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Letteratura scientifica selezionata sul tema "Bottlenose dolphin – Reproduction"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 1 febbraio 2022

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Articoli di riviste sul tema "Bottlenose dolphin – Reproduction"

Clarkson, J., F. Christiansen, T. Awbery, L. Abbiss, N. Nikpaljevic e A. Akkaya. "Non-targeted tourism affects the behavioural budgets of bottlenose dolphins Tursiops truncatus in the South Adriatic (Montenegro)". Marine Ecology Progress Series 638 (19 marzo 2020): 165–76. http://dx.doi.org/10.3354/meps13257.

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We investigated the short-term effects of non-targeted tourism on the behaviour of bottlenose dolphins Tursiops truncatus in the South Adriatic off the coast of Montenegro, by comparing dolphin group behaviour during impact (the presence of non-targeted tourism vessels) and control (absence of all marine vessels) scenarios. Tourism vessel and dolphin behavioural data were collected through systematic weekly land-based surveys. Using instantaneous focal ‘group’ scan sampling, the predominant behaviour of bottlenose dolphin groups was determined. To quantify the effect of vessel interactions on the behavioural budget of the dolphins, we followed a stepwise modelling approach. A first-order Markov chain was used to calculate the transition probabilities between behavioural states before a Monte Carlo simulation estimated the behavioural budgets of dolphins during impact and control situations. In the presence of non-targeted tourism, dolphins were found to be less likely to remain diving (during which dolphins were assumed to be feeding), whilst milling-socialising and surface feeding were completely absent from their behavioural repertoires. Nevertheless, the behavioural budgets demonstrated an increase in resting behaviour in the presence of non-targeted tourism vessels. No significant changes to travelling behaviour were observed. The decrease in foraging behaviour (both surface feeding and diving) could result in a reduction in energy intake for dolphins, which over time (assuming repeated disturbance) could negatively affect body condition, and ultimately survival and reproduction. Regulations on non-targeted tourism should therefore be considered to minimise potential long-term negative effects on dolphins within Montenegrin territorial waters.

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Sanchez-Calabuig, M. J., J. de la Fuente, P. Beltrán-Breña, E. Martinez-Nevado, J. F. Perez-Gutierrez, D. Blyde, S. Johnston, K. Harrison, C. Lopez-Fernandez e J. Gosalvez. "170 ASSESSMENT OF FRESH AND FROZEN - THAWED BOTTLENOSE DOLPHIN (TURSIOPS TRUNCATUS) SPERM DNA FRAGMENTATION USING THE SPERM CHROMATIN DISPERSION TEST". Reproduction, Fertility and Development 25, n. 1 (2013): 233. http://dx.doi.org/10.1071/rdv25n1ab170.

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There has been significant development over the last 20 years to improve genetic management of the captive bottlenose dolphin (Tursiops truncatus) by means of genome resource banking and assisted reproduction. Although standard semen parameters have been analysed in some detail, very little is known about sperm DNA fragmentation (SDF) in this species. The aim of this study was to develop a sperm chromatin dispersion test (SCDt) for the bottlenose dolphin to establish the baseline level of SDF immediately after ejaculation and cryopreservation and to determine the dynamic loss of sperm DNA quality after ex vivo handing and incubation in conditions that mimic the female reproductive tract. Semen from 8 bottlenose dolphins was collected by manual stimulation. Initial validation of the SCDt was conducted by means of in situ nick translation and neutral comet assay using a proven fertile male. To investigate the dynamic loss of sperm chromatin (rate of sDF loss), thawed sperm samples were incubated at 37.9°C for up to 48 h, and aliquots of spermatozoa were assessed after 1, 4, 8, 24, and 48 h. Dolphin sperm nuclei with fragmented DNA exhibited large halos of dispersed DNA fragments, whereas those with nonfragmented DNA displayed small halos of nondispersed DNA. A high correlation (r2 = 0.82; P ≤ 0.01) was found between the respective assessments of the SCDt and the neutral comet assay. All nucleoids resulting in a large halo of dispersed chromatin were intensely positive to in situ nick translation. The level of sDF fragmentation observed immediately after ejaculation in fresh and frozen samples was relatively low (1–5%). After comparing different ejaculates of the same individual, differences were found. Chromatin stability was high during the first 48 h of ejaculation or post-thawing and incubation. Evaluation of the sDF dynamics of fresh and frozen–thawed spermatozoa revealed no significant increase in the baseline level of sDF or in the relative increase of DNA damage after 48 h of incubation. Our data suggest that cryopreservation does not induce a dramatic increase in sperm chromatin damage. Interestingly, sperm samples derived from aged animals resulted in an increased rate of DNA loss, which was observed after 60 min post-incubation.

