 07-2012
DOI: 10.1016/J.THERIOGENOLOGY.2012.02.005
Abstract: Effective sperm cryopreservation protocols are limited to a small number of marsupial species. In this study, postmortem gamete rescue (PMGR) epididymal sperm s les from Tasmanian devils (N=34) euthanized due to the fatal Devil Facial Tumor Disease were used to develop long-term sperm storage techniques for the species. Cryoprotectant toxicity associated with equilibration of sperm s les in a TEST yolk diluent (TEST 189 mM N-Tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, 85 mM Trizma base [Tris], 11 mM glucose, 20% vol/vol egg yolk pH 7.1, and 315.0±5.0 mOsm/kg) with a final concentration of 0.06 M trehalose, or 4%, 10%, and 18% vol/vol of either glycerol or dimethyl sulfoxide (DMSO), was examined over 12 h at 15 °C. Trehalose supplementation resulted in an immediate decline (P<0.05) of total motility. After 12 h, total motility was reduced (P<0.05) in treatments containing 18% glycerol, and 10% and 18% dimethyl sulfoxide. The effects of final glycerol concentration (4% and 10%), glycerol equilibration duration (10 min 1 h, or 3 h) prefreeze, freezing rate and the addition of 0.10 M lactose or a combination of 0.10 M lactose and 0.11 M raffinose were assessed during three experiments on the cryopreservation of postmortem gamete rescue s les in TEST. In all experiments, motility and viability were reduced (P<0.01 postthaw). S les cryopreserved in TEST supplemented with lactose or lactose with raffinose using a fast freezing rate (-8 °C/min from 4 to -40 °C, then -65 °C/min until -165 °C) produced the highest (P<0.05) postthaw motility (18.6±5.5% and 16.9±8.5%, respectively), which represented 35% to 48% retention of prefreeze motility. These results apparently were the best postthaw results of dasyurid sperm reported to date and will help lay the foundations for developing assisted reproductive technologies for marsupial species.
Publisher: Springer Science and Business Media LLC
Date: 10-04-2013
Publisher: Elsevier BV
Date: 05-2018
DOI: 10.1016/J.YGCEN.2018.01.021
Abstract: Although southern hairy-nosed wombats (SHN wombats Lasiorhinus latifrons) rarely breed in captivity, further knowledge of their reproductive physiology and behavior is likely to improve their breeding potential. This study examined the effect of seasonal variation and changes in social dynamics on the physiology and behavior of a captive population of male SHN wombats (n = 6). Seasonal changes in urinary testosterone metabolites (UTM), urinary cortisol metabolites (UCM), qualitative estimates of spermatorrhoea (QS), aggressive behavior and reproductive behavior were measured over an 11-month period. While there was no effect of month on QS (GLM ANOVA, P = 0.27), reproductive behavior (GLM ANOVA, P = 0.19) or aggressive behavior (Tukey pairwise comparisons), the secretion of UTM (GLM ANOVA, P = 0.051) was only marginally affected by season, compared to that reported for wild male SHN wombats. Mean UCM concentrations of July and August 2016 were significantly higher than those between October 2015 and January 2016 (Tukey pairwise comparisons). To examine social dynamics, two trials of animal positioning exchange with the enclosure system were implemented and behavioral data were examined for each trial over a six week period UTM, UCM and general behaviors (n = 27) were measured for each trial. Neither UTM nor UCM concentration varied significantly (P ≥ 0.45) before and after the exchanges. "Scratching" decreased at the group level following the animal exchange in both trials, suggesting reduction in self-grooming may be a behavioral response to novel stimuli. UCM and UTM concentrations were both positively correlated with "standing still" and "body rub" behaviors. This may be evidence of a hormonal control of a "freezing behavioral response" to external stimuli and marking behavior, respectively. As there was no evidence that changing the social dynamics affected reproductive or agonistic behavior or hormone concentrations, it was concluded that captive male wombats in this study showed reduced reproductive seasonality compared to wild wombats and that animal exchange resulted in a behavioral response to novel stimuli but was not sufficient to affect testosterone or cortisol secretion, within the context of our study.
