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A study of geophagy in Formosan macaques, Macaca cyclopis, at Mt. Longevity, Taiwan.Chia, San-Ming 29 July 2002 (has links)
Soil in the Mt. Longevity, Taiwan, eaten by Formosan macaques, was analyzed to determine the possible stimulus or stimuli for geophagy. I attempted to test the mineral supplementation hypothesis and to document macaques using particle size. I studied macaques soil-eating behavior from July 2000 to April 2002 in the Mt. Longevity, Taiwan, and analyzed soil samples eaten and uneaten by Formosan macaque for physical-chemical properties and geochemistry in the study area. The results show that samples of soil eaten contained relatively high iron ( 3.6% ) and aluminum ( 16.0% ). However, the concentration of samarium was significantly lower in soil from samples eaten than in the random samples. No difference in concentration of the remaining fifteen elements ( magnesium¡Bcalcium¡B chromium¡Bmanganese¡Bcopper¡Barsenic¡Bstrontium¡Bbarium¡Blanthanum¡Bcerium¡Bneodymium¡Bytterbium¡Bphosphorous¡Bsulfate¡Bchlorides ) and Nitrate nitrogen was found between these two groups of soil samples. Geophagy occurred at a high rate of 0.31 monkey per hour with an elevated frequency in the reproduction season. The density of geophagy has been estimated as 1.6¡Ñ103 individuals per km2 . Frequency of male geophagy were recorded highest in September. Frequency of Females eating soil was recorded mainly between February and April. The ingested soils were significantly richer in clay than control soils. This study supports the hypothesis that mineral supplementation is a major factor for Formosan macaque engaging in geophagy.
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Investigations into the properties of mistletoe leaves, Phoradendron spp. (Viscaceae) and geophagic material consumed by Ateles geoffroyi (Atelidae) at sites within the Santa Rosa National Park, Costa RicaRostron, Lynda Ann January 2014 (has links)
This project arose because of the desire by the resident Ateles research observers, at Santa Rosa, to attempt to ascertain a function for what they deemed ‘uncharacteristic’ behaviours. The following were important considerations meriting further investigation. • Phoradendron (mistletoe) consumption by Ateles spp. appeared to be present only at Santa Rosa; • Mistletoe selection was considered deliberate, as mature host leaf (which was available) was not selected; • More than one mistletoe was available in the normal home range of the monkey, but selection was dominated by one mistletoe/host combination; • Consumption was of relatively small volumes; • There was an apparent seasonality to the use of mistletoe; • Consumption of mature, mistletoe leaf occurred at times when there was no shortage of suitable fruit; • Limitations of the Ateles spp. digestive system made exploitation of mature leaf potentially problematic; • The monkeys were also seen consuming geophageous material; on occasion, this closely followed mistletoe consumption; • There were no published reports of Ateles spp. geophagy in Central America and/or tropical dry forest habitat. The aim of the subsequent investigation was to determine if there was any beneficial function that could be attributed to the materials and so provide a link to a self-mediation hypothesis for mistletoe and/or geophagy or to relate the determined geophagy properties to the other published functional hypotheses for geophagy. The novel aspect of this project was the development of a specific ‘gastric model’ reflecting the differences between Ateles and human digestive systems. This modified model was used to investigate geophagic and Phoradendron samples. It was hoped that this approach would lead to the identification or constituents in the samples, which may have physiological significance. Samples of the two species of mistletoe identified were collected from three Phoradendron/host tree combinations. Samples were extracted using the simulated gastric conditions and the extracts analysed. Analytical ‘fingerprints’ of the gastric extracts of the two species were obtained together with the antimicrobial activities of the extracts. Species variation in Phoradendron constituents and antimicrobial activity was detected. The principal difference between the eaten and non-eaten Phoradendron species was identified using HPLC and LC-MS, as chlorogenic acid. Chlorogenic acid has antibacterial and antioxidant properties, stimulates the immune system and has activities related to regulation of blood sugar levels. Phoradendron consumption wass during the wet season, which may be a period of increased bacterial and parasite infection. It also coincides with a change in dietary fruits. The geophagic samples were taken from sites previously used by Ateles, together with ‘control’ sites found in the home range of the study group. Analysis of the physical properties and characteristics was undertaken to attempt to identify the mineral content material. Further analyses then investigated the behaviour of the material in relation to the commonly accepted hypotheses for geophagy. Where possible these were investigated using the simulated gastric conditions. The physical characteristics of the samples did not resemble the previously published reports for geophagic material used by humans or non-human primates. The results failed to detect the presence of montmorillonite and only a suggestion of the presence of kaolinite. The results do not suggest that it functions as an antacid, an anti-diarrhoeal or mineral supplement. An increase in antibacterial activity was seen when geophagic material and Phoradendron samples were incubated together. A putative hypothesis for the mechanism of Fe limitation was suggested by the physical properties of the geophagic material and the Fe chelating potential of the chemical constituents of the Phoradendron leaf.
