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Coral reefs are facing a crisis as the frequency of bleaching events caused by ocean warming increases, resulting in the death of corals on reefs around the world. The subsequent loss of genetic diversity and biodiversity can diminish the ability of coral to adapt to the changing climate, so efforts to preserve existing diversity are essential to maximize the resources available for reef restoration now and in the future. The most effective approach to secure genetics long-term is cryopreservation and biobanking, which permits the frozen storage of living samples at cryogenic temperatures in liquid nitrogen indefinitely. Cryopreservation of coral sperm has been possible since 2012, but the seasonal nature of coral reproduction means that biobanking activities are restricted to just a few nights per year when spawning occurs. Improving the efficiency of coral sperm processing and cryopreservation workflows is therefore essential to maximizing these limited biobanking opportunities. To this end, we set out to optimize cryopreservation processing pathways for coral sperm by building on existing technologies and creating a semi-automated approach to streamline the assessment, handling, and cryopreservation of coral sperm. The process, which combines computer-assisted sperm analysis, barcoded cryovials, and a series of linked auto-datasheets for simultaneous editing by multiple users, improves the efficiency of both sample processing and metadata management in the field. Through integration with cross-cutting research programs such as the Reef Restoration and Adaptation Program in Australia, cryopreservation can play a crucial role in large-scale reef restoration programs by facilitating the genetic management of aquaculture populations, supporting research to enhance thermal tolerance, and preventing the extinction of coral species. The described procedures will be utilized for coral cryopreservation and biobanking practitioners on reefs worldwide and will provide a model for the transition of cryopreservation technologies from research laboratories to large-scale applications.
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Antozoos , Acuicultura , Bancos de Muestras Biológicas , Criopreservación , Espermatozoides , Antozoos/fisiología , Criopreservación/métodos , Animales , Masculino , Acuicultura/métodos , Espermatozoides/fisiología , Espermatozoides/citología , Flujo de Trabajo , Preservación de Semen/métodos , Arrecifes de CoralRESUMEN
Polar bears (Ursus maritimus) face a number of challenges that threaten the survival of the species. Captive breeding represents one essential facet of species conservation, but aspects of the polar bear's reproductive physiology, such as follicle maturation, coitus-induced ovulation, and pseudopregnancy, are poorly characterized and present challenges for enhancing natural reproductive success and the application of advanced reproductive techniques. Due to the absence of a reliable transrectal or transabdominal ultrasound method for ovarian examination in the species, the ovaries of two adult female polar bears were examined laparoscopically to evaluate the feasibility of surgical access to the ovaries, oviduct, and uterus. The minimally invasive procedure was easily and rapidly performed in both bears and all procedures. Direct visual assessment of the ovary was possible after dissection of a fatty bursal sac, which completely enclosed the ovaries. In the second bear, laparoscopic manipulation of the ovary to draw it closer to the body wall enabled transcutaneous ultrasound. Laparoscopy may be a valuable tool to aid in the application of advanced reproductive technologies in polar bears.
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The cryopreservation and storage of gametes (biobanking) can provide a long-term, low-cost option for the preservation of population genetic diversity and is particularly impactful when applied to manage selective breeding within conservation breeding programs (CBPs). This study aimed to develop a sperm cryopreservation protocol for the critically endangered Booroolong frog (Litoria booroolongensis) to capture founder genetics within the recently established (est. 2019) CBP for this species. Hormone-induced sperm release was achieved using established protocols, and spermic urine samples were collected over a 6-h period. Pooled spermic urine samples (n = 3 males) were divided equally between two cryoprotectant (CPA) treatments and diluted by 1:5 (sperm:CPA) with either 15% (v/v) dimethyl sulfoxide + 1% (w/v) sucrose in simplified amphibian Ringer's (SAR; CPAA) or 10% (v/v) dimethylformamide + 10% (w/v) trehalose dihydrate in SAR (CPAB). The samples were cryopreserved in 0.25 mL straws using either a programmable freezer (FrA) or an adapted dry shipper method (FrB). The thawed samples were activated via dilution in water and assessed for viability and motility using both manual assessment and computer-assisted sperm analysis (CASA; 0 h, 0.5 h post-thaw). Upon activation, the survival and recovery of motility (total motility, forward progression and velocity) of cryopreserved sperm suspensions were higher for sperm preserved using FrB than FrA, regardless of CPA composition. This work supports our long-term goal to pioneer the integration of biobanked cryopreserved sperm with population genetic management to maximize restoration program outcomes for Australian amphibian species.