Publisher: Elsevier BV
Date: 2010
DOI: 10.1016/J.ANIREPROSCI.2009.03.005
Abstract: The Julia Creek dunnart (Sminthopsis douglasi) is an endangered carnivorous marsupial belonging to the family Dasyuridae. This study investigated the oestrous cycle of this species in terms of its reproductive physiology and behaviour to explore more efficient methods of oestrus detection. Ten sexually mature captive female dunnarts were monitored daily at David Fleay Wildlife Park, Burleigh Heads, Australia, from mid September to late December 2006 for changes in urogenital cytology within the urine (0, 1+, 2+ and 3+), running wheel activity, body weight, uneaten food, faecal steroid metabolites (progesterone and oestradiol) and pouch development. Periods of increased running wheel activity were associated (p=0.004) with an increase in the proportion of cornified urogenital epithelial cells found in the urine periods of decreasing weight (p<0.001) and uneaten food (p<0.001) were also associated with changes in urogenital cytology but not to the point where they would be useful for oestrus detection. Between 60.3% and 92.0% of peak distances (confidence interval 95%) occurred when the epithelial cell index was 2+ or 3+. Only 15.5-37.5% of peak weights (CI: 95%) and 28.1-49.9% of incidences of uneaten food (CI: 95%) occurred when the epithelial cell index was 2+ or 3+. There was no significant difference in the mean length of the oestrous cycle when measured by urogenital cytology (mean+/-SD: 25.0+/-5.7 days n=20) or peak distance travelled (mean+/-SD: 25.4+/-5.7 days n=20). Changes in the concentration of oestradiol metabolites in Julia Creek Dunnart faeces were not useful in characterising the oestrous cycle. Wheel running activity declined markedly with increased faecal progestagen concentration. The majority of the pouch variables examined showed maximum development during the inter-oestrus period but as there was considerable variation between animals, the pouch was not considered a useful index of oestrus.
Publisher: Oxford University Press (OUP)
Date: 27-05-2019
DOI: 10.1093/BIOLINNEAN/BLZ072
Abstract: Polyandry, a common reproductive strategy in various animal species, has potential female benefits, which include enhanced offspring fitness. Benefits can be direct, such as reduced risk of male infanticide of offspring, or indirect, such as increased genetic ersity of offspring and the acquisition of ‘good genes’. Multiple paternity of litters has been recorded in numerous marsupial species but has not been reported in Tasmanian devils, Sarcophilus harrisii (Boitard). We investigated whether multiple paternity occurred in litters within a wild population of Tasmanian devils. Using major histocompatibility complex-linked and neutral microsatellite markers, the paternity of nine litters was analysed. We found multiple paternity in four out of nine litters and that yearling ( 1, 2 years old) male devils were siring offspring. This is the first record of multiple paternity and of male precocial breeding in wild Tasmanian devils. To date, there are no data relating to the subsequent survival of devils from single- vs. multiple-sired litters therefore, we do not know whether multiple paternity increases offspring survival in the wild. These results have implications for the Tasmanian devil captive insurance programme, because group housing can lead to multiple-sired litters, making the maintenance of genetic ersity over time difficult to manage.
