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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.
21

The Nutritional Ecology of Adult Female Blue Monkeys, Cercopithecus mitis, in the Kakamega Forest, Kenya

Takahashi, Maressa January 2018 (has links)
The search for food and adequate nutrition determines much of an animal's behavior, as it must ingest the macronutrients, micronutrients, and water needed for growth, reproduction and body maintenance. These macro- and micronutrients are found in varying proportions and concentrations in different foods. A generalist consumer, such as many primates, faces the challenge of choosing the right combination of foods that confers adequate and balanced nutrition. Diet selection is further complicated and constrained by antifeedants, as well as digestive morphology and physiological limitations. Nutritional ecology is the study of the connected relationships between an organism, its nutrient needs (determined by physiological state), its diet selection, and the foraging behavior it uses within a specific food environment. Additionally, these relationships are complex and changeable since the nutrient needs of a consumer change over time and food resources (including the nutritional composition) vary spatiotemporally. Published data on primate nutritional ecology are limited, with most investigations of nutritional needs stemming from captive populations and few field studies. To contribute to the body of knowledge of nutritional ecology in natural populations, I examined the nutritional ecology of wild adult female blue monkeys, Cercopithecus mitis. I used the geometric framework (GF) to quantify nutritional patterns, as it allows simultaneous examination of multiple nutrients that may be driving foraging behavior and patterns of food intake. Blue monkeys are known to be generalist feeders, with flexible feeding behavior. The population I studied inhabits the Kakamega Forest, western Kenya. This forest has a history of variable human modification on a small scale, and offered a unique opportunity to examine environmental factors (e.g. degree of human-modification of forest type, food availability), social factors (dominance rank), and physiological factors (reproductive demand) that may alter blue monkey nutritional strategies. From January and September 2015, a team of field assistants and I collected behavioral data from 3 study groups, intensively sampling 24 adult females that varied in dominance rank and reproductive condition. I used all-day focal follows to quantify feeding behavior, which allowed me to assess diet selection and nutrient intake on a daily basis. I also monitored subjects' daily movement. To assess food availability, I quantified vegetative differences among major habitat types within each group's home range and monitored biweekly changes in plant production of fruits and young leaves, which were major constituents of the plant-based diet. I collected >300 food samples, as well as fecal samples, and analyzed them for macro-nutritional content using wet chemistry and near-infrared spectroscopy techniques. I combined data to examine patterns in diet and nutritional strategy on different scales: patterns across subjects, between groups and within the population as a whole, patterns in the diet on the food composition level versus nutrient intake level, and patterns in nutrient intake on a daily basis versus a long term basis (i.e. over the course of the study period). Additionally, I evaluated factors that might affect variation in nutritional strategies, including a female's reproductive condition, dominance rank, habitat use, and degree of frugivory or folivory in daily intake, as well as food availability in the environment. Kakamega blue monkeys ate a broad diet of over 445 food items (species-specific plant parts and insect morphotypes). Fruit was preferred food, and particular species-specific fruits constituted the majority of important food items (i.e., those contributing >1% of total caloric intake by group); many fruits were highly selected (i.e. eaten more than expected based on availability). Many species-specific young leaves also were important food items, though they were eaten in proportion to their availability, or even less often. Regardless of whether group diet was characterized by time spent feeding or by calories, fruit remained the largest constituent and young leaves the second largest. A subject's daily path length was negatively related to proportion of fruit in the diet (by kcal) because females focused feeding in particular trees when important fruits ripened and thus traveled less. Daily path length was not related to group size, probably because females spread out when foraging to avoid within-group scramble competition over food. Group differences in the food composition of diets likely reflected habitat differences in food distribution. Comparison of the population's diet to data from previous studies showed that as study groups moved into new areas and habitats, they capitalized on new food resources, reinforcing the idea that blue monkey are flexible feeders. During this study, subjects adjusted their diet in response to food availability in the environment, consuming more fruit (by percentage of diet and absolute kcal) when fruit was more available. In contrast, subjects ate fewer young leaves (by absolute kcal) when either fruit or young leaves were more available, suggesting that young leaves served as fallback food. At the level of nutrient intake, it was also true that females consumed significantly more structural carbohydrates when fruit availability was low. Despite their diverse diets and changes related to food availability, females actively regulated food intake to converge daily on a similar nutrient intake (grand mean of 637 kcal, with 108 kcal from protein, 149 kcal from lipid, 88 kcal from structural carbohydrates, and 293 kcal from non-structural carbohydrates, N=24). Thus, considering a multidimensional nutritional niche, I characterized their feeding behavior at two levels: they were both food composition generalists and nutrient intake specialists. Blue monkeys showed a nutritional strategy on two different temporal scales: 1) daily protein prioritization and 2) long term non-protein energy (NPE; i.e. lipid + carbohydrate energy) to available protein (P) balancing. On a daily basis, protein intake (by kcal) showed the least amount of variation (by coefficient of variation) and subjects consumed similar amounts of protein, regardless of potential influences from environmental, social or physiological factors. Females allowed more variation in daily ratio of non-protein energy to protein (NPE:P), taking advantage of high NPE foods like fruit. They allowed higher NPE:P ratios when fruit was a larger proportion of their diet and when they spent less time in near-natural forest. There was no evidence that reproductive demand or dominance rank affected protein intake or NPE:P balance. Dominance rank also did not predict deviation (absolute or directional) from mean protein intake or mean NPE:P ratio. On a long term basis (i.e. over the 8 months of data collection), all subjects tightly balanced cumulative NPE:P intake, regardless of dominance rank. This long-term pattern in all 24 subjects suggests that it a species-typical strategy. However, lower ranking females ate more unique food items per day than higher ranking females. Varying daily dietary breadth may allow females to cope with social constraints while feeding, such that dominance rank had no effect on nutritional strategies. Further, the prevalence of NPE:P balancing in most nutritional ecology studies of primates suggests that the diversity of feeding strategies within this order of mammals may have evolved to allow them to adhere to that particular nutrient balance, though the rule of compromise (e.g. protein versus NPE prioritization) and the exact ratio balanced may differ by population or species. Blue monkeys regularly used human-modified habitats and ate considerable amounts of the non-natural foods found there (and elsewhere in the forest). Non-natural foods were directly derived from humans or human activity (e.g. via scavenging from trash) and exotic (non-native) plants, generally introduced inadvertently or for silviculture. Subjects incorporated a substantial amount of non-natural foods into their diets, with approximately a third of their daily calories derived from non-natural foods. Subjects in the group with the most access to human-modified habitat used non-natural foods the most extensively. Further, subjects in two groups showed clear preference for human-modified habitat while members of the third group used habitat types in proportion to their occurrence in the home range. Human-modified habitat, and the non-natural foods found within, may have been readily used because many non-natural foods provided similar access to nutritional space as natural foods. Some non-natural foods, like oil palm fruit and ugali (cooked maize flour), represented energetically dense food resources, which also proved attractive. Regardless of whether subjects fed primarily on natural or non-natural foods, they consumed similar amounts of daily protein. This prioritization of protein, coupled with the fact that females had higher NPE:P ratios when feeding mostly on non-natural foods, indicated that blue monkeys capitalized on non-natural resources to increase NPE intake as long as they were able to consume a threshold amount of protein. What remains unclear though, is whether there are adaptive advantages associated with the ability to consume diets of variable NPE:P ratios. Overall, blue monkeys in Kakamega Forest are very flexible feeders, perhaps to a greater degree than previously acknowledged. Subjects were able to consume a diverse diet of hundreds of species-specific food items, to shift their diet in response to changes in food availability, to capitalize on food resources found in different habitat types, to take advantage of non-natural food resources, and to tolerate a wide range of NPE:P ratios in daily diets. Further, on a nutritional level, they successfully navigated potential stressors from the physiological demands of reproduction and dominance rank to adhere to a particular nutritional strategy. Flexible behavior, such as spreading out during feeding or varying dietary breadth, indicates how blue monkeys may use particular feeding strategies to arrive at a common nutrient intake target. Despite daily fluctuations in NPE:P ratio that varied with environmental and dietary factors, all subjects were able to consume a consistent daily amount of protein and prioritized its intake above all other nutritional components. Finally, their tight adherence to long term NPE:P balancing suggested that they followed a nutritional strategy that operated on both daily and longer timescales. Primates are increasingly threatened from habitat loss, degradation and other human-disturbances. There is growing awareness that some species, like blue monkeys, may be able to persist in regenerating human-modified landscapes, where they regularly and readily use non-natural food resources. More species- and habitat-specific nutritional studies are needed to predict population-level responses to varying degrees of habitat alteration. The data generated may help us assess the potential value of human-modified habitats that may require protection, as these habitats may contribute to the persistence of primate populations around the globe, especially in novel ecosystems.
22