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Multidisciplinary approaches to conserve threatened species are required to curb biodiversity loss. Globally, amphibians are facing the most severe declines of any vertebrate class. In response, conservation breeding programs have been established in a growing number of amphibian species as a safeguard against further extinction. One of the main challenges to the long-term success of conservation breeding programs is the maintenance of genetic diversity, which, if lost, poses threats to the viability and adaptive potential of at-risk populations. Integrating reproductive technologies into conservation breeding programs can greatly assist genetic management and facilitate genetic exchange between captive and wild populations, as well as reinvigorate genetic diversity from expired genotypes. The generation of offspring produced via assisted fertilisation using frozen-thawed sperm has been achieved in a small but growing number of amphibian species and is poised to be a valuable tool for the genetic management of many more threatened species globally. This review discusses the role of sperm storage in amphibian conservation, presents the state of current technologies for the short-term cold storage and cryopreservation of amphibian sperm, and discusses the generation of cryo-derived offspring.
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Reproductive technologies (RTs) can assist integrated conservation breeding programs to attain propagation targets and manage genetic diversity more effectively. While the application of RTs to enhance the conservation management of threatened amphibians has lagged behind that of other taxonomic groups, a recent surge in research is narrowing the divide. The present study reports on the first application of RTs (hormone-induced spawning, hormone-induced sperm-release, and sperm cryopreservation) to the critically endangered Baw Baw frog, Philoria frosti. To determine the effect of hormone therapy on spawning success, male-female pairs were administered either 0 µg/g gonadotropin-releasing hormone agonist (GnRHa), 0.5 µg/g GnRHa, or 0.5 µg/g GnRHa + 10 µg/g metoclopramide (MET) (n = 6-7 pairs/treatment), and the number of pairs ovipositing, total eggs, and percent fertilisation success were quantified. To determine the effect of hormone therapy on sperm-release and to establish the peak time to collect sperm post-hormone administration, males were administered 0 IU/g (n = 4), or 20 IU/g hCG (n = 16). Total sperm, sperm concentration, and percent viability were quantified at 0, 2, 4, 6, 8, 10, and 12 h post-hormone administration. Overall, the percentage of pairs ovipositing was highest in the GnRHa + MET treatment, with 71% of pairs ovipositing, compared to 57% and 33% of pairs in the GnRHa and control treatments, respectively. The quantity of sperm released from males in response to hCG peaked at 4 h post-hormone administration, though it remained high up to 12 h. The percent sperm viability also peaked at 4 h post-administration (94.5%), exhibiting a steady decline thereafter, though viability remained above 77% throughout the 12 h collection period. The remaining sperm samples (n = 22) were cryopreserved using established protocols and biobanked for long-term storage and future conservation applications. The mean post-thaw sperm viability was 59%, and the percent total motility was 17%. The results from this preliminary study will direct further applications of RTs to the critically endangered Baw Baw frog to assist with species recovery.
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Managed breeding programs are an important tool in marsupial conservation efforts but may be costly and have adverse genetic effects in unavoidably small captive colonies. Biobanking and assisted reproductive technologies (ARTs) could help overcome these challenges, but further demonstration of their potential is required to improve uptake. We used genetic and economic models to examine whether supplementing hypothetical captive populations of dibblers (Parantechinus apicalis) and numbats (Myrmecobius fasciatus) with biobanked founder sperm through ARTs could reduce inbreeding, lower required colony sizes, and reduce program costs. We also asked practitioners of the black-footed ferret (Mustela nigripes) captive recovery program to complete a questionnaire to examine the resources and model species research pathways required to develop an optimized biobanking protocol in the black-footed ferret. We used data from this questionnaire to devise similar costed research pathways for Australian marsupials. With biobanking and assisted reproduction, inbreeding was reduced on average by between 80% and 98%, colony sizes were on average 99% smaller, and program costs were 69- to 83-fold lower. Integrating biobanking made long-standing captive genetic retention targets possible in marsupials (90% source population heterozygosity for a minimum of 100 years) within realistic cost frameworks. Lessons from the use of biobanking technology that contributed to the recovery of the black-footed ferret include the importance of adequate research funding (US$4.2 million), extensive partnerships that provide access to facilities and equipment, colony animals, appropriate research model species, and professional and technical staff required to address knowledge gaps to deliver an optimized biobanking protocol. Applied research investment of A$133 million across marsupial research pathways could deliver biobanking protocols for 15 of Australia's most at-risk marsupial species and 7 model species. The technical expertise and ex situ facilities exist to emulate the success of the black-footed ferret recovery program in threatened marsupials using these research pathways. All that is needed now for significant and cost-effective conservation gains is greater investment by policy makers in marsupial ARTs.