Publisher: Elsevier BV
Date: 05-2020
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/ZO16088
Abstract: Whilst flehmen behaviour has been observed in some marsupials, including the southern hairy-nosed wombat (Lasiorhinus latifrons), it is unknown whether it, or other male-specific behaviours are exhibited differentially in response to the detection of oestrous females, which if proven, could assist in the detection of oestrus in breeding programs for captive southern hairy-nosed wombats. Six captive male southern hairy-nosed wombats were exposed to urine s les collected from a single female that was confirmed to be in oestrus and mid-pregnancy. Urine s les were presented to the males simultaneously and subsequent behaviours recorded for five minutes. There were no significant differences in the number of times flehmen behaviour was displayed in response to oestrous and non-oestrous urine s les (P = 0.577), the number of times the male sniffed each s le (P = 0.595), or the time spent investigating each urine s le (P = 0.414). Our results suggest that neither male flehmen behaviour nor any specific male-related precopulatory behaviour was associated with the olfaction of urine from a female in different stages of the oestrous cycle, and is thus unlikely to be a reliable management tool for the detection of oestrus.
Publisher: MDPI AG
Date: 28-04-2016
DOI: 10.3390/ANI6050030
Publisher: Elsevier BV
Date: 2023
Publisher: Elsevier BV
Date: 05-2012
DOI: 10.1016/J.YGCEN.2012.02.008
Abstract: Assessing reproductive status and monitoring reproductive rates is important in the effective management of vulnerable marine mammal species such as the dugong (Dugong dugon). Knowledge of the reproductive physiology of this species is limited, and determining reproductive parameters (e.g., sexual maturation, pregnancy, and reproductive senescence) has been restricted by a lack of non-lethal methods for assessing reproductive status in free-ranging in iduals. The aim of this study was to develop a method to identify pregnant in iduals in a wild dugong population. Using an enzymeimmunoassay, we quantified concentrations of fecal progesterone metabolites (fP) in 322 dugongs, including confirmed pregnant females (n=10), presumed non-pregnant adult females (n=25), juvenile females (n=24), subadult females (n=41), adult females of unknown pregnancy state (n=63), and males of all sizes (n=159). External body morphometrics of each dugong were measured, and confirmation of pregnancy in adult female dugongs was determined by ultrasonography or observation of subsequent neonates. Concentrations of fP were different between sexes and reproductive size classes (P<0.001), and ∼30-fold higher in confirmed pregnant dugongs (2017-7760 ng/g) compared to presumed non-pregnant females (30-221 ng/g), juvenile females (29-195 ng/g), and males (24-261 ng/g) (P<0.001). Body measures of maximum and anal girths, and teat length were all greater in confirmed pregnant females than presumed non-pregnant females (all P 1000 ng/g, body length ≥ 260 cm, maximum girth ≥ 215 cm, anal girth ≥ 126 cm, and teat length ≥ 5 cm long. In summary, analysis of fP concentrations in combination with body morphometrics may be used to diagnose pregnancy in free-ranging dugongs, and provides a new tool to monitor breeding rates of wild sirenian populations.
Publisher: Elsevier BV
Date: 06-2010
DOI: 10.1016/J.ANIREPROSCI.2010.01.006
Abstract: In order to develop a reliable method of oestrus detection in captive southern hairy-nosed (SHN) wombats, the reproductive behaviour of four groups of adult animals (1 male:2 female) was monitored using video surveillance and activity using movement-sensitive radio transmitters for a period of 12 months. During this time faecal s les were collected every 3 days and subsequently analysed for progesterone and oestradiol-17beta metabolites. In an attempt to induce and characterise oestrus-specific behaviour, each female was administered a subcutaneous injection of either 0.01 (n=2), 0.1 (n=4) or 0.2mg/kg (n=2) of oestradiol benzoate in one of two hormone trials. Remote video surveillance was an effective tool for detecting the reproductive behaviour of the captive SHN wombat. Courtship (n=426) and mating (n=46) was observed in five wombats and consisted of 13 distinctive behaviours in six consecutive phases: (1) investigation, (2) attraction, (3) chase, (4) restraint, (5) copulation and (6) recovery. Female sexual receptivity occurred at night and lasted for approximately only 13-h. Faecal progesterone metabolite analysis proved to be a reliable method for mapping oestrous cycle activity, but was not useful for the prediction of oestrus. Six out of the eight female wombats displayed periods of elevated progesterone secretion, corresponding to a mean (+/-SE) luteal phase of 20.9+/-1.1 days (n=23). Oestrous cycle length, defined as the interval between two successive luteal phases separated by a follicular phase was 31.8+/-1.1 days (n=12) and consisted of a follicular phase of 11.6+/-0.6 days (n=12). Changes in the secretion of faecal oestradiol-17beta metabolites provided little instructive information on oestrous cycle activity and were not associated with oestrus. Administration of oestradiol benzoate resulted in a spike of oestradiol-17beta metabolites in the faeces 3-4 days later, but was not dose dependent nor did it facilitate reproductive behaviour in either sex. Activity was not linked to key events in the oestrous cycle and appears not to be suitable as a method for detecting oestrus in the SHN wombat. We therefore recommend the use of 24-h video surveillance as the most reliable method for oestrus detection in captive SHN wombats.
