@article{koester_maly_putman_edwards_meeks_crosier_2022, title={An Investigation of Ovarian and Adrenal Hormone Activity in Post-Ovulatory Cheetahs (Acinonyx jubatus)}, volume={12}, ISSN={["2076-2615"]}, DOI={10.3390/ani12070809}, abstractNote={Simple Summary More than three decades of scientific study have been unable to determine the etiology of reproductive issues in cheetahs under human care. The reproduction of cheetahs in zoological facilities has never been self-sustaining, and the differences between females who establish pregnancy and those that do not remain poorly understood. The objective of this study was to examine and compare ovarian and adrenal hormones post-ovulation in pregnant and non-pregnant animals to better understand female physiology after natural breeding or artificial insemination, and determine what may be contributing to the frequent lack of success. The authors also sought to validate a urinary progestagen assay to assist with pregnancy detection. Although fecal glucocorticoid metabolites among pregnant and non-pregnant groups were not different, samples from the third trimester in pregnant animals were higher than at any other time. Additionally, glucocorticoids were higher, and estrogens tended to be lower in samples from pregnant females that gave birth to singletons, than those that had multi-cub litters. As a supplementary benefit, this is the first time urinary progestagens have been measured and have been able to distinguish pregnant and non-pregnant cheetahs. The results provide first-time insights into ovarian and adrenal hormonal events surrounding ovulation and pregnancy detection in cheetahs. Abstract Cheetahs have been the subject of reproductive study for over 35 years, yet steroid hormone activity remains poorly described after ovulation. Our objective was to examine and compare fecal progestagen (fPM), estrogen (fEM), and glucocorticoid (fGM) metabolite concentrations post-ovulation in pregnant and non-pregnant animals to better understand female physiology (1) during successful pregnancy, (2) surrounding frequent non-pregnant luteal phases, and (3) after artificial insemination (AI) to improve the low success rate. Secondarily, the authors also validated a urinary progestagen metabolite assay, allowing pregnancy detection with minimal sample collection. Fecal samples were collected from 12 females for ≥2 weeks prior to breeding/hormone injection (the PRE period) through 92 days post-breeding/injection. Samples were assessed for hormone concentrations using established enzyme immunoassays. Urine samples were collected for 13 weeks from 6 females after natural breeding or AI. There were no differences among groups in fGM, but in pregnant females, concentrations were higher (p < 0.01) in the last trimester than any other time. For pregnant females that gave birth to singletons, fGM was higher (p = 0.0205), but fEM tended to be lower (p = 0.0626) than those with multi-cub litters. Our results provide insight into the physiological events surrounding natural and artificially stimulated luteal activity in the cheetah.}, number={7}, journal={ANIMALS}, author={Koester, Diana C. and Maly, Morgan A. and Putman, Sarah and Edwards, Katie L. and Meeks, Karen and Crosier, Adrienne E.}, year={2022}, month={Apr} }
 @article{maly_edwards_farin_koester_crosier_2021, title={Assessing puberty in female cheetahs (Acinonyx jubatus) via faecal hormone metabolites and body weight}, ISSN={["1448-5990"]}, DOI={10.1071/RD21169}, abstractNote={With fewer than 7500 cheetahs remaining in the wild, ex situ cheetah populations serve as an insurance policy against extinction and a resource to study species' biology. This study aimed to identify the age of pubertal onset in ex situ female cheetahs using non-invasive faecal steroid hormone monitoring and body weights. Faecal samples from nine female cheetahs were collected two to three times weekly from 2 to 36months of age and body weights were recorded every 3months. Faecal oestrogen metabolites (FOM) and faecal glucocorticoid metabolites (FGM) were analysed using enzyme immunoassays and samples were categorised into 6-month intervals to compare endocrine characteristics. Faecal hormone and body weight data were analysed using generalised linear mixed models. Age was a significant predictor of mean and baseline FOM concentrations, number of FOM peaks, mean and maximum FOM peak concentrations and the number of cycles. Female cheetahs aged 24-30months exhibited a marked rise in mean FOM concentration and the number of FOM peaks and cycles increased with age until 24-30months. Females attained adult body weight by 21months of age. Mean and baseline FGM concentrations were highest at the 0-6 and 12-18months of age groups and did not follow the same FOM patterns. Based on body weight data, the FOM concentrations and peak patterning, females were considered pubertal from 24 to 30months of age. Characterisation of cheetah puberty has direct and significant implications for the improvement of management and reproductive success of cheetahs under human care. This information is particularly informative for identifying important windows of development, littermate dispersal and breeding introductions.}, journal={REPRODUCTION FERTILITY AND DEVELOPMENT}, author={Maly, Morgan A. and Edwards, Katie L. and Farin, Charlotte E. and Koester, Diana C. and Crosier, Adrienne E.}, year={2021}, month={Nov} }