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Vermeulen, Els, Ricardo Bastida, Leonardo G. Berninsone, Pablo Bordino, Mauricio Failla, Pedro Fruet, Guillermo Harris et al. "A review on the distribution, abundance, residency, survival and population structure of coastal bottlenose dolphins in Argentina". Latin American Journal of Aquatic Mammals 12, n. 1-2 (2 marzo 2018): 2–16. http://dx.doi.org/10.5597/00233.

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Although bottlenose dolphins Tursiops truncatus are among the most common delphinid species, global population trends remain poorly understood. To improve the knowledge of the species in the Southwest Atlantic Ocean, thispaper reviews all available data related to the distribution and occurrence, abundance, residency and ranging patterns, group size and composition, survival and reproduction and population structure of the coastal bottlenose dolphin in Argentina. Most information proved to be scattered in time and space. Based on the available data, total abundance of coastal bottlenose dolphins in Argentina appears to be low. Data show sightings decreased notably since the 1990s in the northern province of Buenos Aires and the province of Chubut, with the species having disappeared completely from the former region. Data also indicated that two genetically and morphologically distinct coastal populations occur in Argentinean coastal waters, with a sympatric distribution in the provinces of Río Negro and Chubut. One is an isolated ‘Evolutionary Signifcant Unit’ within the larger Southwest Atlantic, whereas the other population appears to be genetically related to the Southwest Atlantic oﬀshore ecotype. In the absence of more substantial data, the present information is pertinent to our scientifc knowledge of the species in the country, collating all published information as well as information from grey literature and previously unpublished data. However, the available information appears to remain insufcient to explain the apparent decline in sightings and to assess the remaining abundance nationwide accurately. Therefore, we strongly recommend increased research eﬀorts for an in-depth assessment of the species’ population status in Argentina.

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Lane, Suzanne M., Cynthia R. Smith, Jason Mitchell, Brian C. Balmer, Kevin P. Barry, Trent McDonald, Chiharu S. Mori et al. "Reproductive outcome and survival of common bottlenose dolphins sampled in Barataria Bay, Louisiana, USA, following the Deepwater Horizon oil spill". Proceedings of the Royal Society B: Biological Sciences 282, n. 1818 (7 novembre 2015): 20151944. http://dx.doi.org/10.1098/rspb.2015.1944.

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Common bottlenose dolphins ( Tursiops truncatus ) inhabit bays, sounds and estuaries across the Gulf of Mexico. Following the Deepwater Horizon oil spill, studies were initiated to assess potential effects on these ecologically important apex predators. A previous study reported disease conditions, including lung disease and impaired stress response, for 32 dolphins that were temporarily captured and given health assessments in Barataria Bay, Louisiana, USA. Ten of the sampled dolphins were determined to be pregnant, with expected due dates the following spring or summer. Here, we report findings after 47 months of follow-up monitoring of those sampled dolphins. Only 20% (95% CI: 2.50–55.6%) of the pregnant dolphins produced viable calves, as compared with a previously reported pregnancy success rate of 83% in a reference population. Fifty-seven per cent of pregnant females that did not successfully produce a calf had been previously diagnosed with moderate–severe lung disease. In addition, the estimated annual survival rate of the sampled cohort was low (86.8%, 95% CI: 80.0–92.7%) as compared with survival rates of 95.1% and 96.2% from two other previously studied bottlenose dolphin populations. Our findings confirm low reproductive success and high mortality in dolphins from a heavily oiled estuary when compared with other populations. Follow-up studies are needed to better understand the potential recovery of dolphins in Barataria Bay and, by extension, other Gulf coastal regions impacted by the spill.

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Blasi, MF, C. Bruno e L. Boitani. "Female reproductive output in a Mediterranean bottlenose dolphin Tursiops truncatus population". Aquatic Biology 29 (17 settembre 2020): 123–36. http://dx.doi.org/10.3354/ab00732.