Publisher: Aquatic Mammals Journal
Date: 15-09-2019
Publisher: Bioscientifica
Date: 05-2012
DOI: 10.1530/REP-11-0434
Abstract: Knowledge of male reproductive status and activity in free-ranging animals is vital to understanding reproductive patterns and population dynamics. Until now, almost all information regarding reproductive behavior of the dugong, a cryptic marine mammal, has relied on post-mortem examination. We examined the relationships between body length, tusk eruption (secondary sexual characteristic), seasonality, and group association on fecal testosterone metabolite concentrations in 322 free-ranging dugongs (159 males, 163 females) in subtropical Moreton Bay, Australia. Fecal testosterone concentrations demonstrated biologically meaningful differences in testicular activity between sexes and across reproductive/age classes, and were correlated with circulating concentrations in serum. Male dugongs have a pre-reproductive period that persists until a body length of 240 cm is achieved. Puberty apparently occurs between 240 and 260 cm body length when fecal testosterone levels increase fourfold ( ng/g) over juvenile levels, and is associated with tusk eruption. However, social maturity may be delayed until male dugongs are larger than 260 cm with well-developed tusks. In mature males, the lowest ( ng/g) fecal testosterone concentrations occur in the austral autumn months with maximal concentrations in September–October, coincident with the onset of a spring mating season. During spring, solitary mature males had fecal testosterone concentrations double those of mature males s led within groups, potentially suggesting a mating strategy involving roving of reproductively active males. This study demonstrates that single-point physiological data from in iduals across a population have value as indicators of reproductive processes. Our approach provides an efficacious non-lethal method for the census of reproductive status and seasonality in live male dugongs.
Publisher: Elsevier BV
Date: 04-2012
DOI: 10.1016/J.YGCEN.2012.01.011
Abstract: Numbers of wild Tasmanian devils are declining as a result of the fatal, transmissible Devil Facial Tumor Disease. A captive insurance population program has been initiated but current captive breeding rates are sub-optimal and therefore the goal of this project was to increase our understanding of the estrous cycle of the devil and elucidate potential causes of failed male-female pairings. Temporal patterns of fecal progestagen and corticosterone metabolite concentrations were examined for females (n=41) in three categories of reproductive status (successful: viable young, n=20 estrous cycles unsuccessful: paired with a male but no young confirmed, n=44 estrous cycles non-mated: no access to a male during estrus, n=8 estrous cycles) but substantial differences were not found. Females were more likely to produce pouch young if pairing with the male extended into late proestrus (P 0.05). Unsuccessful females had 1-3 estrous cycles within a single year. Successful females were predominantly wild-caught (17/19, 90%) and most produced young following the first estrous cycle of the season (18/20, 90%). Unsuccessful females were predominantly captive born (20/27, 74%) in this study. It is possible that a proportion of females that do not produce pouch young achieve conception but the timing of reproductive failure continues to be elusive in this species.