DIETARY VARIABILITY IN A GROUP OF MIXED-SPECIES CERCOPITHECUS MONKEYS (CERCOPITHECUS MITIS, C. ASCANIUS AND C. MITIS X C. ASCANIUS) IN MKENKE VALLEY, GOMBE NATIONAL PARK, TANZANIA

Unknown Date (has links)
This research represents the first multi-year investigation of the feeding ecology of Gombe’s Cercopithecus populations. The main goal of this study was to identify dietary overlap and distinctiveness among the phenotypes in our study group, a mixed species group of guenons comprised of C. ascanius, C. mitis, and C. ascanius x C. mitis hybrids. Field assistants collected feeding data using ad libitum observations as well as instantaneous scan sampling at 30-minute intervals from July 2014 to December 2018. A total of 63 plant species were identified in our group’s diet. Results indicate that a significant difference exists between the diets of each phenotype. The results also found an unusually high percentage of invertebrate eating (54%) in our group. These findings suggest that invertebrates are an important food resource for the Gombe study group and may help facilitate coexistence in an environment where there are many sympatric primate species. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection
23

The expression of neurofilament protein and mRNA levels in the lateral geniculate nucleus and area V1 of the developing and adult vervet monkey (Ceorcopithicus aethiops) /

Kogan, Cary. January 1999 (has links)
This study comprised three questions, each posed with the intention of exploring the expression of the neurofilament protein (NF) and mRNA levels in the monkey lateral geniculate nucleus (LGN) and visual cortex. (1) Literature indicates NFs are differentially expressed across the two visual pathways that originate from magnocellular and parvocellular layers in LGN. The results herein suggest that this difference continues at the level of gene transcription for the neurofilament heavy gene. (2) NF expression, assessed by SMI-32 (an antibody that recognizes an epitope of the non-phosphorylated NFs), was investigated as a function of developmental changes occurring during the critical period in area V1 of the vervet monkey visual cortex. The findings indicate that the M pathway develops before the P pathway. (3) The effect of eye enucleation on long-term changes in NF expression was investigated. The results do not support the idea that NF are activity-dependent.
24

Gastrointestinal parasites of the vervet monkey (Chlorocebus [Cercopithecus] aethiops) at a sanctuary in Limpopo Province, South Africa

Wren, Brandi T. January 2006 (has links)
Fifty-eight fecal samples from vervet monkeys (Chlorocebus [Cercopithecus] aethiops) at a sanctuary near Tzaneen, Limpopo Province, South Africa, were collected and analyzed to determine which species of gastrointestinal parasites they harbored, and differences in infection rates were examined. Three parasites were found, including two nematodes (Trichuris trichiura and one tentatively classified as Strongyloides spp.) and one protozoa (Balantidium coli). Rates of B. coil and Strongyloides spp. infection were similar in captive (41.9% and 77.4%, respectively) and wild (35% and 75%, respectively) monkeys, but rates of T. trichiura infection were significantly higher in wild individuals. No captives were infected with T. trichiura, but 15% of wild monkeys were infected. Although humans in other regions of South Africa have already been found to harbor two of these parasites (Strongyloides spp. and T. trichiura), caution should still be taken in areas that experience high rates of human-vervet interaction or conflict. Also, evidence suggests that the vervets may have been exposed to B. coil from a nearby pig farm, indicating that humans may pose as much of a threat to vervet health as vice versa. / Department of Anthropology
25

The socioecology and conservation of the Samango monkey (Cercopithecus mitis erythrarchus) in Natal.