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The reproductive output of wild bottlenose dolphins Tursiops truncatus has extensively been investigated; nevertheless, it remains widely unexplored in the Mediterranean Sea. We investigated the reproductive history of female bottlenose dolphins in the Aeolian Archipelago (Italy). Thirteen years of photo-identification data were used to track the reproductive pattern of 7 females and their 16 calves. The birth period was accurately estimated within 1 mo for 6 calves (37.5%), peaking in June/July. The mean number of calves for females was 2.3 ± 1.1 (SD), ranging from 1 to 4. The mean interbirth interval was 3.5 ± 1.6 yr, ranging from 2 to 7 yr. The mean weaning age was 3.2 ± 0.6 yr, although 1 calf may have been weaned as late as its fifth birthday. Mother-calf postweaning associations were tracked for 9 calves and ranged from 4 to 10 yr of residence in the maternal group of the calf. The age of first pregnancy was 7.5 yr. The number of calves was influenced by the mean maternal group size, with females that were sighted in larger groups having more calves. However, the number of calves was not influenced by the strength of the associations of mothers with other females. Calf mortality by age 1 was high (12.5%). Two juveniles also died postweaning within 6 yr of their birth. Finally, 2 females may have died during the study, as they were not re-sighted at the end of the study. Our results highlight the need to implement urgent conservation actions to protect this bottlenose dolphin population.

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Mann, Janet, Andrew F. Richards, Rachel A. Smolker e Richard C. Connor. "Patterns of Female Attractiveness in Indian Ocean Bottlenose Dolphins". Behaviour 133, n. 1-2 (1996): 37–69. http://dx.doi.org/10.1163/156853996x00026.

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AbstractHormonal profiles of captive individuals show that bottlenose dolphins (Tursiops spp.) are seasonally polyoestrous, but little is known of reproductive behaviour among free-ranging bottlenose dolphins. In Shark Bay, Western Australia, we have documented for the first time patterns of female attractiveness that may correspond to multiple oestrous cycles. Male bottlenose dolphins in stable alliances of 2-3 individuals form temporary consortships with individual females. Consortships often are established and maintained by aggressive herding. Consortships are associated with reproduction and are a useful measure of a female's attractiveness. Following reproduction, females may become attractive to males when their surviving calf is about 2-2.5 years old or within 1-2 weeks of losing an infant. Individual females are attractive to males for variable periods extending over a number of months, both within and outside of the main breeding season. The duration of attractive periods is greater during breeding season months than during the preceding months. Males sometimes are attracted to females for periods exceeding the reported duration of rising estrogen levels during the follicular stage of the oestrous cycle. Males occasionally have consorted or otherwise been attracted to females in several unusual contexts, including late pregnancy, the first two weeks after parturition, and the day after the loss of a nursing infant. Individual females were consorted by up to 13 males during the season they conceived, supporting predictions of a promiscuous mating system in bottlenose dolphins. Thus, consorting is a strategy by males to monopolize females, but not a completely successful one. Multiple cycling by female bottlenose dolphins may be a strategy to avoid being monopolized by particular males. Given the duration and agonistic nature of many consortships, the benefits to females of such a costly strategy are not obvious. Multiple cycling may reduce the risk of infanticide by males or allow females to mate with preferred males after being monopolized by less desirable males.

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Möller, Luciana M., e Robert G. Harcourt. "Shared Reproductive State Enhances Female Associations in Dolphins". Research Letters in Ecology 2008 (2008): 1–5. http://dx.doi.org/10.1155/2008/498390.

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Female bottlenose dolphins (genusTursiops) usually associate at moderate level with other females within social clusters called bands or cliques. It has been suggested that reproductive state may play the predominant role in determining associations within femaleT. truncatusbands. Here, we test the hypothesis that reproductive state correlates with associations of female Indo-Pacific bottlenose dolphins (T. aduncus). We found that females in similar reproductive state, which included females from late pregnancy to the first year of their calves' life or females from early pregnancy to their calves' newborn period, had higher-association coefficients with each other than they did with females in different reproductive states (females with older calves or without calves). This was observed both within and across social clusters suggesting that reproductive state, at least for pregnant females and those with young calves, plays an important role in determining who to associate with. However, a female's most frequent associate was not always with another in similar reproductive state. We suggest that several factors, including reproductive state, may be of importance in determining associations of female bottlenose dolphins.

