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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Aspectos acústicos da domesticação: os chamados de alerta e de corte do preá Cavia aperea e da cobaia Cavia porcellus. / Acoustic aspects of domestication: vocal signals of alarm and courtship in wild and domestic cavies.

Monticelli, Patrícia Ferreira 28 July 2000 (has links)
A comparação entre cobaias (Cavia porcellus) e preás (Cavia aperea) fornece dados relevantes para se entender o processo de domesticação (Künzl e Sachser, 1999). No presente trabalho, foram registradas e analisadas sonograficamente (1) a vocalização de alerta, drr, em cobaias e em duas amostras de preás, uma observada em Münster (Alemanha), constituída de animais provenientes da Argentina, e outra constituída de animais provenientes de Itu (São Paulo) e (2) a vocalização de corte, purr, em cobaias e preás de Münster. Encontrou-se diferenças significativas entre C. porcellus e ambas as populações de C. aperea nos parâmetros temporais do drr (duração dos pulsos e dos intervalos entre eles e taxa de emissão) assim como diferenças significativas entre as populações de preás de Münster e de Itu (freqüências mínima e máxima da fundamental e freqüência máxima do chamado). No caso do purr, também houve diferenças significativas nos parâmetros temporais das espécies. Estes resultados demonstram a influência da domesticação e de fatores ecotípicos sobre a comunicação vocal e podem, juntamente com a análise sonográfica dos chamados de outras espécies do gênero Cavia, servir para resolução de questões filogenéticas deste grupo. Estudos com playbacks cruzados poderão eventualmente mostrar em que medida as diferenças de vocalização afetam o comportamento social e reprodutivo dos animais. / Comparision of guinea pigs (Cavia porcellus) and wild cavies (C. aperea) provides privileged models for the understanding of the behavioral effects of domestication (Künzl & Sachser, 1999). We here present a comparision between alarm (drr) and courtship (purr) vocalizations in domestic and wild types of cavies. We recorded and analyzed sonographically such calls in guinea pigs from our laboratory stock and in two samples of wild cavies, one from Münster University (Germany), bred from individuals captured in Argentina, and one from Itu (State of São Paulo). There were significant differences between domestic and both wild cavies samples in the temporal features of the drr (pulse duration, interpulse interval duration and rate of emission) and between the Münster and Itu samples in frequency related features (minimum and maximum freqüencies of the fundamental and maximum frequency of the call). Courtship calls purr of domestic and wild cavies from Münster also differed in temporal acoustical features. Our results show that both domestication and ecotypic factors may influence vocal communication. Playback studies could eventually show to what extent there is interspecific discrimination of the acoustic features of the alarm and courtship calls of cavies.
202

Personality Traits in Atlantic Spotted Dolphins (Stenella Frontalis): Syndromes and Predictors of Neophilia

Unknown Date (has links)
Personality is defined as inter-individual variation of behavioral traits while maintaining intra-individual stability. The focus of this study was to observe distinct personality trait categories, establish baseline personality trait phenotypes for the juvenile population, and compare the personality phenotypes between different categories, such as sex or generation. Three personality traits were studied—sociability, curiousity, and boldness—based on the percentage of time individuals spent with conspecifics, human researchers, and their mothers, respectively. The surveyed individuals significantly varied positively and negatively from the means of each trait, and no significant difference for any trait was found between males and females, or across time periods. A moderately strong correlation was discovered between two personality traits, boldness and curiousity, suggesting a personality syndrome. The second primary goal was to use the aforementioned baseline to determine if personality traits can be used to predict neophilic behavior specific to human-dolphin communication research. Six of the study subjects were more prone than their peers to engage with the two-way work, and these individuals were more bold—spent less time with their mothers—than the other subjects. This suggests that boldness has some predictive capabilities towards this type of neophilia. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
203

The Role of Chemical Cues in Locating Pelagic Sargassum by the Associated Fish Stephanolepis hispidus

Unknown Date (has links)
The ecosystem created by pelagic Sargassum is important in the life histories of a number of economically and ecologically important associated organisms. Fishes play a vital role in this food web and nutrient flow within these systems, but it is unknown how they locate these floating habitats. This study examined the role of natural chemical cues from Sargassum patches and the synthetic chemical Dimethylsulfonionpropionate (DMSP) for an associated fish, the planehead filefish (Stephanolepis hispidus) and a control fish species not associated with Sargassum, the masked goby (Coryphopterus personatus). Choice trials with a Y-maze apparatus determined that S. hispidus responded significantly to chemical cues from Sargassum while C. personatus did not. DMSP cues did not result in any significant behavioral responses for either fish. Demonstrating that S. hispidus can respond to chemical cues from Sargassum helps further our understanding of this unique floating algal reef and how fishes may locate it. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
204

