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Otero Y, Calatayud NE, Arcia ID, Mariscal D, Samaniego D, Rodríguez D, Rodríguez K, Guerrel J, Ibáñez R, Della Togna G. Recovery and Characterization of Spermatozoa in a Neotropical, Terrestrial, Direct-Developing Riparian Frog ( Craugastor evanesco) through Hormonal Stimulation. Animals (Basel) 2023; 13:2689. [PMID: 37684953 PMCID: PMC10486684 DOI: 10.3390/ani13172689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/19/2023] [Accepted: 08/19/2023] [Indexed: 09/10/2023] Open
Abstract
The Vanishing Rainfrog (Craugastor evanesco) is an endemic and critically endangered frog species of Panama. It is suspected that 90% of the population has disappeared from the wild. Frogs were collected from the wild and brought to a Captive Breeding Program; however, accomplishing regular reproductive events for this species has been difficult. The objective of this study was to determine the effect of hormonal stimulation on the production and quality of C. evanesco spermatozoa, aiming to develop an efficient and safe sperm collection protocol as a tool to help reproduce this endangered species. Mature males received intra-peritoneal injections with one of six hormone treatments, including des-Gly10, D-Ala6, Pro-NHEt9-GnRH-A, Amphiplex or hCG. Urine samples were collected at 10 different time points post-injection. Quality assessments included sperm concentration, percentage motility, percentage forward progressive motility (FPM), osmolality, pH and morphology analysis. Our results indicate that the optimal treatment for the collection of highly concentrated sperm samples of C. evanesco is 4 µg/gbw GnRH, followed by Amphiplex and 2 µg/gbw GnRH as sub-optimal treatments and finally, 6 µg/gbw GnRH and 5 and 10 IU/gbw hCG as non-optimal treatments. GnRH-A at 4 μg/gbw and Amphiplex stimulated the production of samples with the highest sperm concentrations and quality, despite Amphiplex producing lower percentages of intact acrosome and tail. In contrast, hCG concentrations were not reliable inducers of sperm production, consistently showing lower concentrations, higher percentages of sperm abnormalities and more acidic spermic urine than that induced by Amphiplex and GnRH-A. Morphological assessments revealed that C. evanesco spermatozoa have a filiform shape with a large acrosome on the anterior part of an elongated head, a small midpiece and a long tail with two filaments joined together by an undulating membrane.
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Affiliation(s)
- Yineska Otero
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Medicina Veterinaria, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Natalie E. Calatayud
- San Diego Zoo Wildlife Alliance, Beckman Center for Conservation Research, 15600 San Pasqual Valley Road, Escondido, CA 92025, USA;
| | - Igli D. Arcia
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
| | - Denise Mariscal
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Medicina Veterinaria, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Diego Samaniego
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Medicina Veterinaria, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Dionel Rodríguez
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Ciencias Naturales, Exactas y Tecnología, Escuela de Biología, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Karina Rodríguez
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Ciencias Naturales, Exactas y Tecnología, Escuela de Biología, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Jorge Guerrel
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
| | - Roberto Ibáñez
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Ciencias Naturales, Exactas y Tecnología, Escuela de Biología, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Gina Della Togna
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- The Amphibian Survival Alliance, Apartado 0830-00689, Panama
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Prado NA, Carlstead K, Malloy EJ, Paris S, Wielebnowski N, Rockwood LL, Brown JL. Ovarian cyclicity and prolactin status of African elephants (Loxodonta africana) in North American zoos may be influenced by life experience and individual temperament. Horm Behav 2020; 125:104804. [PMID: 32531397 DOI: 10.1016/j.yhbeh.2020.104804] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/21/2020] [Accepted: 06/05/2020] [Indexed: 11/23/2022]
Abstract
Hyperprolactinemia is an endocrine disorder associated with infertility in many species, including elephants. In a recent survey of zoos accredited by the Association of Zoos and Aquariums (AZA), over half of African elephant females (N = 101) were not cycling normally, 30% of which exhibited hyperprolactinemia. We examined whether life experience and temperament predict ovarian cyclicity and circulating prolactin status in individual African elephant females. We hypothesized that, similar to humans, acyclicity and hyperprolactinemia in elephants will be associated with an apprehensive or fearful, anxious temperament, and an increased number of potentially challenging life events (transfers, deaths and births). Ninety-five adult African elephant females housed at 37 AZA institutions were included in this study. Blood samples were collected twice a month for 1 year to determine ovarian cycle (cycling, n = 44; irregular, n = 13; non-cycling, n = 38) and prolactin (normal, n = 44; low; n = 23; high; n = 28) status. Keeper ratings on a 6-point scale were obtained on 32 temperament traits in 85 of these elephants. We determined that giving birth and being exposed to herd mates entering the facility were positively associated with normal ovarian cycle and prolactin profiles. By contrast, age, serum cortisol, and an increased number of herd mates leaving a facility were negatively associated with both. Contrary to our hypothesis, hyperprolactinemia was associated with a popular and caring temperament rating, whereas consistently low prolactin was associated with a fearful, apprehensive temperament. These findings indicate that pituitary-ovarian function may be impacted by life history (cyclicity) and temperament (prolactin), which should be taken into consideration when making management decisions.
