Zoo Biology最新文献

{"title":"Facing Truths About Population Management.","authors":"Marcus Clauss, Andrew J Abraham, Jörg Beckmann, Mads F Bertelsen, Laurie Bingaman Lackey, Anita Burkevica, Miguel Casares, Severin Dressen, Adam Eyres, Karin Federer, Richard Gibson, Sven Hammer, Therese Hard, Stefan Hoby, Felix V Husemann, Jacques Kaandorp, Christine M Kaandorp-Huber, Bjarne Klausen, Tobias Knauf-Witzens, José Kok, Maya S Kummrow, Sébastien Laurent, Arne Lawrenz, Sabrina Linn, Imke Lueders, Pascal Marty, Dennis W H Müller, Baptiste Mulot, Rolf-Arne Ølberg, Theo B Pagel, Zjef Pereboom, Jan Pluháček, Emile F Prins, Sandra Reichler-Danielowski, Douglas Richardson, Marco Roller, Lara Scherer, Tim F Schikora, Chrispijn M Schilp, Mark Snowball, Julia Stagegaard, Hanspeter W Steinmetz, Job B G Stumpel, Cyriel Ververs, Chris Walzer, Christian Wenker, Guido Westhoff, Brian Zimmerman, João Pedro Meireles","doi":"10.1002/zoo.70099","DOIUrl":"10.1002/zoo.70099","url":null,"abstract":"<p><p>Even without considering genetic diversity, managing zoo populations sustainably without applying controlled mortality faces a predictable dilemma: Holding space is limited, and zoos worth their salt will inevitably become better at reducing accidental (uncontrolled) mortality. For most species, longevity attainable under good husbandry conditions is considerably longer than generation time, and even though most animals can reproduce until death, there is reproductive senescence, where the probability of successful reproduction decreases with age. Thus, over time, available holding space will inevitably be filled by older animals of lower fecundity. Breeding recommendations that aim at exact numerical replacement to avoid surplus at all cost rather than accounting for average success rates (so that the number of offspring will overshoot the target by up to 50% of the time) will stochastically lead to declines in population size. For small populations, extinction in zoos thus predictably becomes a matter of time. Only large populations will be able to exist at high proportions of old animals, with waves of replacement cycles. Therefore, gaining public acceptance for respectful and humane controlled mortality is essential for the long-term sustainability of small zoo populations. Concepts of continuously increasing holding capacities, using frozen gametes to generate offspring when needed, or nonspecific hopes that compassionate conservation will align individual longevity and conservation goals, detract from the necessity to act. Details of welfare and education can support the call for controlled mortality, but it is the inevitability of the outlined process that obliges us to choose honestly between being empathetic observers of extinction or taking responsibility to conserve animal species.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148798550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Navigating Welfare Contradictions in Zoo-Supported Conservation Activities.","authors":"Heather Browning, David M Powell","doi":"10.1002/zoo.70100","DOIUrl":"https://doi.org/10.1002/zoo.70100","url":null,"abstract":"<p><p>Modern zoos and aquariums focus on providing the best possible welfare for animals in their care. At the same time, they support or participate in field conservation activities, which aim to protect animal populations in the wild or reintroduce animals from human care to wild habitats. However, life for animals in the wild is potentially more difficult and exposes animals to a range of additional welfare risks, possibly resulting in lower welfare. Thus, a contradiction exists between what zoos aim for in terms of welfare for their animals and what they promote or accept for free-ranging animals. This brief commentary explores this contradiction, why it exists, and what ethical arguments may be considered in reconciling it. We recommend that zoos explicitly recognise this issue and clearly articulate their thinking about animal welfare in decisions regarding conservation activities.