Publisher: Wiley
Date: 26-11-2013
DOI: 10.1111/AVJ.12125
Abstract: Stress can play a role in disease incidence in all species via immunosuppression and has been implicated as a contributing factor in significant infectious diseases of koalas. Faecal cortisol measurement may represent a non-invasive methodology for quantifying stress in koalas. We used an ACTH (adrenocorticotropic hormone) stimulation test (10 IU) to induce sustained secretion of cortisol, which was measured in serum s les from four koalas and subsequently it was attempted to locate a corresponding elevation in either cortisol or corticosterone measurements within the faeces. Although ACTH administration resulted in an elevation of serum cortisol for at least 4 h post injection, it was not possible to identify a corresponding peak in corticosterone or cortisol concentrations in extracts from the faeces, consistent with the known gut transit time of the koala. Faecal cortisol and corticosterone metabolites may not be reliable indices of acute changes in cortisol secretion in the koala and studies that attempt to use faecal cortisol as an index of stress will need to be interpreted with caution.
Publisher: Elsevier BV
Date: 04-2010
DOI: 10.1016/J.ANIREPROSCI.2009.10.001
Abstract: This study reports on the development and application of techniques used to assess the reproductive status of captive male southern hairy-nosed wombats (n=4) at Rockh ton Zoo. Initially, a GnRH agonist was used to establish a method for determining a reliable index of plasma and faecal testosterone secretion. Intra-muscular injection of buserelin (4 microg) resulted in an increase (P<0.05) in plasma and faecal testosterone concentration 90 min and 3 days after administration, respectively. Seasonal changes in faecal androgen, sperm production (spermatorrhoea) and testicular, prostatic and bulbourethral gland size were examined over a 18-month period, with prostate and bulbourethral gland cross-sectional areas being assessed by ultrasonography. Plasma testosterone secretion increased from early late winter and then decreased in spring (P<0.001) no seasonal variation (P=0.22) in faecal testosterone metabolite concentrations was apparent. Testicular volume showed no significant variation (P=0.29) over the s ling period. While there was no seasonal change (P=0.197, n=54) in prostate size, bulbourethral gland size increased in late-autumn, peaked in mid-winter and declined in early summer (P= or <0.001, n=55). Spermatozoa were found in the urine throughout the year. While, the captive population of SHN wombats at Rockh ton Zoo demonstrated significant changes in reproductive function, the extent of seasonality was less pronounced than that previously reported for wild populations in Southern Australia.
Publisher: Elsevier BV
Date: 06-2017
DOI: 10.1016/J.THERIOGENOLOGY.2017.02.013
Abstract: The synchrony and timing of reproductive events are crucially important factors to maximize in idual and offspring survival, especially in seasonal environments. To increase our understanding of the physiological basis of seasonality and the influence of associated environmental factors (maximum temperature, day length and rate of day length change associated with different latitudes) on reproduction in Tasmanian devils, we reviewed records and research data from captive facilities throughout Australia in comparison to those from a wild population study (1974-1987). Overall, breeding activity began 2 weeks earlier in the captive than the wild population (week 5.7 ± 0.6 versus week 7.7 ± 0.5 for devils entering into estrus during the first two week phase n = 24 and n = 23 respectively). If the timing of reproductive activity is considered against absolute day length rather than date, both the captive and wild populations displayed similar distributions (12.9 ± 0.7 h versus 13.0 ± 0.7 h respectively P < 0.01) confirming day length as a proximal cue involved in eliciting a physiological response to trigger seasonal reproductive activity regardless of location. Wild devils had a higher breeding success (75% n = 169 versus 43% n = 115) and larger litter size (3.4 ± 0.9 versus 2.8 ± 1.1 joeys per litter) than captive devils (P < 0.05). Mean maximum temperature at the onset of reproductive activity (P < 0.05) was higher for the captive than the wild population (28.1 ± 4.0 °C versus 22.3 ± 2.7 °C respectively). The drivers for reproductive success in captive Tasmanian devils are likely multifactorial, but our results suggest that elevated temperatures associated with shifts in breeding activity and geographical location should be examined further.