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Affiliation(s)
- Natalia A Prado
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, VA, USA.
| | - Kathy Carlstead
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, VA, USA
| | - Elizabeth J Malloy
- Department of Mathematics and Statistics, American University, 4400 Massachusetts Ave. NW, Washington, DC, USA
| | - Stephen Paris
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, VA, USA
| | | | - Larry L Rockwood
- Department of Biology, George Mason University, Fairfax, VA, USA
| | - Janine L Brown
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, VA, USA
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Della Togna G, Howell LG, Clulow J, Langhorne CJ, Marcec-Greaves R, Calatayud NE. Evaluating amphibian biobanking and reproduction for captive breeding programs according to the Amphibian Conservation Action Plan objectives. Theriogenology 2020; 150:412-431. [PMID: 32127175 DOI: 10.1016/j.theriogenology.2020.02.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 02/16/2020] [Indexed: 01/18/2023]
Abstract
The Amphibian Conservation Action Plan (ACAP), published in 2007, is a formal document of international significance that proposed eleven relevant actions for global amphibian conservation. Action seven of the ACAP document addresses the use of amphibian captive programs as a conservation tool. Appendix material under this action explores the potential use of Genome Resource Banking (biobanking) as an urgently needed tool for these captive programs. ACAP proposed twelve objectives for Genome Resource Banking which exhibit little emphasis on reproduction as a vital underlying science for amphibian Captive Breeding Programs (CBP's). Here we have reassessed the original twelve ACAP objectives for amphibian reproduction and biobanking for CBP's as a contribution to future ACAP review processes. We have reviewed recent advances since the original objectives, as well as highlighted weaknesses and strengths for each of these objectives. We make various scientific, policy and economic recommendations based on the current reality and recent advances in relevant science in order to inform future ACAP towards new global objectives. The number of amphibian CBP'S has escalated in recent years and reproductive success is not always easily accomplished. Increases in applied and fundamental research on the natural history and reproductive biology of these species, followed by the appropriate development and application of artificial reproductive technologies (ART's) and the incorporation of genome resource banks (GRB's), may turn CBP's into a more powerful tool for amphibian conservation.
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Affiliation(s)
- Gina Della Togna
- Universidad Interamericana de Panama, Dirección de Investigación, Campus Central, Avenida Ricardo J. Alfaro, Panama; Smithsonian Tropical Research Institute, Panama Amphibian Rescue and Conservation Project, Panama.