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":""},"PeriodicalIF":1.5,"publicationDate":"2026-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148798548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Comparison of Milk Macronutrient Composition From Domestic and Exotic Species Classified in the Order Perissodactyla.","authors":"Jenna C P Wagner, Benjamin Po, Mark S Edwards, Michael L Power, Shweta Trivedi, Larry J Minter, Kimberly Ange-van Heugten","doi":"10.1002/zoo.70054","DOIUrl":"10.1002/zoo.70054","url":null,"abstract":"<p><p>Archived and donated perissodactyla milk samples (n = 209) from 8 domestic horses (Equus caballus), 13 rhinoceroses (representing three species: Diceros bicornis, Ceratotherium simum, Rhinoceros unicornis), 5 tapirs (representing two species: Tapirus bairdii, Tapirus indicus), and 16 wild equids (representing 6 species: Equus ferus przewalskii, Equus grevyi, Equus quagga, Equus zebra, Equus africanus somaliensis, Equus asinus) were collected from different institutions (n = 16). These milk samples ranged from 3 to 200 days post parturition. Milk samples were analyzed at the Smithsonian's National Zoo and Conservation Biology Institute Nutrition Laboratory for major macronutrients: ash, crude protein (CP), dry matter (DM), crude fat, sugar, and gross energy (GE). Analysis of variance (ANOVA) and Tukey post hoc tests were used to compare milk values among both Perissodactyla species and families (Equidae, Rhinocerotidae, and Tapiridae). Overall, there was little variation of milk macronutrient compositions within perissodactyla families besides the differences between black and white rhinos observed (black rhinoceros: CP = 2.81%, fat = 2.10%, sugar = 6.06%, ash = 0.36%, DM = 11.73%, GE = 0.59 kcal/g, white rhinoceros: CP = 1.16%, fat = 0.42%, sugar = 6.47%, ash = 0.23%, DM = 8.96%, GE = 0.36 kcal/g); however, there were significant differences when comparing among families. Large differences (p < 0.05) in the CP content between Tapiridae and Equidae milk were observed (tapir: CP = 5.93%, fat = 2.57%, sugar = 4.62%, ash = 0.68%, DM = 15.09%, GE = 0.75 kcal/g, domestic horse: CP = 2.25%, fat = 1.22%, sugar = 6.35%, ash = 0.38%, DM = 11.04%, GE = 0.50 kcal/g). These findings indicate that domestic equine milk is an insufficient substitute for tapirs, but could be used for rhinoceroses. This result is likely to have a high impact on emerging Perissodactyla breeding and conservation programs with a strong need for milk formulas and replacements.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":"382-390"},"PeriodicalIF":1.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13446449/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147575433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diving Into Diversity: Considering Intra-Specific Variation in Water Immersion Activity of Aquarium-Housed Magellanic Penguins.","authors":"Takashi Yamamoto, Daiki Adachi, Tomohiro Kakizaki, Yukari Takashima, Hiroe Tsunesumi, Ken Yoda","doi":"10.1002/zoo.70072","DOIUrl":"10.1002/zoo.70072","url":null,"abstract":"<p><p>Behavioral monitoring is essential for evaluating species-appropriate functioning, with growing recognition of the importance of understanding individual-level variation in modern zoos and aquariums. Yet animals housed in large groups, such as penguins, are seldom assessed at the individual level because of the practical difficulty of observing multiple individuals simultaneously. Using animal-borne immersion loggers, we quantified long-term (mean 233 days) and high-frequency (10-min intervals across 24 h) water-use patterns in 23 Magellanic penguins Spheniscus magellanicus housed at Sumida Aquarium, Tokyo, Japan from October 2022 to October 2023, comprising 13 males and 10 females, with 11 aquarium-born and 12 wild-born individuals. Penguins exhibited predominantly diurnal immersion, although some individuals regularly showed nocturnal immersion to a lesser extent, suggesting inter-individual variation in activity chronotypes. Monthly fluctuations were modest but partly aligned with phenological periods. Individual variation was substantial: although the group-level mean immersion was 35.2%, individual values ranged widely from 20.4% to 70.1%. Immersion behavior did not differ significantly by sex or birth origin; however, aquarium-born individuals showed lower immersion on weekends than on weekdays, indicating that individual characteristics can mediate responses to external stimuli. Furthermore, immersion activity was not associated with whether an individual ever developed bumblefoot, although wild-born individuals tended to show lower susceptibility to the condition. Meanwhile, higher baseline immersion was associated with fewer diagnostic episodes in penguins with bumblefoot, reinforcing that water use likely mitigates foot problems. Overall, this study underscores the importance of considering individual variation in welfare assessments and demonstrates the utility of animal-borne tags for continuous behavioral monitoring.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":"444-458"},"PeriodicalIF":1.