Los programas de reproducción controlada son una herramienta importante para los esfuerzos de conservación de marsupiales, aunque pueden resultar costosos y tener efectos genéticos adversos en las colonias cautivas incapaces de aumentar en tamaño. Los biobancos y las tecnologías de reproducción asistida (TRA) podrían ayudar a superar estos problemas, pero es necesario seguir demostrando su potencial para mejorar su adopción. Utilizamos modelos genéticos y económicos para analizar si la introducción de esperma fundador proveniente de biobancos mediante tecnologías de reproducción asistida a poblaciones cautivas hipotéticas de los marsupiales Parantechinus apicalis y Myrmecobius fasciatus podría reducir la endogamia, disminuir el tamaño efectivo de las colonias y reducir el costo de los programas. También pedimos a los profesionales del programa de recuperación en cautiverio del hurón de patas negras (Mustella nigripes) que respondieran un cuestionario para analizar los recursos y los métodos de investigación de las especies modelo necesarias para desarrollar un protocolo de biobanco optimizado para el hurón de patas negras. Utilizamos los datos de este cuestionario para diseñar métodos de investigación con costos similares para los marsupiales australianos. Con el biobanco y la reproducción asistida, la endogamia se redujo en promedio entre un 80 y un 98%, el tamaño de las colonias fue en promedio un 99% más pequeño y los costos del programa entre 69 y 83 veces menores. La integración del biobanco posibilitó los objetivos de retención genética en cautiverio a largo plazo en marsupiales (90% de heterocigosidad de la población de origen durante un mínimo de 100 años) dentro de un marco realista de costos. Entre el aprendizaje extraído del uso de la tecnología de biobancos que contribuyó a la recuperación del hurón de patas negras figuran la importancia de una financiación adecuada de la investigación (4.2 millones de dólares), colaboraciones profundas que faciliten el acceso a instalaciones y equipos, colonias de animales, especies modelo adecuadas para la investigación y el personal profesional y técnico necesario para abordar las lagunas de conocimiento y ofrecer un protocolo optimizado para los biobancos. Una inversión en investigación aplicada de 133 millones de dólares australianos para la investigación de los marsupiales podría proporcionar protocolos de biobancos para 15 de las especies de marsupiales australianos en mayor riesgo y 7 especies modelo. Existen los conocimientos técnicos y las instalaciones ex situ para emular el éxito del programa de recuperación del hurón de patas negras en marsupiales amenazados utilizando estas vías de investigación. Ahora sólo se necesita una mayor inversión por parte de los responsables políticos de las TRA para marsupiales para obtener beneficios de conservación significativos y rentables.
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Conservación de los Recursos Naturales , Marsupiales , Animales , Masculino , Bancos de Muestras Biológicas , Marsupiales/genética , Hurones , Semen , AustraliaRESUMEN
To gain more knowledge about the influence of hormone regulation on follicle development, ovarian ultrasounds were performed, and urinary hormone profiles were determined in ovulating and non-ovulating female bottlenose dolphins (n = 15) following estrus synchronization with altrenogest. Ovarian ultrasounds were conducted daily, post synchronization to describe follicular recruitment in relationship to the endocrine profile. Follicle sizes were grouped into very small (VSM), small (SM), medium (MD) and large (LG). In ovulating females, two follicular waves were identified, and follicular deviation towards establishing a dominant follicle only occurred during the second wave. For non-ovulating females, only the first wave was observed. For all urinary hormones, the non-ovulating group presented significantly lower concentrations of follicle stimulating hormone (uFSH), luteinizing hormone (uLH), estrone conjugates (uE1-C) and estriol (uE3) but similar progestagen and cortisol concentrations compared to the ovulating group. Concentrations of uE1-C and uE3 and numbers of MD and LG follicles significantly (P < 0.05) increased, while uFSH concentrations significantly (P < 0.05) decreased as ovulation approached. Urinary LH significantly increased concurrently with increasing numbers of LG follicles and decreasing numbers of SM follicles. The characterization of follicular development and its relationship with hormone assessments complements our understanding of follicular recruitment post-synchronization in bottlenose dolphins and provides new information concerning differences between ovulating and non-ovulating females in response to an estrous synchronization protocol.