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Bergfelt, Don R., Jason L. Blum, Jill R. Ratner, Marcelo H. Ratto, Justin K. O'Brien e Todd R. Robeck. "Preliminary Evaluation of Seminal Plasma Proteins and Immunoreactivity of Nerve Growth Factor as Indicative of an Ovulation Inducing Factor in Odontocetes". Journal of Zoo Biology 2, n. 1 (22 dicembre 2019): 21–29. http://dx.doi.org/10.33687/zoobiol.002.01.2608.

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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 (β-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 β-NGF is in low abundance in the seminal plasma of belugas and Pacific white-sided and bottlenose dolphins.

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Senigaglia, Valeria, e Lars Bejder. "Pregnancy Cravings: Visitation at a Food-Provisioning Site is Driven by the Reproductive Status of Bottlenose Dolphins". Tourism in Marine Environments 15, n. 3 (14 ottobre 2020): 237–48. http://dx.doi.org/10.3727/154427320x15943283422072.

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Marine wildlife tourism attractions often use food rewards to ensure close-up encounters with freeranging animals. In Bunbury, Western Australia, the Dolphin Discovery Centre (DDC) conducts a foodprovision program where bottlenose dolphins (N = 22; between 2000 and 2018) are offered food rewards to encourage their visitation at a beach in front of the DDC. We used historical records on individual beach visits by adult female dolphins collected by the DDC from 2000 to 2018 to develop generalized mixed effects models (GLMM) to test whether the frequency of beach visitation was influenced by their reproductive status (pregnant, lactating, nonreproductive) or climatic events (El Niño-Southern Oscillation phases) that could affect prey availability. We also quantified the behavioral budget of dolphins during food-provisioning sessions and documented intra- and interspecific aggressive behaviors using individual focal follows collected in 2017–2018. Provisioned females spend most of the time resting within the interaction area (66.3%) and aggressive interactions arise as a consequence of dominance behavior over food access. Visitation rates were most influenced by reproductive status with pregnant and lactating females visiting the provisioning area more frequently (z = 2.085, p = 0.037 and z = 2.437, p = 0.014, respectively). Females that frequently visit the provisioning area expose their dependent calves to regular human interactions at an early age when they are more susceptible to behavioral conditioning. Such experiences could cause the loss of awareness towards humans and promote maladaptive behaviors such as begging that increase risk of entanglement in fishing gear, boat strikes, and propeller injuries.

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Saviano, Pietro, Letizia Fiorucci, Francesco Grande, Roberto Macrelli, Alessandro Troisi, Angela Polisca e Riccardo Orlandi. "Pregnancy and Fetal Development: Cephalic Presentation and Other Descriptive Ultrasonographic Findings from Clinically Healthy Bottlenose Dolphins (Tursiops truncatus) under Human Care". Animals 10, n. 5 (24 maggio 2020): 908. http://dx.doi.org/10.3390/ani10050908.

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Ultrasonography is widely used in veterinary medicine for the diagnosis of pregnancy, and can also be used to monitor abnormal pregnancies, embryonic resorption, or fetal abortion. Ultrasonography plays an important role in modern-day cetacean preventative medicine because it is a non-invasive technique, it is safe for both patient and operator, and it can be performed routinely using trained responses that enable medical procedures. Reproductive success is an important aspect of dolphin population health, as it is an indicator of the future trajectory of the population. The aim of this study is to provide additional relevant data on feto-maternal ultrasonographic monitoring in bottlenose dolphin (Tursiops truncatus) species, for both the clinicians and for in situ population studies. From 2009 to 2019, serial ultrasonographic exams of 11 healthy bottlenose dolphin females kept under human care were evaluated over the course of 16 pregnancies. A total of 192 ultrasound exams were included in the study. For the first time, the sonographic findings of the bottlenose dolphin organogenesis and their correlation with the stage of pregnancy are described. Furthermore, this is the first report that forecasts the cephalic presentation of the calf at birth, according to its position within the uterus.