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13446444/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147783275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Are Visual Stimuli Enriching for Three Species of Odontocetes in Managed Care?","authors":"Deirdre Yeater, Syed Nafis Shadman Ali, Sanjana Lamia, Sara Guarino, Emma Halter, Steve Aibel, Heather Manitzas Hill","doi":"10.1002/zoo.70077","DOIUrl":"10.1002/zoo.70077","url":null,"abstract":"<p><p>Enrichment is critical to the welfare needs of animals in human care. For almost 3 years, three species of odontocetes were tested on their discrimination responses to familiar and unfamiliar stimuli using two different presentation formats. The current study was an opportunistic investigation of the effectiveness of these visual experiences as enrichment. The results of this visual enrichment resulted in longer gaze durations when compared to a control condition and gaze durations varied based on the presented stimulus and presentation paradigm used, depending on the species. This enrichment did not elicit habituation within or across sessions, suggesting that the visual stimuli continued to be interesting and attention grabbing even across multiple months and years. Overall, the re-evaluation of a data set derived from a free-swimming discrimination task investigating responses to familiar and unfamiliar visual stimuli under two different presentation paradigms suggested that this type of visual enrichment can be stimulating and reinforcing to these three species. Future research should continue to assess individual visual preferences to better understand the benefits of different forms of enrichment on the welfare of cetaceans in human care.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":"499-512"},"PeriodicalIF":1.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13446422/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147843615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Behavioral Characteristics of an Extremely Old Rhesus Macaque in a Zoo: Dementia-Like Symptoms and Implications for Quality of Life of Geriatric Animals.","authors":"Yumi Yamanashi, Haruna Bando, Keita Niimi, Daisuke Nakagawa, Susumu Iwaide, Tomoaki Murakami","doi":"10.1002/zoo.70074","DOIUrl":"10.1002/zoo.70074","url":null,"abstract":"<p><p>Documenting and understanding the welfare of aging animals are crucial for maintaining their well-being and making appropriate management decisions. This study details the behaviors of an extremely old rhesus macaque (ISK) in which senile plaques and phosphorylated tau deposition were observed in postmortem pathological analyses of the brain. We report on the activity budgets, behavioral rhythms, gait, quality of life (QoL) scores, and anecdotal episodes of this individual. The average 24-h activity budgets, analyzed from surveillance camera recordings, revealed that ISK spent most of her time inactive. ISK was sometimes active at night, though her behavior remained predominantly diurnal. Gait analysis suggested that her movement patterns changed between the first (December 2020) and the last (June 2021) assessment. QoL assessments, using a scoring sheet, indicated relatively good well-being until the later stage of her life. An anecdotal episode, along with the husbandry diary, suggested signs of cognitive decline. These results suggest possible signs of physical decline, and some behavioral changes that could be associated with cognitive decline in an extremely old rhesus macaque. However, we could not confirm cognitive dysfunction without further controlled cognitive testing. We hope that future studies will consider the behavioral symptoms observed in this study as monitoring items to better understand physical and cognitive decline, and possible relationships with QoL in primates.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":"478-486"},"PeriodicalIF":1.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13446417/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147821558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Influence of Zoo Habitat Settings on the Species Diversity and Assemblage of Free-Ranging Animals.","authors":"Eneilsha Nelson Entap, Aizad Faizatul-Azreen, Thirubashini Songodan, Farah Shafawati Mohd-Taib","doi":"10.1002/zoo.70073","DOIUrl":"10.1002/zoo.70073","url":null,"abstract":"<p><p>Zoos worldwide use natural man-made landscapes to enhance visitor experiences while focusing on exhibited animals. These landscapes also attract free-ranging animals. However, the presence of free-ranging animals in zoos has not been thoroughly documented, necessitating further exploration. This study aimed to identify free-ranging mammals and birds in Zoo Melaka, one of Malaysia's oldest zoos with mature natural landscapes and to examine factors influencing their distribution. Point-count observations and cage-trapping were conducted