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Zoo and wildlife hospital networks are set to become a vital component of Australia's contemporary efforts to conserve the iconic and imperiled koala (Phascolarctos cinereus). Managed breeding programs held across zoo-based networks typically face high economic costs and can be at risk of adverse genetic effects typical of unavoidably small captive colonies. Emerging evidence suggests that biobanking and associated assisted reproductive technologies could address these economic and genetic challenges. We present a modelled scenario, supported by detailed costings, where these technologies are optimized and could be integrated into conservation breeding programs of koalas across the established zoo and wildlife hospital network. Genetic and economic modelling comparing closed captive koala populations suggest that supplementing them with cryopreserved founder sperm using artificial insemination or intracytoplasmic sperm injection could substantially reduce inbreeding, lower the required colony sizes of conservation breeding programs, and greatly reduce program costs. Ambitious genetic retention targets (maintaining 90%, 95% and 99% of source population heterozygosity for 100 years) could be possible within realistic cost frameworks, with output koalas suited for wild release. Integrating biobanking into the zoo and wildlife hospital network presents a cost-effective and financially feasible model for the uptake of these tools due to the technical and research expertise, captive koala colonies, and ex situ facilities that already exist across these networks.
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Artificial reproduction involves collection and handling of gametes in a way that secures their quality and maximizes the fertilization outcome. In addition to initial sperm quality, numerous steps can affect the final result of fertilization, from the sperm collection process until gamete mixing (or co-incubation) when the spermatozoon enters or fuses with the oocyte. In this review, we summarize the whole process of sperm handling, from collection until fertilization for fish, penaeid shrimp, bivalve mollusks and marine mammals. To obtain sperm from captive animals, techniques vary widely across taxa, and include stripping by abdominal massage or testis surgical removal in fish, spermatophore collection in penaeid shrimps, gonadal scarification or temperature shock in bivalve mollusks, and voluntary collection via positive reinforcement in mammals. In most cases, special care is needed to avoid contamination by mucus, seawater, urine, or feces that can either activate sperm motility and/or decrease its quality. We also review techniques and extender solutions used for refrigerated storage of sperm across the aforementioned taxa. Finally, we give an overview of the different protocols for in vivo and in vitro fertilization including activation of sperm motility and methods for gamete co-incubation. The present study provides valuable information regarding breeder management either for animal production or species conservation.
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Organismos Acuáticos/fisiología , Manejo de Especímenes/veterinaria , Recuperación de la Esperma/veterinaria , Animales , Crassostrea , Peces , Inseminación Artificial/veterinaria , Masculino , Mamíferos , Penaeidae , Preservación de Semen/veterinaria , Manejo de Especímenes/métodosRESUMEN
Relatively little is known about elasmobranch reproductive physiology compared to other species. An increased understanding of elasmobranch reproduction would improve the success of captive breeding and may aid in situ conservation efforts by reducing demand for wild-caught individuals. The reproductive status of seven adult female white-spotted bamboo sharks (Chiloscyllium plagiosum) (WSB) was monitored via coelomic ultrasonography and analysis of plasma biochemistry and steroid hormones over 6 months. Based on ultrasonic findings, females were categorized at each blood collection time point as: no follicular activity (INACTIVE), follicles but no eggs present (ACTIVE-OVARY), and eggs present within the oviduct (ACTIVE-OVIDUCT). Triglyceride concentrations were greater for those with the ACTIVE-OVARY (75.98 mg/dL; CI 61.81-90.15 mg/dL) and ACTIVE-OVIDUCT (87.0 mg/dL; CI 70.20 to 103.81 mg/dL) categories than INACTIVE (51.81 mg/dL; CI 37.07-66.54 mg/dL) category. No significant differences were observed for PCV, total solids, calcium, phosphorus, iron or progesterone. Estradiol concentrations were less for the INACTIVE (0.15 ng/ml; CI 0.08 to 0.25 ng/ml) than ACTIVE-OVARY (0.63 ng/ml; CI 0.42 to 0.88 ng/ml) and ACTIVE-OVIDUCT (0.92 ng/ml; CI 0.64-1.26 ng/ml) category. Testosterone concentrations differed among reproductive states, being greater with the INACTIVE (0.22 ng/ml; CI 0.13 to 0.37 ng/ml) and peaking in the ACTIVE-OVIDUCT (2.12 ng/ml; CI 1.25-3.60 ng/ml) state. The ultrasonic technique was performed in a standardized manner, and the anatomy was validated via opportunistic post-mortem examinations and MRI. Using the described diagnostic techniques, reproductive status in WSB can be routinely monitored, and findings have implications for improving the success of captive breeding efforts in other elasmobranch species.