Publisher: Elsevier BV
Date: 10-2017
Publisher: CSIRO Publishing
Date: 2008
DOI: 10.1071/RD07206
Abstract: The present study reports novel aspects of the reproductive biology of the male common ringtail possum (Pseudocheirus peregrinus). Plasma testosterone was measured through a stimulation test using the gonadotrophin-releasing hormone agonist, buserelin. Following intra-muscular administration of buserelin, there was an increase (P 0.05) in testosterone concentration in the peripheral circulation 4 h later. Quantitative testicular histology of this species was described for the first time. Eight stages of the seminiferous epithelium cycle were identified in 10 possums and their relative frequency determined. Spermatozoa were recovered from the cauda epididymides of hemi-castrated possums and cryopreservation conducted in straws (6°C min–1) using final glycerol concentrations ranging between 2 and 20% in Tris-citrate egg yolk extender (v/v). Frozen straws were thawed and post-thaw motility, rate of motility, the percentage of live–dead spermatozoa and the percentage of sperm with swollen decondensed nuclei recorded. Similar to other marsupial sperm, common ringtail possum cauda epididymidal spermatozoa required high levels of glycerol (10–16%) in order to maintain post-thaw viability.
Publisher: CSIRO Publishing
Date: 2017
DOI: 10.1071/RD16511
Abstract: The aim of the present study was to develop a protocol for the successful cryopreservation of Saltwater crocodile spermatozoa. Sperm cells were frozen above liquid nitrogen vapour in phosphate-buffered saline (PBS) containing either 0.3 M trehalose, 0.3 M raffinose or 0.3 M sucrose and compared with glycerol (0.3–2.7 M). Although the highest levels of mean post-thaw motility were observed following cryopreservation in 0.3 M trehalose (7.6%) and 0.3 M sucrose (7.3%), plasma membrane integrity (PI) was best following cryopreservation in 2.7 M glycerol (52.5%). A pilot study then assessed the cytotoxicity of glycerol and sucrose prior to cryopreservation and revealed no loss of survival when spermatozoa were diluted in 0.68 M glycerol or 0.2–0.3 M sucrose once cryoprotectants were washed out with PBS or Biggers, Whitten and Whittingham medium containing sperm capacitation agents (BWWCAP). A final study refined the combined use of permeating (0.68 or 1.35 M glycerol) and non-permeating (0.2 or 0.3 M sucrose) cryoprotectants. Spermatozoa were cryopreserved in liquid nitrogen vapour at rates of approximately −21°C min−1 (fast freeze) or −6.0°C min−1 (slow freeze). Post-thaw survival was highest with a combination of 0.2 M sucrose and 0.68 M glycerol and when these cryoprotectants were washed out with BWWCAP, regardless of whether spermatozoa were frozen using a fast (motility 14.2 ± 4.7% PI 20.7 ± 2.0%) or slow (motility 12.0 ± 2.7% PI 22 ± 4%) cryopreservation rate.
Publisher: Elsevier BV
Date: 09-2011
DOI: 10.1016/J.THERIOGENOLOGY.2011.04.001
Abstract: The Tasmanian devil is suffering from a severe population decline due to the fatal Devil Facial Tumour Disease (DFTD). The development of assisted reproductive technologies such as AI and long-term sperm storage could facilitate genetic management of captive insurance populations. The aim of this study was to characterise semen s les collected post-mortem, and to develop a suitable diluent for short-term preservation of devil sperm. Low numbers of sperm (1.33 ± 0.85 × 10(6) sperm per male) were extracted from the epididymides of 17 males. Devil sperm s le characteristics such as concentration and morphology were similar to other dasyurids. The most commonly observed morphological abnormalities were midpiece separation, tail curling, and tail twisting (on the axial plane). Changes in motility occurred throughout the regions of the epididymis with (mean ± SD) 29.4 ± 16.8, 46.8 ± 13.6 and 29.4 ± 18.1% of sperm exhibiting motility, and 88.9 ± 11.4, 32.0 ± 24.3 and 0.1 ± 0.2% of motile sperm exhibiting forward progressive motility in the cauda, corpus and caput, respectively. Sperm from the cauda and corpus epididymis maintained 31.7 ± 26.6 and 80.6 ± 85.9%, respectively, of initial motility after 12 h at 15 °C in a TEST yolk buffer diluent. These findings provided new information regarding devil sperm biology and short-term sperm storage such information is necessary for future development of long-term sperm preservation methods in the Tasmanian devil.
