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Brammer-Robbins E, Cowart JR, Calderon M, Burgess EA, Larkin IV, Martyniuk CJ. Sirenian (manatees and dugongs) reproductive endocrinology. Gen Comp Endocrinol 2024; 356:114575. [PMID: 38908455 DOI: 10.1016/j.ygcen.2024.114575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 06/19/2024] [Indexed: 06/24/2024]
Abstract
Reproductive hormones are essential to mating systems, behavior, fertility, gestation, parturition, and lactation in mammals and understanding the role of hormones in these processes is essential for species conservation. Sirenia is a unique order of marine mammals that include manatees, dugongs, and the extinct Steller's sea cow. Extant Sirenian species are all listed as vulnerable due to habitat loss, cold stress, boat strike trauma, harmful algal bloom toxicity, entanglements, and illegal hunting. Therefore, successful reproduction is essential to maintaining and increasing Sirenian populations. Understanding Sirenian reproductive behavior, endocrinology, and mating strategies will aid conservation and management efforts to protect and provide the proper conditions for successful reproduction. The objectives of this review were to synthesize the current knowledge regarding reproductive cycles and endocrinology of Sirenians and identify knowledge gaps for future investigation. The current literature on Sirenian reproductive physiology reports reproductive seasonality, sexual maturation, estrous cyclicity and acyclicity, pregnancy, and sex differences. However, there remain significant knowledge gaps on the cyclicity and pulsatile release of gonadotropins, maturation in females, and characterization of pregnancy hormone profiles throughout gestation. To date, there is no explanation for confirmed pattern for ovarian acyclicity, nor understanding of the function of the numerous accessory corpus luteum described in manatees. Research including a greater number of longitudinal and postmortem studies on a wider variety of wild manatee populations are important first steps. Taken together, understanding the reproductive endocrinology of these vulnerable and threatened species is critical for policy and management decisions to better inform protection initiatives.
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Affiliation(s)
- Elizabeth Brammer-Robbins
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA; Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, USA; Aquatic Animal Health Program, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA.
| | - Jonathan R Cowart
- Aquatic Animal Health Program, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| | - Monica Calderon
- Aquatic Animal Health Program, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| | | | - Iskande V Larkin
- Aquatic Animal Health Program, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| | - Christopher J Martyniuk
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA; Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, USA
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Brammer-Robbins E, Nouri MZ, Griffin EK, Aristizabal-Henao JJ, Denslow ND, Bowden JA, Larkin IV, Martyniuk CJ. Lipidomics and plasma hormone analysis differentiate reproductive and pregnancy statuses in Florida manatees (Trichechus manatus latirostris). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART D, GENOMICS & PROTEOMICS 2024; 50:101231. [PMID: 38643744 DOI: 10.1016/j.cbd.2024.101231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 01/26/2024] [Accepted: 03/18/2024] [Indexed: 04/23/2024]
Abstract
Florida manatees (Trichechus manatus latirostris) are protected as a threatened species, and data are lacking regarding their reproductive physiology. This study aimed to (1) quantify plasma steroid hormones in Florida manatees from two field sites, Crystal River and Indian River Lagoon, at different gestational stages and to (2) identify individual lipids associated with pregnancy status. Ultra-high performance liquid chromatography-tandem mass spectrometric analysis was used to measure plasma steroid hormones and lipids. Pregnant female manatees were morphometrically distinct from male and non-pregnant female manatees, characterized by larger body weight and maximal girth. Progesterone concentrations in manatees were also elevated during early gestation versus late gestation. Cholesterol, an important metabolic lipid, and precursor for reproductive steroids, was not different between groups. Mass spectrometry quantified 949 lipids. Plasma concentrations of glycerophospholipids, glycerolipids, sphingolipids, acylcarnitines, and cholesteryl esters were associated with pregnancy status in the Florida manatee. Most of the lipid species associated with pregnancy were triacylglycerides, phosphatidylethanolamines, and ether-linked phosphatidylethanolamines, which may serve as energy sources for fetal development. This research contributes to improving knowledge of manatee reproductive physiology by providing data on plasma steroid hormones relative to reproductive status and by identifying plasma lipids that may be important for pregnancy. Elucidation of lipid species directly associated with pregnancy has the potential to serve as a diagnostic approach to identify pregnant individuals in fresh and archived samples. These biochemical and morphometric indicators of reproductive status advance the understanding of manatee physiology.