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Reproducción/fisiología , Tiburones/fisiología , Animales , Femenino , Ovario/ultraestructura , Óvulo , ProgesteronaRESUMEN
The circulating pattern of immunoreactive relaxin and progestagens based on monthly and gestational stage (early, mid, late) profiles were determined during pregnancies that resulted in live calves (LIVE, nâ¯=â¯30), stillbirths (STILLB, nâ¯=â¯3), abortions (ABORT, nâ¯=â¯5) and presumptive false pregnancies (FALSE, nâ¯=â¯8), and during the follicular (nâ¯=â¯34) and luteal phase (nâ¯=â¯58). Monthly LIVE relaxin concentrations steadily increased during gestation, but values did not significantly exceed those of the luteal phase until 9â¯months prior to parturition, peaking during the final month at 2356â¯ng/ml. Relaxin surged (Pâ¯<â¯0.05) during the final week of gestation (36,397â¯ng/ml), undergoing a 3 and 9-fold increase compared with concentrations in the preceding two weeks, respectively. Monthly relaxin production did not differ among each reproductive state with the exception of months-13-16 where concentrations were higher (Pâ¯<â¯0.001) for STILLB than LIVE. Relaxin concentration was reduced (Pâ¯<â¯0.0001) by 849% in placental versus maternal serum collected within 1â¯day of labor. Mid- and late-pregnancy progestagen concentrations were lower for FALSE (Pâ¯<â¯0.001) compared with STILLB and LIVE. Late pregnancy progestagen concentrations were reduced for FALSE (Pâ¯<â¯0.05) and ABORT (Pâ¯<â¯0.02) compared with LIVE and STILLB. Monthly progestagen production in ABORT tended to be lower than LIVE across a range of gestational months (Months 2, 7, 8, 11) but this difference only became significant during months 14 and 15. Results indicate that relaxin is primarily produced by the CL during pregnancy, and that concentrations could not be used to differentiate from non-pregnant females until the final 6â¯months of gestation. In addition, as would be expected from a primarily CL product, relaxin cannot be used to detect abnormal pregnancies. Conversely, progestagens, which are produced by both the placenta and CL can be used to differentiate FALSE from normal pregnancy and may be useful indicators of fetal health in the killer whale.
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Pérdida del Embrión/sangre , Preñez/sangre , Progestinas/sangre , Relaxina/sangre , Orca/sangre , Animales , Femenino , Parto/sangre , Circulación Placentaria , Embarazo , Progesterona/sangre , Reproducibilidad de los Resultados , ReproducciónRESUMEN
In the seminal plasma of terrestrial mammalian species known as induced (e.g., camels) and spontaneous (e.g., cattle) ovulators, an ovulation-inducing factor (OIF) with a protein structure similar to beta-nerve growth factor (ß-NGF) has been identified. Detection of an OIF/NGF in the seminal plasma of cetaceans would have both basic and applied implications in reproductive biology and conservation management programs. A preliminary evaluation was conducted to characterize the distribution and abundance of seminal plasma proteins in aquarium-based belugas and a Pacific white-sided and bottlenose dolphin. Initially, SDS-PAGE was used with 50 µg of total protein for separation; thereafter, Western immunoblot was used with anti-NGF. In addition to odontocete seminal plasma, a purified fraction of llama seminal plasma (100 ng protein) and an extract of mouse brain (20 µg total protein) were included as positive controls for NGF. Within the two belugas, visual inspection of the protein bands indicated similar distribution and intensity. However, among the belugas and Pacific white-sided and bottlenose dolphins there was more diversity than similarity in the distribution and abundance of seminal plasma proteins. While immunoreactivity of NGF was distinctly evident in the llama and mouse positive controls, there was no visual reactivity in any of the odontocete samples. These preliminary results provide novel information indicating more homogeneity within and heterogeneity among seminal plasma proteins of ondentocetes. Although NGF was not immunologically detected, future studies are required to address the apparent limitations of immuno-detection of NGF, especially if the post-translational form of ß-NGF is in low abundance in the seminal plasma of belugas and Pacific white-sided and bottlenose dolphins.