across five zones, recording 11 mammals and 40 bird species. Mammals exhibited a higher Shannon diversity index in closed-enclosure zones (H' = 1.943), although no significant differences were detected between open and closed enclosures (U = 99.5, Z = -0.716, p > 0.1). In contrast, birds showed significantly higher diversity in open enclosures. Overall, enclosure types and habitat zones were significantly correlated with the abundance of free-ranging birds, reflecting the influence of habitat heterogeneity and complexity in providing food and shelter. The presence of several species of conservation concern in the zoo also highlights the role of zoos in supporting biodiversity. These findings indicate that enclosure type, habitat complexity and management strongly shape free-ranging animal communities, with closed enclosures serving as refuges for habitat-sensitive mammals while open enclosures with structurally complex areas favoring birds. Effective management, like control of peri-domestic pest rodents, is crucial to reduce risks particularly zoonotic disease transmission while maintaining balanced and sustainable zoo ecosystems. These results underscore the importance of integrated landscape and enclosure management in promoting the coexistence of free-ranging and captive species in zoo environments.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":"459-477"},"PeriodicalIF":1.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13446420/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147821567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Taxon, Arboreality, Sex, and Season-Factors Influencing Gastrointestinal Parasite Occurrence in Zoo-Housed Non-Human Primates.","authors":"Stalder Sandro, Hatt Jean-Michel","doi":"10.1002/zoo.70063","DOIUrl":"10.1002/zoo.70063","url":null,"abstract":"<p><p>The emergence of anthelminthic resistance is a well-documented phenomenon in livestock and companion animals. Given the scarcity of new antiparasitic drugs, the implementation of effective, holistic anthelminthic control strategies is critical to preserving the efficacy of existing treatments. Understanding parasite-host-environment interactions is necessary to establish such strategies aiming to reduce the use of anthelminthic drugs, mitigate resistance, and ultimately improve animal health and welfare. This study analyzed 3767 fecal parasitological reports from non-human primates housed at a Swiss zoological institution over a 48-year period. Frequency of positive results was analyzed in relation to taxonomy, arboreality, sex, season, and mean monthly temperatures. At least one parasite was detected in 53.2% of the samples, with higher occurrence of protozoa (47.4%) than nematodes (7.8%) and cestodes (0.1%). Due to the large sample number and the extensive study period, it was possible to define taxon-specific parasite susceptibilities. The effect of arboreality on parasite occurrence was found to be negligible. Seasonal trends were evident, with the highest nematode occurrence in summer, whereas protozoa occurrence peaked in spring and winter. Comprehensive monitoring is a fundamental prerequisite for the development and implementation of targeted and effective deworming strategies. Such strategies extend beyond the regular administration of anthelminthics and include integrated management practices, consideration of environmental factors, and, ideally, ongoing monitoring of resistance patterns. A well-designed, holistic deworming strategy not only improves animal health and welfare and reduces the risk of zoonotic transmission but also reinforces a zoo's reputation as a center of conservation and education and contributes to the success of reintroduction programs.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":"371-381"},"PeriodicalIF":1.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13446432/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147515167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Circulating Nutrients in Guanay Cormorants and Peruvian Pelicans From Punta San Juan, Peru.","authors":"Ellen S Dierenfeld, Hillary E Allgood, Michael J Adkesson, Matthew C Allender, Andrea J Fascetti, Susana Cárdenas-Alayza, Marco Cardeña, Sharon L Deem","doi":"10.1002/zoo.70062","DOIUrl":"10.1002/zoo.70062","url":null,"abstract":"<p><p>Resource competition with commercial fisheries and changes in prey availability related to El Niño Southern Oscillation (ENSO) events have adversely affected guanay cormorant (GC, Phalacrocorax bougainvilli aka Leucocarbo bougainvilliorum) and Peruvian pelican (PP, Pelecanus thagus) populations within the Humboldt Current marine ecosystem along coastal Peru. Ecosystem