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Affiliation(s)
- Elizabeth Brammer-Robbins
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States of America; Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, United States of America.
| | - Mohammad-Zaman Nouri
- Access Genetics & OralDNA Labs, Eden Prairie, MN 55344, United States of America
| | - Emily K Griffin
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States of America; Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, United States of America
| | | | - Nancy D Denslow
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States of America; Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, United States of America; Genetics Institute, University of Florida, Gainesville, FL, United States of America
| | - John A Bowden
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States of America; Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, United States of America; Department of Chemistry, College of Liberal Arts and Sciences, University of Florida, Gainesville, FL 32611, United States of America
| | - Iske V Larkin
- Aquatic Animal Health Program, Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida Gainesville, FL, United States of America
| | - Christopher J Martyniuk
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States of America; Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, United States of America; Genetics Institute, University of Florida, Gainesville, FL, United States of America
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Cowart JR, Collins DM, Mignucci-Giannoni AA, Alejandro-Zayas T, Rivera-Guzman AL, Larkin IV. Manual Collection and Semen Characterization in a West Indian Manatee ( Trichechus manatus). Front Vet Sci 2020; 7:569993. [PMID: 33195557 PMCID: PMC7642902 DOI: 10.3389/fvets.2020.569993] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 09/17/2020] [Indexed: 11/13/2022] Open
Abstract
Limited information is available regarding male reproductive physiology in West Indian manatees (Trichechus manatus). Currently, only basic ultrastructural and morphometric descriptions of the spermatozoon exist; however, there are no reports evaluating any seminal characteristics in this species. Therefore, the aim of the study was to fill current gaps in knowledge regarding semen parameters in West Indian manatees by collecting and characterizing multiple ejaculate samples from a single, adult West Indian manatee. Samples were analyzed for the following semen parameters: volume, agglutination, pH, osmolality, viscosity, concentration, total sperm number, motility and kinematic parameters, morphology, plasma membrane integrity, acrosome integrity, chromatin maturation, and chromatin condensation. All macroscopic semen parameters varied to some extent between samples. Total and progressive motility was high for ejaculates 2 to 5, exceeding 97 and 89%, respectively; however, these parameters decreased dramatically throughout ejaculates 6 and 7. Across all samples, curvilinear velocity, straight-line velocity, and average pathway velocity represented the largest significant differences (p < 0.001) between each of the progression velocity subgroups (rapid, medium, slow). Sperm characteristics, including acrosome integrity (79.8%), chromatin condensation (93.1%), and chromatin maturation (99.5%) were very high; however, high numbers of morphologically abnormal sperm were present (52.9%) and plasma membrane integrity was low (45.1%). These results are the first of their kind for this species and suggest high semen quality, based on multiple ejaculates, in this male West Indian manatee.
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Affiliation(s)
- Jonathan R Cowart
- Aquatic Animal Health Program, University of Florida College of Veterinary Medicine, Gainesville, FL, United States
| | - Danielle M Collins
- Department of Animal Sciences, University of Florida, Gainesville, FL, United States
| | - Antonio A Mignucci-Giannoni
- Caribbean Manatee Conservation Center, Inter American University of Puerto Rico, Bayamón, Puerto Rico.,Center for Conservation Medicine and Ecosystem Health, Ross University School of Veterinary Medicine, Basseterre, Saint Kitts and Nevis
| | - Tamara Alejandro-Zayas
- Caribbean Manatee Conservation Center, Inter American University of Puerto Rico, Bayamón, Puerto Rico
| | - Antonio L Rivera-Guzman
- Caribbean Manatee Conservation Center, Inter American University of Puerto Rico, Bayamón, Puerto Rico
| | - Iskande V Larkin
- Aquatic Animal Health Program, University of Florida College of Veterinary Medicine, Gainesville, FL, United States
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Pollock KE, O'Brien JK, Roth TL, Proudfoot J, Niederlander J, Micheas L, Robeck TR, Stoops MA. Anti-Müllerian hormone in managed African and Asian rhino species. Gen Comp Endocrinol 2020; 294:113487. [PMID: 32278883 DOI: 10.1016/j.ygcen.2020.113487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/14/2020] [Accepted: 04/04/2020] [Indexed: 11/30/2022]
Abstract
Serum collected across the lifespan of four managed rhino species: black (Diceros bicornis, n = 16), white (Ceratotherium simum simum, n = 19), greater one-horned (GOH, Rhinoceros unicornis, n = 11) and Sumatran (Dicerorhinus sumatrensis, n = 6) were validated and analyzed in an anti-Müllerian hormone (AMH) enzyme- linked immunoassay. Concentrations of AMH were examined over time, between sexes and throughout different reproductive states which included n = 3 female white rhinos immunocontracepted with porcine zona pellucida (pZP). Across species, males produced higher AMH concentrations compared to females. Among males, AMH concentrations varied by species aside from comparable values secreted between black and white rhinos. The GOH and Sumatran rhino secreted the highest and lowest male AMH concentrations, respectively. However, within each species, AMH concentrations were similar across male age categories. Preliminary insight into male AMH changes from birth to sexual maturity suggest its potential as a marker for onset of testicular maturation. Female black, GOH and Sumatran rhinos secreted comparable AMH concentrations which were higher than those in white rhino. Within each species, inter-individual variation in AMH secretion occurred among females of similar age. While AMH secretion did not differ across the ages sampled for female white (4->26 yr) and GOH (4-26 yr) rhinos, black and Sumatran rhinos >26 and <4 yr, respectively secreted lower AMH compared to conspecific females 7-26 yr of age. Two idiopathic infertility cases corresponded to low (outside species range) AMH values. The establishment of normative AMH concentrations in managed African and Asian rhinos provides an additional metric beyond traditional sex steroids to assess gonadal function. Further work is needed to determine if AMH can predict fertility potential in rhinos.