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Geophagic practices and geophagic soil nematode content in Thabo Mofutsanyane District, South AfricaPerridge, Allison 12 1900 (has links)
Thesis (M. Tech.(Biomedical Technology)) - Central University of Technology, Free State, 2010 / Introduction: Geophagia, generally referred to as earth-eating, occurs in many countries of the world, including African countries such as South Africa. A need was identified to characterize human geophagic habits and the microbiological content of geophagic clayey soil, including the presence of potentially pathogenic nematodes (geohelminths), in South Africa.
Materials and methods: Questionnaires were developed to generate data on human geophagia and included demography, socio-economics, indigenous knowledge, business aspects, mining and hygiene practices of vendors/geophagists. A total of 52 soil samples (n = 52) were collected from the district of Thabo Mofutsanyane (Free State, South Africa), which comprised of vendor, topsoil, excavated and control soil sample groups. Nematode content were isolated using the Ammonium bicarbonate protocol, thereafter the nematodes were classified and population sizes determined for each sample. Soil colour classification was completed using the Munsell Soil Color Charts.
Results and discussion: The questionnaire revealed that geophagia in this region was practised mainly by women of child-bearing age because of the taste of the soil. Vendors sell geophagic clayey soil (known as mobu) collected from the mountain- and riversides for subsistence, generally costing one to two rand per bag. Hygiene and environmental conditions are considered when mining geophagic clayey soils. Whitish-perceived clayey soils are preferred by most of the geophagists. According to the Munsell Soil Color classification, Thabo Mofutsanyane geophagic soils ranged from brownish, to greyish, to yellowish in colour. Vendor soils were mostly greyish, while topsoils, excavated soils and control soils were mostly brownish. No human pathogenic nematode ova or larvae were isolated from any of the samples, however 34 nonpathogenic nematode taxa representing five trophic levels were identified. These included mainly herbivores, but also fungivores, bacteriovores, omnivores and predators. Taxon richness (number of taxa) greatly varied in the soil sample groups with vendor soil n = 9, topsoil n = 24, excavated soil n = 16 and control soil n = 14. Tylenchus sp., Criconemoides sphaerocephalus and Ditylenchus sp. were the only nematode taxa identified in all the different sample groups, with Tylenchus sp. notably more abundant overall. When the median nematode population sizes were compared between the geophagic soil samples, no significant difference (p ≥ 0.05) could be identified. In contrast, the median nematode population sizes for all samples differed significantly (p < 0.05) from the control soil sample group.
Conclusion: This study revealed that geophagia is probably not a vector for geohelminth infection in the district of Thabo Mofutsanyane, South Africa. However, the rich presence of non-pathogenic soil nematode communities in these brownish, greyish and yellowish geophagic soils may be useful as biological indicators of general soil health.