Origins, movements, and foraging behavior of Hawksbill Sea Turtles (Eretmochelys imbricata) in Palm Beach County waters, Florida, USA

Unknown Date (has links)
This dissertation examined the natal origins, home-range, and in-situ foraging behavior of an aggregation of sub-adult hawksbill turtles (Eretmochelys imbricata) found off the coast of Palm Beach County, Florida. Surveys were conducted on approximately 30 linear km of reef between 15 and 30 m in depth. Tissue samples were retrieved from 112 turtles for mtDNA haplotype determination. GPS-linked satellite transmitters were deployed on six resident sub-adults, resulting in both minimum convex polygon (MCP) and 95%, 50%, and 25% kernel density estimates (KDE) of home-range size. A foraging ethogram was developed, and sequential analysis performed on thirty videos (141 total minutes) of in-situ foraging behavior. Seventeen total haplotypes were identified in this aggregation, the majority (75%) of which represented rookeries on Mexico’s Yucatan Peninsula. Other sources, from most to least important, include Barbados, Costa Rica, Puerto Rico, Antigua, and the U.S. Virgin Islands. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
205

Cognitive and magnetosensory ecology of the yellow stingray, Urobatis jamaicensis

Unknown Date (has links)
Elasmobranchs (sharks, skates, and rays) migrate across a wide range of spatiotemporal scales, display philopatry, seasonal residency, and maintain home ranges. Many animals use the Earth’s magnetic field to orient and navigate between habitats. The geomagnetic field provides a variety of sensory cues to magnetically sensitive species, which could potentially use the polarity, or intensity and inclination angle of the field, to derive a sense of direction, or location, during migration. Magnetoreception has never been unequivocally demonstrated in any elasmobranch species and the cognitive abilities of these fishes are poorly studied. This project used behavioral conditioning assays that paired magnetic and reinforcement stimuli in order to elicit behavioral responses. The specific goals were to determine if the yellow stingray, Urobatis jamaicensis, could detect magnetic fields, to quantify the nature of the magnetic stimuli it could detect, and to quantify the learning and memory capabilities of this species. The results supported the original hypotheses and demonstrated that the yellow stingray could: discriminate between magnetic and non-magnetic objects; detect and discriminate between changes in geomagnetic field strength and inclination angle; and use geomagnetic field polarity to solve a navigational task. The yellow stingray learned behavioral tasks faster and retained the memories of learned associations longer than any batoid (skate or ray) to date. The data also suggest that this species can classify magnetic field stimuli into categories and learn similar behavioral tasks with increased efficiency, which indicate behavioral flexibility. These data support the idea that cartilaginous fishes use the geomagnetic field as an environmental cue to derive a sense of location and direction during migrations. Future studies should investigate the mechanism, physiological threshold, and sensitivity range of the elasmobranch magnetic sense in order to understand the effects of anthropogenic activities and environmental change on the migratory ability of these fishes. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
206

Selection of canals and ditches as foraging habitat by wood s7374torks (Mycteria americana)

Unknown Date (has links)
A challenge to ensure the health of wading bird populations is to have a better understanding of the altered habitats that we must now consider part of their natural history. Throughout their range endangered Wood Storks (Mycteria americana) have been reported to forage in ditches, a disparate category of linear man-made waterways. In a 52-kmP 2 P study area on the east coast of central Florida, the characteristics of hydrologically diverse ditches were quantified, and their use by Wood Storks documented during their non-breeding season. Logistic regression analyses were carried out using the ditch characteristics as independent variables and Wood Stork presence/absence as the dependent variable. This study confirms the use of these marginal wetlands, and identifies the significance of emergent vegetation on the foraging habitat selection of Wood Storks in the dry season. / by Eleanor K. Van Os. / Thesis (M.S.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2008. Mode of access: World Wide Web.
207

Visual discrimination by C57BL/6J mice in water maze tasks: does size really matter?

Unknown Date (has links)
When interpreting how an animal "learns" discrimination tasks, strain capabilities must be considered, and it should be shown that they comprehend the task in a manner consistent with the given interpretation. A novel visual-discrimination (VD) task for relative-size-relations was used to examine visual cue use in C57BL/6J mice, which are shown to have biologically good vision and neurologically intact memory for VD tasks. Results suggest C57BL/6J strain may not be fully capable of relative cue-size associations or even object recognition-based on a water maze VD task. This is in contrast to previous studies suggesting this mice strain is quite strong in visual skills and on VD tasks. Additionally, cue size and/or cue-pairings do appear to influence specific directional preferences or stereotyped behaviors as trainings continued, and these strategies shifted during novel probes. Future studies should assess how mice discriminate between objects and test rat's capabilities on this task. / by Eric D. Buerger. / Thesis (M.A.)--Florida Atlantic University, 2008. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2008. Mode of access: World Wide Web.
208