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Affiliation(s)
- K E Pollock
- Center for Conservation and Research of Endangered Wildlife, Cincinnati Zoo & Botanical Garden, 3400 Vine Street, Cincinnati, OH 45220, USA
| | - J K O'Brien
- SeaWorld and Busch Gardens Reproductive Research Center, SeaWorld Parks and Entertainment, 2595 Ingraham St, San Diego, CA 92109, USA
| | - T L Roth
- Center for Conservation and Research of Endangered Wildlife, Cincinnati Zoo & Botanical Garden, 3400 Vine Street, Cincinnati, OH 45220, USA
| | - J Proudfoot
- Indianapolis Zoo, 1200 W Washington St, Indianapolis, IN 46222, USA
| | | | - L Micheas
- University of Missouri, Columbia, MO 65211, USA
| | - T R Robeck
- SeaWorld and Busch Gardens Reproductive Research Center, SeaWorld Parks and Entertainment, 2595 Ingraham St, San Diego, CA 92109, USA
| | - M A Stoops
- Center for Conservation and Research of Endangered Wildlife, Cincinnati Zoo & Botanical Garden, 3400 Vine Street, Cincinnati, OH 45220, USA.
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Wetzel DL, Reynolds JE, Bonde RK, Schloesser RW, Schwierzke-Wade L, Roudebush WE. Enhancing reproductive assessments of the Florida manatee Trichechus manatus latirostris by establishing optimal time period and inhibin B baseline concentrations. ENDANGER SPECIES RES 2019. [DOI: 10.3354/esr00972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Place NJ, Crosier AE, Comizzoli P, Nagashima JB, Haefele H, Schmidt-Küntzel A, Marker LL. Age-associated and deslorelin-induced declines in serum anti-Müllerian hormone concentrations in female cheetahs, Acinonyx jubatus. Gen Comp Endocrinol 2017; 250:54-57. [PMID: 28602789 DOI: 10.1016/j.ygcen.2017.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/30/2017] [Accepted: 06/05/2017] [Indexed: 11/29/2022]
Abstract
Anti-Müllerian hormone (AMH) is widely used in human medicine to non-invasively estimate the size of the ovarian follicle reserve and to predict the ovarian response to gonadotropin stimulation in the context of assisted reproductive technologies (e.g., IVF). These applications of AMH testing have recently expanded to non-human mammals, with production animals, such as cows, goats and sheep being the primary focus of AMH research. However, few investigations have involved exotic species, and in particular carnivores. In this study, we measured AMH concentrations (0.078-3.078ng/mL) in archived serum samples that had been collected from 36 adult female cheetahs across their reproductive lifespan (2-15years of age). Similar to other mammals, AMH concentration in cheetahs declined with age, and its variability among females of the same age was considerable. The rates at which AMH declined over time in individual cheetahs were also highly variable. Five cheetahs had been contracepted with the long-acting GnRH agonist deslorelin for 6-18months prior to sample collection, and their AMH concentrations were relatively low compared to untreated females. In this first study of AMH in an exotic carnivore, the findings demonstrate that the age-associated decline in AMH is highly variable and that deslorelin appears to suppress AMH concentration in serum. Owing to the increased use of assisted reproductive technologies in ex situ populations of threatened and endangered species, such as cheetahs, the present study's findings will need to be taken into consideration if AMH is to be used successfully to optimize breeding management decisions in exotic species.