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The secretory patterns of testosterone (T), androstenedione (A4), dehydroepiandrosterone (DHEA), cortisol (C), and corticosterone (Co) were characterized throughout 28 normal pregnancies until two-months post-partum in eleven killer whales. Effects of fetal sex, dam parity or age, and season were evaluated across either day post-conception (DPC), stage of pregnancy (PRE, EARLY, MID, LATE, POST) or indexed month post-conception (IMPC) using a mixed model linear regression with animal ID and pregnancy number as the random variables. Across DPC, DHEA, A4 and T concentrations were affected (P<0.05) by season, with highest concentrations during spring (DHEA, A4, & T) and summer (A4) as compared to the fall. A significant effect of parity on androgen production was observed only for DHEA, with multiparous females having higher (P=0.01) concentrations than nulliparous females. All three androgens significantly increased with each successive pregnancy stage and IMPC with peak concentrations occurring during IMPC 10 (DHEA), 13 (A4) and 14 (T), respectively. Cortisol was affected by season (P=0.03) with highest concentrations being detected during the months of fall, while Co was only affected by parity (P=0.003) with significant increases observed for primiparous females as compared to nulliparous females. Cortisol and Co concentrations peaked (P<0.05) during IMPC 17 (i.e., the month prior to parturition). The C to Co ratio during pregnancy was 7.4 to 1, indicating that cortisol is the major circulating glucocorticoid studied to date in pregnant killer whales. The significant increase in concentrations of maternal androgens throughout pregnancy, which were unrelated to fetal sex, indicates that they play an important role during killer whale fetal development.
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Andrógenos/sangre , Glucocorticoides/sangre , Orca/sangre , Androstenodiona/sangre , Animales , Corticosterona/sangre , Deshidroepiandrosterona/sangre , Femenino , Feto/metabolismo , Hidrocortisona/sangre , Masculino , Parto/sangre , Embarazo , Testosterona/sangreRESUMEN
The present study aimed to describe serum anti-Müllerian hormone (AMH) patterns of ex situ male and female beluga to examine the influence of age (divided into 5-year categories) or sexual maturation and reproductive season. In males aged 5-9 years, AMH concentrations were significantly (P<0.05) higher than those in all age categories exceeding 15 years and were not influenced by season (P=0.57). AMH concentrations in females peaked in the 5-9-year age category during the breeding season and decreased (P<0.05) after 9 years of age. Aged females displayed lower (P<0.05) AMH concentrations than immature and mature animals and immature females secreted higher concentrations than mature animals (P=0.03). For mature females, seasonal differences (P=0.02) in AMH concentrations were detected, with females in the breeding season displaying higher AMH concentrations than in the non-breeding season. This is the first time AMH has been characterised in a cetacean species and the first potential hormonal evidence of reproductive senescence in beluga. Further research is required to determine if this hormone can be used as a predictor of fertility for the species.