| | - Lachlan G Howell
- University of Newcastle, Conservation Biology Research Group, University Drive, Callaghan, NSW, 2308, Australia
| | - John Clulow
- University of Newcastle, Conservation Biology Research Group, University Drive, Callaghan, NSW, 2308, Australia
| | | | - Ruth Marcec-Greaves
- National Amphibian Conservation Center, Detroit Zoological Society, Royal Oak, MI, 48067, USA
| | - Natalie E Calatayud
- San Diego Zoo Institute for Conservation Research, San Pasqual Valley Road, Escondido, CA, 92027, USA; Taronga Institute of Science and Learning, Taronga Conservation Society Australia, Taronga Western Plains Zoo, Dubbo, NSW, 2830, Australia
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Prado NA, Paris SW, Brown JL. Prolonged ovarian acyclicity is associated with a higher likelihood of developing hyperprolactinemia in zoo female African elephants. Zoo Biol 2018; 38:180-188. [DOI: 10.1002/zoo.21464] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 10/22/2018] [Accepted: 11/13/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Natalia A. Prado
- Department of Reproductive Sciences, Center for Species SurvivalSmithsonian Conservation Biology InstituteFront RoyalVirginia
| | - Stephen W. Paris
- Department of Reproductive Sciences, Center for Species SurvivalSmithsonian Conservation Biology InstituteFront RoyalVirginia
| | - Janine L. Brown
- Department of Reproductive Sciences, Center for Species SurvivalSmithsonian Conservation Biology InstituteFront RoyalVirginia
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Morfeld KA, Brown JL. Ovarian acyclicity in zoo African elephants (Loxodonta africana) is associated with high body condition scores and elevated serum insulin and leptin. Reprod Fertil Dev 2017; 28:640-7. [PMID: 25375263 DOI: 10.1071/rd14140] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 09/03/2014] [Indexed: 12/25/2022] Open
Abstract
The purpose of the present study was to determine whether excessive body fat and altered metabolic hormone concentrations in the circulation were associated with ovarian acyclicity in the world's largest land mammal, the African elephant. We compared body condition, glucose, insulin and leptin concentrations and the glucose-to-insulin ratio (G:I) between cycling (n=23; normal 14-16 week cycles based on serum progestagens for at least 2 years) and non-cycling (n=23; consistent baseline progestagen concentrations for at least 2 years) females. A validated body condition score (BCS) index (five-point scale; 1=thinnest, 5=fattest) was used to assess the degree of fatness of the study elephants. The mean BCS of non-cycling elephants was higher than that of their cycling counterparts. There were differences in concentrations of serum metabolic biomarkers, with non-cycling elephants in the BCS 5 category having higher leptin and insulin concentrations and a lower G:I ratio than cycling BCS 5 females. Using 'non-cycling' as the outcome variable in regression models, high BCS was a strong predictor of a non-cycling status. This study provides the first evidence that ovarian acyclicity in zoo African elephants is associated with body condition indicative of obesity, as well as elevated, perturbed biomarkers of metabolic status.
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Affiliation(s)
- Kari A Morfeld
- Center for Species Survival, Smithsonian Conservation Biology Institute, National Zoological Park, 1500 Remount Road, Front Royal, VA 22630, USA
| | - Janine L Brown
- Center for Species Survival, Smithsonian Conservation Biology Institute, National Zoological Park, 1500 Remount Road, Front Royal, VA 22630, USA
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Della Togna G, Trudeau VL, Gratwicke B, Evans M, Augustine L, Chia H, Bronikowski EJ, Murphy JB, Comizzoli P. Effects of hormonal stimulation on the concentration and quality of excreted spermatozoa in the critically endangered Panamanian golden frog (Atelopus zeteki). Theriogenology 2017; 91:27-35. [DOI: 10.1016/j.theriogenology.2016.12.033] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 12/26/2016] [Accepted: 12/26/2016] [Indexed: 11/29/2022]
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Brown JL, Paris S, Prado-Oviedo NA, Meehan CL, Hogan JN, Morfeld KA, Carlstead K. Reproductive Health Assessment of Female Elephants in North American Zoos and Association of Husbandry Practices with Reproductive Dysfunction in African Elephants (Loxodonta africana). PLoS One 2016; 11:e0145673. [PMID: 27416141 PMCID: PMC4945061 DOI: 10.1371/journal.pone.0145673] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 12/06/2015] [Indexed: 11/18/2022] Open
Abstract
As part of a multi-institutional study of zoo elephant welfare, we evaluated female elephants managed by zoos accredited by the Association of Zoos and Aquariums and applied epidemiological methods to determine what factors in the zoo environment are associated with reproductive problems, including ovarian acyclicity and hyperprolactinemia. Bi-weekly blood samples were collected from 95 African (Loxodonta africana) and 75 Asian (Elephas maximus) (8-55 years of age) elephants over a 12-month period for analysis of serum progestogens and prolactin. Females were categorized as normal cycling (regular 13- to 17-week cycles), irregular cycling (cycles longer or shorter than normal) or acyclic (baseline progestogens, <0.1 ng/ml throughout), and having Low/Normal (<14 or 18 ng/ml) or High (≥14 or 18 ng/ml) prolactin for Asian and African elephants, respectively. Rates of normal cycling, acyclicity and irregular cycling were 73.2, 22.5 and 4.2% for Asian, and 48.4, 37.9 and 13.7% for African elephants, respectively, all of which differed between species (P < 0.05). For African elephants, univariate assessment found that social isolation decreased and higher enrichment diversity increased the chance a female would cycle normally. The strongest multi-variable models included Age (positive) and Enrichment Diversity (negative) as important factors of acyclicity among African elephants. The Asian elephant data set was not robust enough to support multi-variable analyses of cyclicity status. Additionally, only 3% of Asian elephants were found to be hyperprolactinemic as compared to 28% of Africans, so predictive analyses of prolactin status were conducted on African elephants only. The strongest multi-variable model included Age (positive), Enrichment Diversity (negative), Alternate Feeding Methods (negative) and Social Group Contact (positive) as predictors of hyperprolactinemia. In summary, the incidence of ovarian cycle problems and hyperprolactinemia predominantly affects African elephants, and increases in social stability and feeding and enrichment diversity may have positive influences on hormone status.
