Understanding Reproductive Aging in Wildlife to Improve Animal Conservation and Human Reproductive Health

Published on May 19, 2021in Frontiers in Cell and Developmental Biology5.201
· DOI :10.3389/FCELL.2021.680471
Pierre Comizzoli22
Estimated H-index: 22
(SCBI: Smithsonian Conservation Biology Institute),
Mary Ann Ottinger47
Estimated H-index: 47
(UH: University of Houston)
Similar to humans and laboratory animals, reproductive aging is observed in wild species - from small invertebrates to large mammals. Aging issues are also prevalent in rare and endangered species under human care as their life expectancy is longer than in the wild. The objectives of this review are to (1) present conserved as well as distinctive traits of reproductive aging in different wild animal species (2) highlight the value of comparative studies to address aging issues in conservation breeding as well as in human reproductive medicine, and (3) suggest next steps forward in research. From social insects to mega-vertebrates, reproductive aging studies, or observations in the wild and in breeding centers are often at the physiological or organismal scale (senescence) rather than at the germ cell level. Overall, multiple traits are conserved across very different species (depletion of the ovarian reserve or no decline in testicular functions), but unique features also exist (endless reproductive life or unaltered quality of germ cells). There is a broad consensus about the need to fill research gaps because many cellular and molecular processes observed during reproductive aging remain unknown. More research in male aging is also needed across all species. Furthermore, studies on reproductive aging of target species in their natural habitat (sentinel species) are crucial to define more accurate reproductive indicators relevant to other species, including humans, sharing the same habitats. Wild species can significantly contribute to our general knowledge of a crucial phenomenon and provide new approaches to extend reproductive lifespan.
The binturong is a medium size carnivore belonging to the Viverrid family that lives in dense forests of South-East Asia. In addition to the protection of this vulnerable species in its natural habitat (in situ), conservation breeding efforts (ex situ) aim at maintaining a good genetic diversity while increasing the number of individuals to reinforce wild populations. Both approaches require a solid understanding of binturong's basic biology. However, there is still a lack of precise information...
1 CitationsSource
#1Tuyen Kim Cat VoH-Index: 1
#2Yuka TanakaH-Index: 1
Last. Kazuhiro KawamuraH-Index: 1
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Advanced maternal age is associated with the natural oocyte depletion, leading to low oocyte yield, high infertility treatment cancellation rates, and eventual decreases in pregnancy rates. Various innovative interventions have been introduced to improve the outcome of infertility treatment for aging patients. Numerous published data demonstrated that early follicle development was regulated by intraovarian growth factors through autocrine or paracrine mechanisms. Platelet-rich plasma (PRP), a p...
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#1Cristina Quesada-Candela (University of Pittsburgh)H-Index: 2
#2Julia Loose (University of Pittsburgh)H-Index: 3
Last. Judith L. Yanowitz (University of Pittsburgh)H-Index: 12
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Purpose Reproductive decline due to parental age has become a major barrier to fertility as couples have delayed having offspring into their thirties and forties. Advanced parental age is also associated with increased incidence of neurological and cardiovascular disease in offspring. Thus, elucidating the etiology of reproductive decline is of clinical importance. Methods Deciphering the underlying processes that drive reproductive decline is particularly challenging in women in whom a discrete...
#1Ned J. Place (Cornell University)H-Index: 15
#2Alexandra M Prado (Cornell University)H-Index: 1
Last. Melissa M. Holmes (U of T: University of Toronto)H-Index: 23
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The naked mole-rat (NMR, Heterocephalus glaber) is renowned for its eusociality and exceptionally long lifespan (> 30 y) relative to its small body size (35-40 g). A NMR phenomenon that has received far less attention is that females show no decline in fertility or fecundity into their third decade of life. The age of onset of reproductive decline in many mammalian species is closely associated with the number of germ cells remaining at the age of sexual maturity. We quantified ovarian reserve s...
#1Cristian PirasH-Index: 18
#2Viviana Greco (UCSC: Catholic University of the Sacred Heart)H-Index: 11
Last. Paola RoncadaH-Index: 26
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The environment, including animals and animal products, is colonized by bacterial species that are typical and specific of every different ecological niche. Natural and human-related ecological pressure promotes the selection and expression of genes related to antimicrobial resistance (AMR). These genes might be present in a bacterial consortium but might not necessarily be expressed. Their expression could be induced by the presence of antimicrobial compounds that could originate from a given e...
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#1Adrienne E. CrosierH-Index: 17
#2Julie LamyH-Index: 1
Last. Pierre ComizzoliH-Index: 22
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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 pro...
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#1Pierre Comizzoli (SCBI: Smithsonian Conservation Biology Institute)H-Index: 22
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#1Nadine Adrianna Sugianto (University of Oxford)H-Index: 4
#2C. Newman (University of Oxford)H-Index: 4
Last. Christina D. Buesching (University of Oxford)H-Index: 26
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Abstract Among the Carnivora, there is sparse evidence for any substantive fitness benefits of post reproductive lifespan (PRLS, survival after reproductive cessation, RC). Using the European badger (Meles meles) as a model species, we analyzed sex-specific cross-sectional endocrinological and morphological data to investigate: 1) age-dependent reproductive decline in sex-steroid levels versus prime reproductive age; 2) age-dependent declines in somatic condition and reproductive advertisement (...
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#1Irem Sepil (University of Oxford)H-Index: 15
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Declining ejaculate performance with male age is taxonomically widespread and has broad fitness consequences. Ejaculate success requires fully functional germline (sperm) and soma (seminal fluid) components. However, some aging theories predict that resources should be preferentially diverted to the germline at the expense of the soma, suggesting differential impacts of aging on sperm and seminal fluid and trade-offs between them or, more broadly, between reproduction and lifespan. While harmful...
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#1Emily R. A. Cramer (SCBI: Smithsonian Conservation Biology Institute)H-Index: 12
#1Emily R. A. Cramer (SCBI: Smithsonian Conservation Biology Institute)H-Index: 1
Last. Pierre Comizzoli (SCBI: Smithsonian Conservation Biology Institute)H-Index: 22
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Extra-pair paternity may drive selection on spermatozoa and ejaculate characteristics through sperm competition and cryptic female choice. Here, we examine sperm morphology in the black-throated blue warbler (Setophaga caerulescens), an ecological model species where extra-pair paternity is frequent and is linked with male age. We test whether sperm morphology relates to several aspects of male phenotype known or suspected to affect extra-pair paternity success. Sperm morphology did not correlat...
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