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Hormona Antimülleriana/sangre , Ballena Beluga/sangre , Reproducción/fisiología , Estaciones del Año , Factores de Edad , Animales , Femenino , Fertilidad/fisiología , MasculinoRESUMEN
The secretory patterns of progestagens and estrogens were characterized throughout 28 normal pregnancies until two month post-partum in eleven killer whales. HPLC analysis of serum from different reproductive stages (luteal phase, EARLY, MID, and LATE pregnancy) identified three major immunoreactive progestagen peaks; progesterone (P4), 5α-pregnane-3,20-dione (5α-DHP) and pregnanediol, with 5α-DHP approximately half of that for P4 in the luteal phase, and EARLY, but approximately 2/3 of P4 during MID and LATE pregnancy. At birth, 5α-DHP was the only significant (>10% immunoreactivity) immunoreactive progestagen detected in placental (umbilical cord) serum. Maternal recognition of pregnancy appears to occur between day 21 and 28 post-ovulation when a significant deviation in progestagen concentrations between conceptive and non-conceptive cycles was detected. Progestagen concentrations during pregnancy displayed a bimodal pattern with significant peaks (P<0.05) in EARLY (indexed month post-conception [IMPC] 2, 3, 4) and MID (IMPC 9, 10) before decreasing (P<0.05) over an 11day interval to luteal phase concentrations on the day of parturition. Among estrogens, estriol was secreted in the highest concentrations but only estrone (free and conjugated) and estradiol increased (P<0.001) during pregnancy, with peaks observed during the final month of gestation, and an influence (P<0.05) of fetal sex on estradiol production was detected. Collective findings indicate that P4 derived from the corpus luteum is the major biologically active progestagen during the luteal phase and pregnancy, and that 5α-DHP production, possibly from both luteal and placental sources, increases during the second half of pregnancy.
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Estrógenos/metabolismo , Progestinas/metabolismo , Animales , Estrógenos/análisis , Femenino , Embarazo , Progestinas/análisis , OrcaRESUMEN
Research was performed to increase our understanding of male Magellanic penguin (Spheniscus magellanicus) reproductive biology and to develop artificial insemination (AI) technology to assist with maintaining the species' genetic diversity. Seminal traits were characterized from seven males with noncontaminated ejaculates (n = 123) displaying high in vitro motion parameters, membrane integrity, and morphology. Seven females were maintained in nest sites that permitted visual, auditory, and tactile contact with their paired male but not copulation for 18.3 ± 2.4 days before egg lay. After cloacal AI (2.6 ± 0.4 inseminations/female) with semen chilled for up to 20.5 hr at 5°C, all females produced one to two fertile eggs, with the first oviposition occurring within 7 days of plasma progesterone concentrations exceeding 0.8 ng/ml. Overall fertility was 91.7%, hatchability was 63.6%, and genetic analyses confirmed that all embryos and hatchlings were sired by AI males. The heterospermic AI design demonstrated that eggs were fertilized by spermatozoa chilled for 1.5-19.8 hr before AI and were laid 4.5-11.5 days post AI. These results contribute new data on Magellanic penguin sperm biology and demonstrate that high fertility rates after AI of chilled semen can be achieved with females remaining in proximity to their paired mate.
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Frío , Inseminación Artificial/veterinaria , Preservación de Semen/veterinaria , Spheniscidae/fisiología , Animales , Estrógenos/sangre , Femenino , Masculino , Preservación de Semen/métodos , Espermatozoides/fisiología , Spheniscidae/sangreRESUMEN
The goal of this study was to describe profiles of serum estrogens, testosterone and cortisol during normal pregnancy in bottlenose dolphins. Predominant estrogens in all categories of dolphin sera pools during estrus and pregnancy (EARLY: Days 0-120; MID: Days 121-240; LATE: Days 241 to parturition; Day 0=day of conception) were estrone/estrone conjugates (E1-C) and estriol (E3). Serum samples collected throughout 101 normal pregnancies were analyzed for E1-C, E3, testosterone (T) and cortisol (CORT). E1-C was higher (P<0.05) during LATE compared to EARLY and MID, and higher (P<0.05) in nulliparous than multiparous females. E1-C concentrations were also inversely associated with maternal age (P=0.05). E3 was higher (P<0.05) in EARLY than MID and LATE, and higher overall for nulliparous than multiparous females, but concentrations were similar among gestational stages when parity was excluded from analyses. Analysis by indexed month post-conception (IMPC) demonstrated that E1-C increased from IMPC 9 and peaked at IMPC 11. E3 was significantly elevated during IMPC 1, decreased until IMPC 6 and peaked at IMPC 11. T increased (P<0.05) at IMPC 3 and continued to increase throughout gestation (P<0.05). CORT was higher (P<0.05) during LATE compared to EARLY and MID (P<0.05), peaked during IMPC 12, and was not affected by parity. Hormone profiles were not influenced by fetal sex.