 @article{crosier_lamy_bapodra_rapp_maly_junge_haefele_ahistus_santiestevan_comizzoli_2020, title={First Birth of Cheetah Cubs from In Vitro Fertilization and Embryo Transfer}, volume={10}, ISSN={["2076-2615"]}, DOI={10.3390/ani10101811}, abstractNote={Simple Summary Although the cheetah is the most studied of all wild felid species, reproduction of cheetahs in zoological settings has never been self-sustaining. A large proportion (~30%) of the Association of Zoos and Aquariums population is excluded from breeding due to advanced age, health, behavior, or management issues. Development of assisted reproductive technologies (ARTs) to enable the genetic contribution of sub-fertile individuals is now a priority research and management focus. We have previously demonstrated that aging females produce eggs that have the same developmental competence as young females. The objective of the present study was to produce embryos in vitro from older donor oocytes and transfer them into younger recipients to obtain pregnancies and live births. Good quality oocytes were collected from three synchronized donors, fertilized in vitro with frozen-thawed semen, and cultured for two days. Resulting embryos were transferred into the oviduct of three synchronized recipients. Pregnancies were monitored via fecal levels of progestogens, ultrasonography, and radiography. Two cubs were born naturally after 90 days of gestation, representing the first cheetah births resulting from the transfer of embryos produced in vitro. Abstract Approximately 30% of the Association of Zoos and Aquariums cheetah population (~350 total animals) is unlikely to breed naturally due to advanced age, health, or behavioral issues. Aging cheetah females (≥9 y old) are unlikely to become pregnant via natural breeding if they are nulliparous. We previously demonstrated that oocytes recovered from aged females were of similar quality compared with those recovered from younger females (2–8 y old). We hypothesize that transfer of 4–8 cell embryos produced by in vitro fertilization with oocytes from old donors could result in pregnancy after transfer into younger recipients. Female cheetahs (n = 3 aging donors and n = 3 young recipients) received 300 IU equine Chorionic Gonadotropin (eCG) and 3000 IU Luteinizing Hormone (LH) while fecal metabolites of estrogens and progestogens were closely monitored. At 28 h post-LH injection, oocytes were aspirated laparoscopically from donors and inseminated in vitro with cryopreserved sperm. After 48 h of in vitro culture, resulting embryos (4–8 cells) were transferred into the oviducts of recipient females. Pregnancy was confirmed in one recipient via ultrasound 32 days after transfer and by radiograph 62 days after transfer. Two cubs were born naturally after 90 days of gestation, representing the first cheetah births resulting from transfer of embryos produced in vitro.}, number={10}, journal={ANIMALS}, author={Crosier, Adrienne E. and Lamy, Julie and Bapodra, Priya and Rapp, Suzi and Maly, Morgan and Junge, Randy and Haefele, Holly and Ahistus, Jason and Santiestevan, Jenny and Comizzoli, Pierre}, year={2020}, month={Oct} }
 @article{maly_edwards_farin_koester_crosier_2018, title={Assessing puberty in ex situ male cheetahs (Acinonyx jubatus) via fecal hormone metabolites and body weights}, volume={268}, ISSN={["1095-6840"]}, DOI={10.1016/j.ygcen.2018.07.011}, abstractNote={Cheetahs are one of the most heavily studied felid species, with numerous publications on health, disease, and reproductive physiology produced over the last 30 years. Despite this relatively long history of research, there is a paucity of crucial biological data, such as pubertal onset, which has direct and significant applications to improved management of ex situ cheetah populations. This study aimed to determine age of pubertal onset in ex situ male cheetahs using non-invasive fecal steroid hormone monitoring and body weights. Fecal samples from 12 male cheetahs from four institutions were collected 2–3 times weekly from 1 to 42 months of age. Fecal androgen and glucocorticoid metabolites were analyzed using enzyme immunoassays previously validated for use with cheetah feces. Animal body weights were recorded monthly. Fecal hormone and body weight data were analyzed using generalized linear mixed models. Androgen concentrations exhibited an increase to levels similar to those observed in adult males by 18–24 months of age, and males attained adult body weights by 21 months of age. Based on these weight data and the initial increase in androgens toward adult concentrations, males were considered pubertal from 18 to 24 months of age. Glucocorticoid concentrations and amplitude of concentration over baseline were also increased during this period. Knowledge about the physiological changes associated with puberty is useful for management and improving reproductive success of cheetah populations under human care, particularly for determining timing of litter separation from dam, littermate dispersal and when to introduce potential breeding pairs.}, journal={GENERAL AND COMPARATIVE ENDOCRINOLOGY}, author={Maly, Morgan A. and Edwards, Katie L. and Farin, Charlotte E. and Koester, Diana C. and Crosier, Adrienne E.}, year={2018}, month={Nov}, pages={22–33} }