effects from environmental and anthropogenic impacts can result in decreased population sizes and declines in immune function, fecundity, and overall species' health. We measured circulating fat-soluble vitamins A and E, four carotenoids, five trace minerals [Cu, Fe, Mn, Pb, Zn], 13 free fatty acids, and 31 amino acids in GC and PP from Punta San Juan, Peru. We found significant differences in nutrient status between species, sexes, and body weights. There were 82 GC and 34 PP sampled in total: body weights were significantly (p < 0.001) higher in males (2.20 ± 0.15, 6.05 ± 0.47 kg) than females (1.96 ± 0.14, 4.88 ± 0.25) of both species (GC and PP, respectively). Pelicans displayed lower vitamin A concentrations (0.48 ± 0.07 µg/ml) than GC (0.67 ± 0.15 µg/ml) but higher total carotenoids (10.24 ± 2.55 and 5.70 ± 1.87 µg/ml; p < 0.05); vitamin E concentrations did not differ between species (GC 7.74 ± 2.87, PP 8.45 ± 2.16 µg/ml). Within minerals, copper (352.53 ± 206.17, 214.97 ± 25.33 ng/ml) and manganese (11.13 ± 3.85, 8.75 ± 4.36 ng/ml) concentrations were higher and zinc (1.69 ± 0.30, 2.15 ± 0.30 µg/ml) was lower in GC (n = 31) than PP (n = 34), respectively, p < 0.05). Fatty acid (FA) profiles differed between species in that GC had lower levels of circulating EPA (p = 0.026) and DHA (p < 0.001), resulting in lower n-3/n-6 ratios for GC (2.57 ± 0.91) compared with PP (4.69 ± 0.95) (p < 0.001). PP had higher levels of palmitic acid (p < 0.0001). No differences in FA were found between sexes. On the contrary, circulating amino acid (AA) profiles were broadly similar between species for essential AAs, but differed widely for several of the non-essential AAs, suggesting different primary prey items consumed by species and/or sexes. These results provide baseline information on circulating nutrient concentrations and may be useful for comparison of different foraging strategies/prey base use in these sympatric species, as well as for the evaluation of temporospatial variations that may result from anthropogenic causes, including changes in ENSO events. Knowing the diets of these species in the wild helps in providing them with better diets in captivity that could promote health and fecundity.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":"391-404"},"PeriodicalIF":1.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13446418/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147582202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First Non-Invasive Monitoring of Fecal Steroids in Greater Caribbean Manatees (Trichechus manatus manatus).","authors":"Vanessa Bermúdez-Cardona, Roberto Sánchez-Okrucky, José A Sandoval-Zárate, Nataly Castelblanco-Martínez","doi":"10.1002/zoo.70070","DOIUrl":"10.1002/zoo.70070","url":null,"abstract":"<p><p>Reproductive endocrinology plays a crucial role in the management of endangered species. Using non-invasive techniques, the complex nature of their reproductive biology can be better understood. This study aimed to determine hormonal concentrations of progesterone (P4) and estradiol (E2) in female Greater Caribbean manatees (Trichechus manatus manatus) under human care and to establish whether there are differences in hormone concentrations between sexually mature and sexually immature females based on fecal analysis. The assessment of steroid metabolites was performed using the enzyme-linked immunosorbent assay (ELISA) technique with a commercial DetectX kit. The results indicated reference values for progesterone (P4) ranging from 109.9 to 334.3 ng/g feces and for estradiol (E2) ranging from 12.2 to 90.9 ng/g feces. These results suggest an inversely proportional relationship between the two hormones, demonstrating a complex interaction in the estrous cycle of manatees. The findings also indicated no evidence that individual hormonal levels are correlated (Spearman correlation test: ρ = 0.122, p = 0.254; and Kendall correlation test: τ = 0.084, p = 0.245), although higher progesterone levels were associated with lower estradiol concentrations and vice versa. Similarly, no significant correlation was observed between the hormone concentrations of sexually mature and sexually immature females (Skillings-Mack test: P₄, p = 0.103, df = 34, 10,000 repetitions; E₂, p = 0.276, df = 34, 10,000 repetitions). Longer monitoring periods, along with vaginal cytology and ultrasound evaluations, are recommended.</p>","PeriodicalId":24035,"journal":{"name":"Zoo Biology","volume":" ","pages":"435-443"},"PeriodicalIF":1.5,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13446424/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147783254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}