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Affiliation(s)
- Janine L. Brown
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, Virginia, United States of America
| | - Stephen Paris
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, Virginia, United States of America
| | - Natalia A. Prado-Oviedo
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, Virginia, United States of America
| | | | | | - Kari A. Morfeld
- Center for Species Survival, Smithsonian Conservation Biology Institute, Front Royal, Virginia, United States of America
- Lincoln Children’s Zoo, Lincoln, Nebraska, United States of America
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Somgird C, Homkong P, Sripiboon S, Brown JL, Stout TA, Colenbrander B, Mahasawangkul S, Thitaram C. Potential of a gonadotropin-releasing hormone vaccine to suppress musth in captive male Asian elephants (Elephas maximus). Anim Reprod Sci 2016; 164:111-20. [DOI: 10.1016/j.anireprosci.2015.11.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 11/13/2015] [Accepted: 11/17/2015] [Indexed: 10/22/2022]
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Somgird C, Sripiboon S, Mahasawangkul S, Boonprasert K, Brown JL, Stout TAE, Colenbrander B, Thitaram C. Differential testosterone response to GnRH-induced LH release before and after musth in adult Asian elephant (Elephas maximus) bulls. Theriogenology 2015; 85:1225-32. [PMID: 26774889 DOI: 10.1016/j.theriogenology.2015.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Revised: 12/06/2015] [Accepted: 12/07/2015] [Indexed: 11/30/2022]
Abstract
Bull elephants exhibit marked increases in testosterone secretion during musth, and studies have shown a heightened sensitivity of the testis to GnRH-stimulated testosterone production in musth compared to nonmusth males. However, activity of the hypothalamo-pituitary-gonadal axis before or soon after musth has not been studied in detail. The aim of this study was to evaluate LH and testosterone responses to GnRH challenge in nine adult Asian elephant (Elephas maximus) bulls during three periods relative to musth: premusth, postmusth, and nonmusth. Bulls were administered 80 μg of a GnRH agonist, and blood was collected before and after injection to monitor serum hormone concentrations. The same bulls were injected with saline 2 weeks before each GnRH challenge and monitored using the same blood collection protocol. All bulls responded to GnRH, but not saline, with an increase in LH and testosterone during all three periods. The mean peak LH (1.76 ± 0.19 ng/mL; P < 0.001) and testosterone (6.71 ± 1.62 ng/mL; P = 0.019) concentrations after GnRH were higher than the respective baselines (0.57 ± 0.07 ng/mL, 3.05 ± 0.60 ng/mL). Although basal- and GnRH-induced LH secretion were similar across the stages, evaluation of the area under the curve in GnRH-treated bulls indicated that the testosterone response was greatest during premusth (2.84 ± 0.76 area units; P = 0.019) compared to postmusth (2.02 ± 0.63 area units), and nonmusth (2.01 ± 0.46 area units). This confirms earlier reports that GnRH stimulates LH release and subsequent testosterone production in bull elephants. Furthermore, although the hypothalamo-pituitary-gonadal axis is active throughout the year, the testis appears to be more responsive to LH in terms of testosterone production in the period leading up to musth, compared to the nonmusth and postmusth periods. This heightened sensitivity, perhaps as a result of LH receptor up-regulation, may prime the testis for maximal testosterone production, leading to the physiological and behavioral changes associated with musth.