Breastfeeding and kangaroo care: biobehavioral measures of dyadic bonding, infant cortical maturation, and infant HPA reactivity

Unknown Date (has links)
The current study examined the effects of kangaroo care on breastfeeding practices, infant stress reactivity, and biobehavioral measures of mother-infant bonding across the first 3 months postpartum. Additionally, the role of breastfeeding in infant cortical maturation in the frontal lobe was examined. Thirty two mother-infant dyads participated in the current study; 16 mother-infant dyads were randomly assigned to the kangaroo care group and 17 mother-infant dyads were assigned to the control group. Mothers in the kangaroo care group received training on proper kangaroo care procedures by a trained administrator during the first 1-2 weeks postpartum. Mothers in the kangaroo care group were asked to use the kangaroo care procedure for 1 hour per day for 6 weeks. Maternal perceptions of fetal attachment, mood, feeding intentions, and urinary oxytocin measurements were assessed prenatally. At a newborn visit, infant neurobehavioral functioning and urinary oxytocin measurements were assessed. Maternal mood and feeding practices were also assessed at the newborn visit. At 3 months postpartum, mother-infant dyads were assessed on urinary oxytocin measurements. Mother-infant dyads were recorded during a play session and feeding session. Infant baseline EEG recordings were taken over a 5 minute period. Infant cortisol measurements were collected from infant saliva before and after a mild behavioral stressor, an infant arm restraint procedure. Maternal perceptions of postpartum bonding, mood, infant temperament, and feeding practices were also assessed. Results indicate that kangaroo care produced medium to large effects on cortisol reactivity, dyadic bonding, and breastfeeding practices if kangaroo care was practiced for the recommended amount of time. Kangaroo care produced medium to large effects on oxytocin levels in motherinfant dyads regardless of use. Cortical measures of infant frontal activity indicated that all infants in the samples displayed functional maturity of the frontal lobe. Kangaroo care can be used a viable, low-cost tactile procedure that can be implemented after birth to aid in breastfeeding practices, mother-infant bonding, and lower infant stress reactivity. Infants in the study who received at least one breastfeeding session displayed advanced patterns of frontal activation. Further study is needed to determine if peripheral oxytocin measurements are 1) reliable and 2) are indicative of dyadic bonding behaviors. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
209

Mapeamento anátomo-funcional dos sítios neurais envolvidos nas respostas observadas durante exposição ao ambiente contextual de uma derrota social. / Anatomic and functional mapping of the neural sites involved in the observed responses during the exposition of the environment of a social defeat.

Rangel Júnior, Miguel José 28 August 2012 (has links)
Neste trabalho elaboramos um paradigma para estudar os comportamentos de defesa ao contexto de uma derrota social e as estruturas neurais envolvidas nas respostas de defesa do animal derrotado utilizando imunohistoquímica para proteína Fos. Utilizou-se um aparato que consistia de uma caixa moradia ligada a outra caixa por um corredor. Houve uma habituação de 10 dias a esse aparato, com a outra caixa contendo apenas maravalha limpa. No 11º dia o animal foi exposto a um macho agressivo colocado na outra caixa, e derrotado por ele. Vinte e quatro horas após a derrota social, os animais derrotados foram expostos ao ambiente em que ocorreu a derrota. Eles apresentaram comportamentos de defesa tanto durante a derrota social quanto durante a exposição ao contexto. No contexto, os derrotados apresentaram comportamentos de avaliação de risco e os controles exploraram livremente o aparato. Notamos um aumento na expressão de proteína Fos no MEApd na amígdala, no LSr no septo lateral, no circuito sexualmente responsivo do hipotálamo medial, na LHAjd no hipotálamo, e no PMD. / We investigated the neural systems involved in the contextual defense to a social defeat. We established a protocol to observe contextual defensive responses in animals previously defeated by an aggressive conspecific: animals were kept ten days living in a apparatus composed by two cages (room and resident cages). On the 11th day animals were exposed to an aggressive conspecific and defeated by it. On the following day, animals were exposed to the apparatus. These defeated animals presented defensive responses, characterized by risk assessment behaviors. Increased Fos expression was found in MEApd, LSr, elements of the social responsive medial hypothalamic circuit, the juxtadorsal part of the lateral hypothalamic area and the dorsal premammillary nucleus (PDMdm). The data allowed us to outline a putative circuit involved in the expression of contextual defense to social defeat, and indicates that both innate and contextual defense to social threat apparently share the same neural circuits.
210