Publisher: Elsevier BV
Date: 08-2007
DOI: 10.1016/J.ANIREPROSCI.2006.08.017
Abstract: Implementation of assisted breeding in the captive African wild dog is restricted by a current lack of knowledge on their reproductive physiology and the apparent difficulty of effectively manipulating the complex social dynamic of the pack in order to conduct reproductive procedures. In this study, we describe protocols for the safe and repeated capture and restraint of the African wild dog (n=7) as well as techniques for assessment of male reproductive function, semen collection and preservation. In a serendipitous finding, captive African wild dogs appeared to display significant seasonal change in male reproduction. Testicular volume and tone, spermatorrhea and the ability to collect semen by electroejaculation all increased significantly during late summer and then subsequently declined by early spring. While there were no detectable seasonal changes in testosterone concentration in the population as whole, the alpha-dominant male in both years of the study, had a highly elevated testosterone concentration compared to subordinate males. Semen collection by electroejaculation during the late summer was most effective in peri-pubertal males (15 months) when all seven electroejaculates were of adequate quality for cryopreservation. In the second breeding season (27 months), there were numerous changes in the pack hierarchy and electroejaculation was not as successful (3/7). The characteristics of electroejaculated semen collected in the breeding season are described for seven animals including the first descriptions and incidence of sperm abnormalities in the species. Semen (n=7) was frozen using a Tris-citrate fructose buffer and final egg yolk and glycerol concentration of 20% and 4%, respectively. Sperm were loaded into 0.25 mL straws, frozen in liquid nitrogen vapor and then thawed at 37 degrees C. Initial post-thaw survival of spermatozoa was encouraging (% motile: 31.8+/-5.8% rate: 2.8+/-0.3 % intact plasma membranes: 33.4+/-5.3% and the % of damaged acrosomes: 4.4+/-1.5%) but following 2 h incubation at 37 degrees C, post-thaw survival declined markedly.
Publisher: Elsevier BV
Date: 04-2017
DOI: 10.1016/J.YGCEN.2015.10.011
Abstract: Marsupial research, conservation, and management can benefit greatly from knowledge about glucocorticoid (GC) secretion patterns because GCs influence numerous aspects of physiology and play a crucial role in regulating an animal's response to stressors. Faecal glucocorticoid metabolites (FGM) offer a non-invasive tool for tracking changes in GCs over time. To date, there are relatively few validated assays for marsupials compared with other taxa, and those that have been published generally test only one assay. However, different assays can yield very different signals of adrenal activity. The goal of this study was to compare the performance of five different enzyme immunoassays (EIAs) for monitoring adrenocortical activity via FGM in 13 marsupial species. We monitored FGM response to two types of events: biological stressors (e.g., transport, novel environment) and pharmacological stimulation (ACTH injection). For each in idual animal and assay, FGM peaks were identified using the iterative baseline approach. Performance of the EIAs for each species was evaluated by determining (1) the percent of in iduals with a detectable peak 0.125-4.5days post-event, and (2) the biological sensitivity of the assay as measured by strength of the post-event response relative to baseline variability (Z-score). Assays were defined as successful if they detected a peak in at least 50% of the in iduals and the mean species response had a Z⩾2. By this criterion, at least one assay was successful in 10 of the 13 species, but the best-performing assay varied among species, even those species that were closely related. Furthermore, the ability to confidently assess assay performance was influenced by the experimental protocols used. We discuss the implications of our findings for biological validation studies.