Lawes, Michael John. January 1990 (has links)
The samango monkey (Cercopithecus mitis erythrarchus) is the southern most representative of the polytypic mitis group. The samango is also the only truly arboreal guenon to have radiated as far as 30°S. At southern latitudes a greater seasonality of climate and an attendant seasonal shift in food availability is expected to restrict the foraging strategy of the arboreal guenon. In the absence of arboreal congenerics and few frugivorous bird and bat species, the samango experiences a level of competitive release at Cape Vidal not found in other equatorially located mitis populations. In this thesis I examine and contrast the diet and feeding behaviour of the mitis species group. In this way I illustrate the consequences of seasonality of food abundance and competitive release on the foraging strategy of the samango, and provide an explanation for the unique distribution of the samango monkey as the only arboreal guenon in southern Africa. Despite seasonality in climate and abundance of food resources, my data show that, in general, samango monkeys at Cape Vidal are not food limited. For this reason Cape Vidal samangos have large troop sizes (25+), use small home ranges (15 ha) and have the highest density (2.02 ind/ha) of any C. mitis population researched to date. Fruit forms an important part of the diet year-round and therefore, energy and carbohydrate are abundant. There is very little intra-group aggression for food, although interindividual distances are greatest when feeding. There are age-sex differences in the diet, and adult males eat more fruit while females eat more leaves than other age-sex classes. The most important aspect of the feeding strategy of the samango is concerned with obtaining adequate protein in the diet, and throughout the range of the mitis group, populations differ most in feeding strategies used to secure protein-rich foods, such as young leaves, flowers and invertebrates. In this respect seasonal nutrient (protein) availability, rather than seasonality of food abundance per se, is the most limiting component of the forest environment. Unlike equatorial populations of mitis that derive most of their protein from insects, samangos are unable to adopt a similar strategy. Insects were available to the monkeys, and then only in low numbers, in the wet summer season at Cape Vidal. Samango monkeys, therefore, make greater use of a wider variety of plant items for protein acquisition. During the wet summer months, insects, flowers and young leaves are used by samangos to obtain sufficient protein for important reproductive activities, such as lactation, and initial growth of the infant. During the drier winter months only mature leaves and small quantities of young leaves are available as protein resources, consequently samangos use more mature leaf in the diet than other C. mitis populations. Adaptations of the gut and specialized gut microflora permit this high degree of folivory in the diet (Bruorton and Perrin 1988) of the samango monkey. This is a characteristic that does not appear to be shared with other arboreal guenons. In so far as protein is essential for reproduction, folivory in c. mitis has been important in permitting this arboreal guenon species-group to radiate into southern latitudes where protein is more seasonally available. The ability of samango monkeys to eat large quantities of leaves at anyone time, accounts for their unique position as the only arboreal guenon species in southern Africa. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1990.
26

Zur Nosologie von im Leipziger Zoo gehaltenen Meerkatzen (Gattungen Cercopithecus, Erythrocebus, Miopithecus) Eine Analyse des Krankheitsgeschehens von 1955 bis 2006 unter Berücksichtigung von Immobilisation und Narkose

Schütte, Barbara 03 November 2008 (has links) (PDF)
Um Meerkatzen in zoologischen Gärten erfolgreich halten und nachzüchten zu können und um Menschen, die Kontakt zu den Tieren haben, vor Zoonosen zu schützen, ist es wichtig, einen guten Kenntnisstand über die bei diesen Tieren potenziell vorkommenden Krankheiten zu besitzen. In dieser Arbeit wird eine Übersicht über die in der Fachliteratur bei Meerkatzen beschriebenen Infektionen und Krankheiten gegeben und durch die veterinärmedizinischen Erfahrungen aus 51 Jahren Meerkatzenhaltung im Zoologischen Garten Leipzig ergänzt. Als Grundlage für die Analyse des Krankheitsgeschehens bei Meerkatzen im Zoologischen Garten Leipzig dienten Krankenblätter, Einträge in Visitebücher, Obduktionsprotokolle, Befunde von weiterführenden Untersuchungen und Narkoseprotokolle. Es wurden medizinische Daten von rund 150 Meerkatzen aus 17 verschiedenen Arten zusammengetragen und in Form von 387 Fallberichten ausgewertet und dargestellt. Dabei handelte es sich um 333 Krankheitsfälle und 54 Fälle des Zucht und Haltungsmanagements. Überdies wurden bakteriologische, virologische, mykologische und parasitologische Untersuchungen wie auch Angaben zu Narkosen nochmals gesondert erfasst und ausgewertet. Des Weiteren wurden im Rahmen der Arbeit hämatologische und klinisch-chemische Referenzwerte für Meerkatzen im Zoologischen Garten Leipzig erstellt. Am häufigsten kamen mit 37,2 % in der untersuchten Population Krankheiten der Verdauungsorgane vor, wobei es sich in den meisten Fällen um relativ harmlose Durchfallerkrankungen handelte. Weniger häufig traten traumatisch bedingte Krankheiten (13,2 %) auf, von denen mehr als die Hälfte der Fälle Bissverletzungen waren. Krankheiten der Atmungsorgane betrafen 12,9 % der Krankheitsfälle und Störungen der Fortpflanzungsfunktionen, zu denen auch neonatale Krankheiten gerechnet wurden, 10,2 %. 9,9 % der Krankheitsfälle wurden der Gruppe der unspezifischen Krankheiten zugeordnet, da es sich um Fälle mit unspezifischer Symptomatik handelte. Andere Krankheiten, wie solche der Haut und des Haarkleides (6,6 %), des Nervensystems (3 %), des Herz-Kreislauf-Systems (2,4 %), der Bewegungsorgane (2,1 %), des Harnapparates (0,9 %), der Sinnesorgane (0,6 %) sowie von Leber, Pankreas und Endokrinium (je 0,3 %), waren eher selten. Es wurden 69 Todesfälle gezählt. Die höchsten Tierverluste (15) waren im Zusammenhang mit Krankheiten der Atmungsorgane zu verzeichnen, wobei der Tuberkulose (8 Todesfälle) hier eine entscheidende Bedeutung zukam. In der Literatur bisher nicht beschriebene Infektionen und Krankheiten werden entsprechend ihrer Bedeutung herausgestellt. Es werden Empfehlungen zu verschiedenen, in der Analyse besonders aufgefallenen Aspekten der medizinischen Betreuung von Meerkatzen gegeben. Hierzu zählen z.B. das Management von Tuberkulose und Hepatitis A, die Vermeidung gehäuft auftretender Bissverletzungen durch Optimierung von Gruppenzusammensetzung und Haltungsbedingungen, eine mögliche Prophylaxe epileptiformer Anfälle bei Jungtieren durch Vitamin D3-Substitution und Uterusleiomyome als Ursache für Menstruationsbeschwerden. Außerdem werden Empfehlungen zur Immobilisation gegeben. Der praktizierende Tierarzt erhält somit einen Überblick über Infektionen und Krankheiten, die bei Meerkatzen vorkommen können, sowie deren Bedeutung.
27