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Più fonti

Tesi sul tema "Bottlenose dolphin – Reproduction"

Reddy, Kasturi. "The reproduction biology of four species of South African dolphins". Thesis, Rhodes University, 1996. http://hdl.handle.net/10962/d1005441.

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Seasonality of reproduction in common dolphins (Delphinus delphis), bottlenosed dolphins (Tursiops aduncus), striped dolphins (Stenella coeruleoalba) and humpbacked dolphins (Sousa chinensis) was examined using standard light microscope techniques. In the males four stages of testicular development could be identified. Individuals less than 2.26m in length and 105kg in mass had testes that contained small seminiferous tubules (0.048mm ± O.Olmm in diameter) and were classified either as juveniles (gonocytes present) or inactive (no gonocytes). Adults whose testes contained spermatozoa were said to be in late spermatogenesis while those whose testes contained no spermatids or spermatozoa were referred to as being in early spermatogenesis. In the males of D. delphis, T. aduncus and S. chinensis, late spermatogenesis occurred throughout the year and there was no significant difference in the monthly mean seminiferous tubule diameters (p > 0.05) within species. I conclude therefore that in these three species spermatogenesis is aseasonal. No conclusions about seasonality of spermatogenesis could be made for S. coeruleoalba owing to the small sample size. Large Graafian follicles occurred in the ovaries of all four species in most months of the year. However, the presence of Graafian follicles can not be taken as an indication of timing of reproduction since they may be remnants of follicles that have not yet degenerated. In D. delphis, T. aduncus and S. coeruleoalba luteal bodies (corpora albicans or corpora lutea) occurred in most months of the year. Active corpora lutea will be present in all months, in some members of the population, since gestation is approximately 12 months. The sperm structure of D. delphis was examined by scanning electron microscopy. The sperm of D. delphis is essentially similar to that described for two other species of Cetacea (Physeter catodon and Tursiops aduncus), having an ellipsoidally shaped head and a short mid-piece with nine mitochondria. The sperm dimensions for D. delphis were head length, 4.4pm; head width, 2.0pm and mid-piece length, 2.4pm. An analysis of foetal age in D. delphis showed that the majority of the foetuses were conceived in January with birth occurring the following summer (December), suggesting that reproduction is seasonal. Neonates of T. aduncus were found throughout the year suggesting aseasonal reproduction. Foetal material was not available for S. coeruleoalba and S. chinensis. Seasonality of reproduction in the four species of dolphins studied has been discussed in relation to feeding, migration and worldwide distribution of the species.

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Amir, Omar A. "Biology, ecology and anthropogenic threats of Indo-Pacific bottlenose dolphins in east Africa". Doctoral thesis, Stockholm : Department of zoology, Stockholm university, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-34472.

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Diss. (sammanfattning) Stockholm : Stockholms universitet, 2010.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 4: In progress. Paper 5: Submitted.

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Schulz, Benjamin [Verfasser], Detlef [Gutachter] Rath e Geert [Gutachter] Opsomer. "Investigations into Sperm Sex-Sorting and Reproductive Seasonality in Bottlenose Dolphins / Benjamin Schulz ; Gutachter: Detlef Rath, Geert Opsomer". Hannover : Stiftung Tierärztliche Hochschule Hannover, 2020. http://d-nb.info/1224882938/34.

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Wade, Leslie Schwierzke. "Assessment of Fertility Potential in Bottlenose Dolphins (Tursiops truncatus): An ELISA-based Biomarker Analysis". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3399.