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Affiliation(s)
- Ned J Place
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA.
| | - Adrienne E Crosier
- Smithsonian Conservation Biology Institute, Front Royal, VA and Washington, DC, USA
| | - Pierre Comizzoli
- Smithsonian Conservation Biology Institute, Front Royal, VA and Washington, DC, USA
| | - Jennifer B Nagashima
- Smithsonian Conservation Biology Institute, Front Royal, VA and Washington, DC, USA
| | | | | | - Laurie L Marker
- Cheetah Conservation Fund, P.O. Box 1755, Otjiwarongo, Namibia
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Montano GA, Robeck TR, Steinman KJ, O'Brien JK. Circulating anti-Müllerian hormone concentrations in relation to age and season in male and female beluga (Delphinapterus leucas). Reprod Fertil Dev 2017; 29:1642-1652. [DOI: 10.1071/rd15537] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 08/07/2016] [Indexed: 12/31/2022] Open
Abstract
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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Lanyon JM, Burgess EA. Methods to examine reproductive biology in free-ranging, fully-marine mammals. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 753:241-74. [PMID: 25091913 DOI: 10.1007/978-1-4939-0820-2_11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Historical overexploitation of marine mammals, combined with present-day pressures, has resulted in severely depleted populations, with many species listed as threatened or endangered. Understanding breeding patterns of threatened marine mammals is crucial to assessing population viability, potential recovery and conservation actions. However, determining reproductive parameters of wild fully-marine mammals (cetaceans and sirenians) is challenging due to their wide distributions, high mobility, inaccessible habitats, cryptic lifestyles and in many cases, large body size and intractability. Consequently, reproductive biologists employ an innovative suite of methods to collect useful information from these species. This chapter reviews historic, recent and state-of-the-art methods to examine diverse aspects of reproduction in fully-aquatic mammals.
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Affiliation(s)
- Janet M Lanyon
- School of Biological Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia,
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Flamm RO, Reynolds JE, Harmak C. Improving conservation of Florida manatees (Trichechus manatus latirostris): conceptualization and contributions toward a regional warm-water network management strategy for sustainable winter habitat. ENVIRONMENTAL MANAGEMENT 2013; 51:154-166. [PMID: 23161252 DOI: 10.1007/s00267-012-9985-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 10/28/2012] [Indexed: 06/01/2023]
Abstract
We used southwestern Florida as a case study to lay the groundwork for an intended and organized decision-making process for managing warm-water habitat needed by endangered manatees to survive winters in Florida. Scientists and managers have prioritized (a) projecting how the network of warm-water sites will change over the next 50 years as warmed industrial discharges may expire and as flows of natural springs are reduced through redirection of water for human uses, and (b) mitigating such changes to prevent undue consequences to manatees. Given the complexities introduced by manatee ecology; agency organizational structure; shifting public demands; fluctuating resource availability; and managing within interacting cultural, social, political, and environmental contexts, it was clear that a structured decision process was needed. To help promote such a process, we collected information relevant to future decisions including maps of known and suspected warm-water sites and prototyped a characterization of sites and networks. We propose steps that would lead to models that might serve as core tools in manatee/warm-water decision-making, and we summarized topics relevant for informed decision-making (e.g., manatee spatial cognition, risk of cold-stress morbidity and mortality, and human dimensions). A major impetus behind this effort is to ensure proactively that robust modeling tools are available well in advance of the anticipated need for a critical management decision.
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Affiliation(s)
- Richard Owen Flamm
- Fish and Wildlife Research Institute, Florida Fish & Wildlife Conservation Commission, St. Petersburg, FL 33701, USA.
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Roudebush WE, Nethery RA, Heldreth T. Presence of anti-müllerian hormone in the squirrel monkey (Saimiri boliviensis
): gender and seasonal differences. J Med Primatol 2012; 42:15-9. [DOI: 10.1111/jmp.12022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2012] [Indexed: 11/30/2022]
Affiliation(s)
- William E. Roudebush
- Department of Biomedical Sciences; University of South Carolina School of Medicine-Greenville; Greenville SC USA
| | - R. Andrew Nethery
- Department of Biology; Charleston Southern University; Charleston SC USA
| | - Todd Heldreth
- Department of Biology; Charleston Southern University; Charleston SC USA
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