Estudo dos efeitos dos flavonóides provenientes do quiabo (Abelmoschus esculentum) em comportamentos relacionados à ansiedade em camundongos / Study of the effects of flavonoids from okra (Abe/moschus Esculentum) in anxiety-related behavior in mice

Dovichi, Selma Sanches 07 April 2009 (has links)
A ansiedade é uma enfermidade psiquiátrica que acomete milhões de pessoas no mundo todo. Dentre as substâncias que podem ser ligadas ao efeito ansiolítico de ervas medicinais, os flavonóides se destacam porque freqüentemente são detectados nestas ervas. Neste estudo procurou-se avaliar se compostos bioativos da classe dos flavonóides, presentes no quiabo (Abelmoschus esculentum), poderiam exercer atividade ansiolítica, empregando-se modelos comportamentais para análise de ansiedade em camundongos. Avaliou-se a quantidade e a qualidade dos flavonóides do quiabo, evidenciando-se que o quiabo liofilizado possui 16mg do flavonóide rutina/ 100g. Ratos mostraram-se capazes de absorver rutina, quando esta foi perfundida in situ no duodeno destes animais. Os comportamentos relacionados à ansiedade foram a avaliados no Campo Aberto, no Labirinto em Cruz Elevado e na Placa Perfurada após a ingestão de rações com diferentes concentrações de quiabo (4,5; 7 e 10%) por 7, 14 e 21 dias. Camundongos foram tratados com pentilenotetrazol, droga ansiogênica, e diazepam, droga ansiolítica, para comparar os resultados com aqueles de animais que receberam ração com quiabo. Os resultados obtidos no Campo Aberto mostraram que a suplementação dietética com quiabo aumentou o tempo de permanência na zona interna e também o número de quadros percorridos nesta região, de maneira semelhante ao diazepam, o que evidencia um efeito com perfil ansiolítico. No Labirinto, tanto o tempo de permanência, como o número de entradas nos braços abertos aumentaram em camundongos que consumiram rações suplementadas com quiabo e naqueles tratados com diazepam, corroborando os resultados obtidos no Campo Aberto. Na Placa Perfurada, o tempo de latência para o primeiro mergulho em um dos orifícios diminuiu em camundongos que se alimentaram com ração suplementada com quiabo, de modo similar ou superior ao efeito obtido pelo tratamento com diazepam e significativamente menor que o efeito produzido pelo tratamento com pentilenotetrazol. Não foram detectados flavonóides em tecidos biológicos de ratos e camundongos tratados com quiabo ou com rutina. Assim, concluiu-se que a suplementação dietética com o flavonóide rutina, proveniente do quiabo, resultou em efeito ansiolítico em camundongos, mostrando que o enriquecimento da dieta com alimentos ricos em rutina pode contribuir para a prevenção e tratamento do comportamento relacionado à ansiedade em camundongos. / Anxiety is a psychiatric disorder that affects millions of people around the world. Among the substances that may be linked to the anxiolytic effect of medicinal herbs, the flavonoids stand out because they are often found in these herbs. In the present study we sought to evaluate whether the c1ass of bioactive compounds flavonoids, present in okra (Abelmoschus esculentum), could exert anxiolytic activity, using models for behavioral analysis of anxiolytic activity in mice. We evaluate the quantity and quality of flavonoids of okra, showing that the okra lyophilisate has 16mg of flavonoid rutin/100g. Rats were shown able of absorb rutin, when it was perfused in situ in the duodenum of these animals. Behaviors related to anxiety were evaluated in the Open Field, Elevated Plus Maze and Hole Board after the intake of diets with different concentrations of okra (4.5, 7 and 10%) for 7, 14 and 21 days. Mice were treated with pentilenotetrazol, an ansiogenic drug, and diazepam, an anxiolytic drug, to compare the results with those of animals that received diet with okra. The results obtained in the Open Field showed that dietary supplementation with okra increased the permanence in the inner zone and also the number of tables covered in this region, so similar to diazepam, shows a anxiolytic profile. In the Elevated Plus Maze, the time, as the number of entries in open arms increased in mice that consumed diets supplemented with okra and those treated with diazepam, corroborating the results obtained in the Open Field. In the Hole Board, the latency time to first diving in one of the holes decreased in mice that are treated with diet supplemented with okra, so similar to or greater than the effect obtained by treatment with diazepam and significantly smaller than the effect produced by treatment with pentilenotetrazol. Flavonoids were not detected in biological tissues of rats and mice treated with okra or with rutin. Thus, it was concluded that dietary treatment with the flavonoid rutin, from okra, resulted in anxiolytic effect in mice, showing that the enrichment of the diet with foods rich in rutin can contribute to the prevention and treatment of anxiety-related behavior in mice.

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