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As apex predators in coastal systems, bottlenose dolphins (Tursiops truncatus) are susceptible to persistent organic pollutant (POP) accumulation and retention over time, which has prompted continued interest in understanding the extent to which contaminant body burdens or other stressors are sufficient to cause adverse sublethal effects on energetic fitness, immune function, or reproduction. Increasing our knowledge of reproductive endocrinology in bottlenose dolphins may provide insight into changes in reproductive rates, thereby expanding the capacity to assess conservation status. This study used the Enzyme-Linked ImmunoSorbent Assay (ELISA) technique to examine peptide fertility hormones [inhibin A, inhibin B and anti-Müllerian hormone (AMH)] measured in serum of free-ranging dolphins (n = 129) of varying age, gender, and maturity status from three locations (Sarasota Bay, FL, Indian River Lagoon, FL, and southern Georgia). The primary research objectives were to establish hormone baselines, investigate AMH and inhibin use as reproductive biomarkers, and examine the potential use of these hormones as biomarkers of toxicant or other stressor effects on reproduction. AMH secretion differed significantly with gender (p < 0.001), where levels were approximately 1,000-fold higher in males than females (1,122 ± 427 ng mL-1 and 1.15 ± 1.25 ng mL-1, mean ± SD). Male AMH levels were related to maturity status, and linear regression analysis revealed a significant, negative relationship between male AMH and age, body length, body weight, and maximum girth in all populations. Of the parameters assessed, age was the best indicator of AMH levels in males. AMH concentrations in females did not vary significantly over time or with maturity status, but exhibited a decrease in some older individuals, potentially indicating an AMH decline in long-lived female dolphins. Inhibins did not differ significantly between age classes in males, but appeared to be an estrous cycle indicator in females, where inhibin peaks were likely related to follicular and luteal phases. These data provide new information on circulating serum AMH and inhibin levels in bottlenose dolphins, which appear to reflect a degree of gonadal function and show promise as reproductive biomarkers. Our findings suggest the possibility of toxicant effects on AMH and inhibin production, but not conclusively. Further investigation of mechanism(s) of action for contaminant-related reproductive toxicity will elucidate the diagnostic value of these hormones to assess the effects of POPs on fertility potential in bottlenose dolphins.

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Tezanos, Pinto Gabriela. "Population structure, abundance and reproductive parameters of bottlenose dolphins (Tursiops truncatus) in the Bay of Islands (Northland, New Zealand)". Thesis, University of Auckland, 2009. http://hdl.handle.net/2292/5799.

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Bottlenose dolphins (Tursiops truncatus) occupy a wide range of coastal and pelagic habitats throughout tropical and temperate waters worldwide. Around New Zealand, bottlenose dolphins inhabit three discontinuous regions in the north-eastern coast of the North Island, Marlborough Sound and Fiordland in the South Island. All these populations are subject to anthropogenic activities including dolphin-based tourism industry. Along the north-eastern coast of the North Island, the Bay of Islands presents a unique opportunity to study this population because of regular occurrence year-round and a history of long-term studies conducted in the region. This study examines the population structure and genetic diversity of the three New Zealand bottlenose dolphin populations to define their boundaries. Second, it focuses on the Bay of Islands subpopulation to investigate the dynamics of dolphin groups, pattern of habitat use, abundance and trends over time. Finally, it estimates reproductive parameters of female bottlenose dolphins to predict the long-term viability of the Bay of Islands subpopulation.

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Thayer, Victoria Graves. "Life History Parameters and Social Associations of Female Bottlenose Dolphins (Tursiops Truncatus) in North Carolina, USA". Diss., 2008. http://hdl.handle.net/10161/609.

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Rapporti di organizzazioni sul tema "Bottlenose dolphin – Reproduction"

Schwacke, Lori. The Bottlenose Dolphin (Tursiops truncatus) as a Model to Understand Variation in Stress and Reproductive Hormone Measures in Relation to Sampling Matrix, Demographics, and Environmental Factors. Fort Belvoir, VA: Defense Technical Information Center, settembre 2012. http://dx.doi.org/10.21236/ada573796.

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Wells, Randall S. The Bottlenose Dolphin (Tursiops truncatus) as a Model to Understand Variation in Stress and Reproductive Hormone Measures in Relation to Sampling Matrix, Demographics, and Environmental Factors. Fort Belvoir, VA: Defense Technical Information Center, settembre 2012. http://dx.doi.org/10.21236/ada573926.

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Schwacke, Lori. The Bottlenose Dolphin (Tursiops truncatus) as a Model to Understand Variation in Stress and Reproductive Hormones Measures in Relation to Sampling Matrix, Demographics, and Environmental Factors. Fort Belvoir, VA: Defense Technical Information Center, settembre 2014. http://dx.doi.org/10.21236/ada616549.

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Wetzel, Dana L. Biomarkers to Assess Possible Biological Effects on Reproductive Potential, Immune Function, and Energetic Fitness of Bottlenose Dolphins Exposed to Sounds Consistent with Naval Sonars. Fort Belvoir, VA: Defense Technical Information Center, settembre 2012. http://dx.doi.org/10.21236/ada573927.

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