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Affiliation(s)
- Chaleamchat Somgird
- Department of Companion Animal and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Elephant Research and Education, Chiang Mai University, Chiang Mai, Thailand.
| | - Supaphen Sripiboon
- Center of Excellence in Elephant Research and Education, Chiang Mai University, Chiang Mai, Thailand
| | - Sittidet Mahasawangkul
- Thai Elephant Conservation Center, National Elephant Institute, Forest Industry Organization, Lampang, Thailand
| | - Khajohnpat Boonprasert
- Thai Elephant Conservation Center, National Elephant Institute, Forest Industry Organization, Lampang, Thailand
| | - Janine L Brown
- Smithsonian Conservation Biology Institute, Smithsonian Institution, Front Royal, Virginia, USA
| | - Tom A E Stout
- Faculty of Veterinary Medicine, Utrecht University, CM, Utrecht, The Netherlands; Faculty of Veterinary Sciences, University of Pretoria, South Africa
| | - Ben Colenbrander
- Faculty of Veterinary Medicine, Utrecht University, CM, Utrecht, The Netherlands
| | - Chatchote Thitaram
- Department of Companion Animal and Wildlife Clinics, Faculty of Veterinary Medicine, Chiang Mai University, Chiang Mai, Thailand; Center of Excellence in Elephant Research and Education, Chiang Mai University, Chiang Mai, Thailand.
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Ziomkiewicz A, Wichary S, Gomula A, Pawlowski B. Trait anxiety moderates the association between estradiol and dominance in women. Physiol Behav 2015; 143:97-103. [DOI: 10.1016/j.physbeh.2015.02.045] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 02/16/2015] [Accepted: 02/24/2015] [Indexed: 12/13/2022]
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Prado-Oviedo NA, Malloy EJ, Deng X, Brown JL. Hyperprolactinemia is not associated with hyperestrogenism in noncycling African elephants (Loxodonta africana). Gen Comp Endocrinol 2013; 189:7-14. [PMID: 23623777 DOI: 10.1016/j.ygcen.2013.03.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 03/27/2013] [Accepted: 03/29/2013] [Indexed: 11/30/2022]
Abstract
African elephants in US zoos are not reproducing at replacement levels. This is in part due to physiological problems, one of which is abnormal ovarian cyclicity that has been linked to increased prolactin secretion (hyperprolactinemia). A relationship between increased estrogen production (hyperestrogenism) and hyperprolactinemia has been found in other species. Therefore, the objective of this study was to determine if elevated prolactin was associated with increased estrogen concentrations in non-cycling African elephants. In cycling elephants (n=12), prolactin secretion followed a normal cyclic pattern, with higher concentrations observed during the follicular phase; overall mean concentration was ∼18ng/ml and baseline prolactin was ∼6ng/ml. Non-cycling females (n=18) were categorized into three groups: (1) low prolactin (<15ng/ml; n=3); (2) moderate hyperprolactinemia (16-30ng/ml; n=7); and marked hyperprolactinemia (>31ng/ml; n=8). Mean urinary estrogen conjugate concentrations ranged from 5.4 to 41.4ng/mg Crt, and were similar between normal cycling (15.4±1.5ng/mg Crt) and non-cycling, low prolactin elephants (18.4±7.3ng/mg Crt), but were lower in moderate (9.4±1.3ng/mg Crt) and marked hyperprolactinemic (9.8±1.1ng/mg Crt) groups (P<0.05). In conclusion, African elephants appear to be sensitive to alterations in prolactin production, with both low (e.g., a non-cycling pattern) and high prolactin secretion being associated with abnormal ovarian activity. However, hyperestrogenism was not related to hyperprolactinemia in the non-cycling females.
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Affiliation(s)
- Natalia A Prado-Oviedo
- Department of Environmental Science and Public Policy, George Mason University, 4400 University Drive, Fairfax, VA 22030, USA.
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HILDEBRANDT TB, LUEDERS I, HERMES R, GOERITZ F, SARAGUSTY J. Anatomical, Physiological, Behavioral and Pathological Aspects of the Estrous Cycle in Elephants. ACTA ACUST UNITED AC 2012. [DOI: 10.5686/jjzwm.17.97] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Thomas B HILDEBRANDT
- Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research
| | - Imke LUEDERS
- Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research
| | - Robert HERMES
- Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research
| | - Frank GOERITZ
- Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research
| | - Joseph SARAGUSTY
- Department of Reproduction Management, Leibniz Institute for Zoo and Wildlife Research
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