Publisher: American Diabetes Association
Date: 15-04-2021
DOI: 10.2337/DC20-2676
Abstract: Obesity is an established risk factor for severe coronavirus disease 2019 (COVID-19), but the contribution of overweight and/or diabetes remains unclear. In a multicenter, international study, we investigated if overweight, obesity, and diabetes were independently associated with COVID-19 severity and whether the BMI-associated risk was increased among those with diabetes. We retrospectively extracted data from health care records and regional databases of hospitalized adult patients with COVID-19 from 18 sites in 11 countries. We used standardized definitions and analyses to generate site-specific estimates, modeling the odds of each outcome (supplemental oxygen/noninvasive ventilatory support, invasive mechanical ventilatory support, and in-hospital mortality) by BMI category (reference, overweight, obese), adjusting for age, sex, and prespecified comorbidities. Subgroup analysis was performed on patients with preexisting diabetes. Site-specific estimates were combined in a meta-analysis. Among 7,244 patients (65.6% overweight/obese), those with overweight were more likely to require oxygen/noninvasive ventilatory support (random effects adjusted odds ratio [aOR], 1.44 95% CI 1.15–1.80) and invasive mechanical ventilatory support (aOR, 1.22 95% CI 1.03–1.46). There was no association between overweight and in-hospital mortality (aOR, 0.88 95% CI 0.74–1.04). Similar effects were observed in patients with obesity or diabetes. In the subgroup analysis, the aOR for any outcome was not additionally increased in those with diabetes and overweight or obesity. In adults hospitalized with COVID-19, overweight, obesity, and diabetes were associated with increased odds of requiring respiratory support but were not associated with death. In patients with diabetes, the odds of severe COVID-19 were not increased above the BMI-associated risk.
Publisher: Elsevier BV
Date: 10-2009
DOI: 10.1016/J.THERIOGENOLOGY.2009.06.014
Abstract: Numerous reports on reproductive pathology in all rhinoceros species illustrate the abundance of female infertility in captive populations. In infertile rhinoceroses, oocyte collection and embryo production could represent the best remaining option for these animals to reproduce and to contribute to the genetic pool. We report here on superstimulation, repeated oocyte recovery, and attempted in vitro fertilization (IVF) in white and black rhinoceroses. Four anestrous rhinoceroses (two white, two black) with unknown follicular status were treated with gonadotropin-releasing hormone analogue, deslorelin acetate, for 6 to 7 d. Number and size of follicles in superstimulated females was significantly higher and larger compared with those in nonstimulated anestrous females (n=9). Ovum pick-up was achieved by transrectal ultrasound-guided follicle aspiration. Up to 15 follicles were aspirated per ovary. During six ovum pick-ups, a total of 29 cumulus-oocyte complexes (COCs) were harvested with a range of 2 to 9 COCs per collection. No postsurgical complications were noted on the rhinoceros ovaries using this minimally invasive approach. Various in vitro maturation (IVM) and IVF protocols were tested on the collected COCs. Despite the low total number of COCs available for IVM and IVF in this study, we can report the first rhinoceros embryo ever produced in vitro. The production of a 4-cell embryo demonstrated the potential of transrectal ultrasound-guided oocyte recovery as a valuable tool for in vitro production of rhinoceros embryos from otherwise infertile females.
Start Date: 2008
End Date: 2008
Funder: SeaWorld and Busch Gardens Conservation Fund
View Funded ActivityStart Date: 2007
End Date: 2009
Funder: Morris Animal Foundation
View Funded ActivityStart Date: 2017
End Date: 2017
Funder: Cass Foundation
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