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Estrógenos/sangre , Hidrocortisona/sangre , Preñez/sangre , Testosterona/sangre , Animales , Delfín Mular , Estro/sangre , Femenino , Masculino , Parto/fisiología , Embarazo , Progesterona/sangreRESUMEN
Franks et al. (2016) consider that the degree of error in estimated ages used to define survivorship patterns of northern and southern resident killer whale ( Orcinus orca ) populations is of insignificant impact to estimates of the species' postreproductive lifespan (PRLS). We provide evidence that survival probabilities for killer whales using a dataset comprising estimated age animals differ significantly from that determined using data collected from known-age animals in the Pacific Northwest over the past 40 years. Consequently, our findings indicate that the degree of error in age estimates and ensuing survivorship patterns do not support the notion by Franks et al. (2016) of a prolonged PRLS in the female killer whale that is comparable to the PRLS observed in humans.
RESUMEN
Data collected on life-history parameters of known-age animals from the northern (NR) and southern resident (SR) killer whales (Orcinus orca) of the eastern North Pacific were compared with life-history traits of killer whales located at SeaWorld (SEA) facilities. For captive-born SEA animals, mean age and body length at 1st estrus was 7.5 years and 483.7cm, respectively. Estimated mean age at 1st conception was different (P < 0.001) for the combined data from both northern and southern resident (NSR) free-ranging populations (12.1 years) compared to SEA (9.8 years), as was the estimated mean age at 1st observed calf (SEA: 11.1 years, NSR: 14.2 years, P < 0.001). Average calf survival rate to 2 years of age for SEA animals (0.966) was significantly greater (P = 0.04) than that for SR (0.799). Annual survival rate (ASR) for SEA increased over approximately 15-year increments with rates in the most recent period (2000-2015 ASR: 0.976) improved (P < 0.05) over the first 2 periods of captivity (1965-1985: 0.906; 1985-2000: 0.941). The SR (0.966) and NR ASR (0.977) were higher (P ≤ 0.05) than that of SEA until 2000, after which there were no inter-population differences. Based on ASR, median and average life expectancy were 28.8 and 41.6 years (SEA: 2000-2015), 20.1 and 29.0 years (SR), and 29.3 and 42.3 years (NR), respectively. The ASR for animals born at SEA (0.979) was higher (P = 0.02) than that of wild-caught SEA animals (0.944) with a median and average life expectancy of 33.1 and 47.7 years, respectively. These data present evidence for similar life-history parameters of free-ranging and captive killer whale populations and the reproductive potential and survivorship patterns established herein have application for use in future research concerning the overall health of both populations.
RESUMEN
Research was conducted to examine seasonal seminal traits and to establish short-term and long-term sperm preservation methods in the king penguin (Aptenodytes patagonicus) for use in genome banking and artificial insemination (AI). Spermic ejaculates (n = 87) obtained using a cooperative method were collected across multiple (n = 6, Male 1) and a single (Male 2) breeding season(s). Non-contaminated ejaculates (n = 69) were 0.36 ± 0.32 ml at 56.3 ± 62.7 × 10(7) sperm/ml with 85.3 ± 10.6% total motility (TMot), 52.5 ± 12.9% progressive motility (PMot), 86.6 ± 24.3 µm/sec average path velocity (VAP) and 92.3 ± 3.7% plasma membrane intact. In vitro quality of chilled semen was best maintained over 48 hr at 5°C than 21°C, with decreased (P < 0.05) motility and morphology parameters observed by 24 and 6 hr, respectively. A comparison of two freezing methods (straw [STR] vs. directional [DF]) demonstrated similar effects on post-thaw quality at 0 and 3 hr, with the exception of plasma membrane integrity which was higher (P < 0.05) at 0 hr for DF (48.7 ± 6.5%) than STR (41.2 ± 7.0%). At 0 hr post-thaw, DF samples retained 46%, 69%, and 52% of their initial PMot, VAP, and plasma membrane integrity, respectively. Normal morphology of motile cells was reduced (P < 0.05) during freeze-thawing from 84% post-collection to 37% and 34% at 0 and 3 hr post-thaw, respectively. Results indicate that chilled and cryopreserved semen from the king penguin has potential for use in AI.