Spatial and temporal patterns in resource dispersion and the structure of range use and co-existence in a social omnivore Chlorocebus Aethiops

Barrett, Alan Sean 11 1900 (has links)
The movements of two vervet monkey troops were studied to determine whether they optimize their rate of food intake in relation to seasonal energy availability. The effect of variation in habitat structure on the troops’ foraging strategies while utilizing temporally and spatially distributed resources was determined. Troop home range boundaries were delineated, the various plant communities and species utilised by the troops identified and classified, and variations in home range and vegetation structure were reported. The diets of the troops were determined and compared. Effects of coexistence on competition were assessed. Vervet food trees were randomly selected, marked and seasonal phenological data collected. Samples of food items constituting the two troops diets were collected for energy analysis. Using geostatistical interpolation techniques, monthly energy values were extrapolated onto home range grids for the two vervet monkey troops. Grids were stored as database files that were interrogated through GIS simulation models. Using the stochastic processes inherent in Markov chain theory, a series of non-returning random walks were simulated for comparison to original routes taken by the two troops. Results from comparisons of home range energy, day range lengths and areas, shortest route energy to actual route energy, time spent in high energy areas, and energy utilisation from actual and randomly generated routes indicated that the two troops optimize resource energy available to them by adopting flexible foraging strategies. In environments where temporal and spatial variations in habitat structure affect the distribution of resources, it is essential that animals develop optimal foraging strategies to survive. For the two troops investigated, foraging strategies fluctuate between being time minimizers in more heterogeneous environments where resources are abundant, and energy maximisers in homogeneous environments where resources are constrained by low diversity and seasonality. / Environmental Sciences (Department) / D.Litt et Phil (Environmental Management)
28

Behavioral traits in vervet monkeys : a longitudinal study of four successive birth cohorts

Desbiolles, Caroline. January 2007 (has links)
No description available.
29

The expression of neurofilament protein and mRNA levels in the lateral geniculate nucleus and area V1 of the developing and adult vervet monkey (Ceorcopithicus aethiops) /

Kogan, Cary. January 1999 (has links)
No description available.
30

An examination of social arousal and its implications for social congnition in the South African vervet monkey / Petra L. McDougall

McDougall, Petra L, University of Lethbridge. Faculty of Arts and Science January 2010 (has links)
Self-directed behaviours (SDB) were recorded as a behavioural indicator of arousal in free-ranging vervet monkeys (Chlorocebus aethiops) inhabiting the Klein Karoo of South Africa. Measurement of SDB allowed for changes in arousal to be correlated with particular social situations, potentially providing insight into how monkeys perceive their social world. The research presented here is divided into three core chapters demonstrating that 1) arousal is influenced to a greater extent by degree of association than by hierarchical rank, 2) that an individual‟s level of arousal is influenced by its neighbour‟s spatial location, and 3) that habituated animals that no longer perceive humans as a direct threat nevertheless continue to respond to their presence in other ways. Overall, SDB appears to be a useful, non-invasive, simple means of investigating social arousal and its use has elucidated several key findings regarding the perception of social space and social partners in vervet monkeys. / ix, 103 leaves ; 28 cm

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