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Do barro ao bamburro : relações entre a paisagem e a distribuição local de mamíferos e aves no Pantanal, BrasilCoelho, Igor Pfeifer January 2016 (has links)
A relação entre a paisagem e a distribuição da ocorrência e abundância das espécies no espaço é uma das questões centrais em ecologia, com importantes aplicações diretas em tempos de intenso uso da terra e mudanças climáticas por atividades humanas. Contudo, para inferirmos sobre essas relações, temos que descrever a paisagem da forma mais próxima possível de como as espécies realmente a percebem. Uma paisagem pode ser descrita em diferentes níveis hierárquicos de organização do ambiente (e.g. quantidade de um mineral no solo, número de plantas em uma parcela, área de cobertura de floresta...), e cada nível pode ser descrito em diferentes escalas (resolução e extensão de descrição). Os níveis e escalas com maior poder de previsão da ocorrência/abundância de uma espécie são chamados de nível de efeito e escala (extensão) de efeito. Nesta tese, utilizo armadilhas fotográficas e modelos hierárquicos para avaliar relações entre a paisagem e espécies de mamíferos e aves. Meus objetivos são: (1) avaliar se existe relação entre nível e extensão de efeito para prever a abundância de espécies e a área de vida ou massa das mesmas; (2) investigar características do solo que possam ser determinantes da distribuição de mamíferos e aves que consumem solo (geofagia); e (3) a partir de ralações espécie-paisagem, estimar a distribuição da densidade de uma espécie, o veado-catingueiro, para diferentes datas. Não há suporte para que a área de vida ou a massa de uma espécie sejam relevantes para o nível ou extensão em que uma paisagem deva ser descrita a fim de prever a abundância de uma espécie. Isso implica na importância de se avaliar diferentes níveis e extensões de uma paisagem quando na busca por relações espécie-paisagem. Fatores locais, como a argila ou minerais do solo, podem ser importantes para algumas espécies. Descobri que o veado-mateiro e o caititu selecionam solos para consumo com base na quantidade e tipo de argila. O caititu também seleciona solos com base na concentração de microminerais, assim como a juriti-azul, a arara-azul-grande, o mutum, o aracuã e a pomba-galega. Uma descrição da paisagem em nível de composição do solo pode ser relevante para avaliar a distribuição destas e outras espécies. Relações espécie-paisagem podem ser usadas para prever a abundância de espécies no espaço. Estimei a densidade do veado-catingueiro em 1992 (2,07 ind/km2) e em 2011 (7,31 ind/km2), para uma região de pecuária extensiva no nordeste do Pantanal onde foi criada uma reserva em 1997. A densidade desta espécie aumentou 3,5 vezes entre 1992 e 2011, com o fim da pecuária no local. Investigações multinível e multiescala de relações espécie-paisagem ainda são incipientes, embora importantes aplicações destas relações já venham sendo feitas há décadas. / The relationship between the landscape and the distribution of species’ occurrence and abundance is one of the main questions in ecology, with important applications for the current period of intense land use and climate change. However, to infer about these relationships, we have to describe the landscape as closely as possible to how species actually realize it. We can describe landscapes at different hierarchical levels of the environment (e.g. mineral amount in soil, number of plants in a plot, forest cover area…), and each level can be described at different scales (resolution and extent). The best levels and scales to predict species’ occurrence/abundance are known as level of effect and scale (extent) of effect. In this PhD thesis, I use camera traps and hierarchical models to assess relationships between the landscape and mammals or birds. My goals are: (1) to evaluate possible relationships between the level and extent of effect to predict species’ abundance and species’ home range or mass; (2) to investigate soil features important to the distribution of mammals and birds engaged on geophagy (soil consumption); and (3) from species-landscape relations, to estimate the density of a species, the Gray Brocket in space for different dates. There is no support for species’ home range or mass as relevant traits related to the level and scale that a landscape should be described in order to predict species’ abundance. This highlight the importance of evaluating different levels and scales of a landscape when searching for species-landscape relationships. Local factors such as clay or minerals may be important for some species. I found that the Red Brocket and Collared Peccary select soils for consumption based on clay amount and type. The Collared Peccary also selects soil based on the concentration of trace minerals, as well as Blue Ground-dove, Hyacinth Macaw, Bare-faced Curassow, Chaco Chachalaca, and Pale-vented Pigeon. Describing the landscape at soil composition level may be important to evaluate the distribution of these and another species. Species-landscape relationships can be used to predict the abundance of species in space at different dates. I estimated the density of the Gray Brocket in 1992 (2.07 ind/km2) and 2011 (7.31 ind/km2), in a livestock region in northeastern Brazilian Pantanal where a reserve was established in 1997. Gray Brocket density increased 3.5 times between 1992 and 2011, after livestock ban. Multi-level and multi-scale approaches to investigate species-landscape relationships are still emerging, though important applications of such relationships have been done for decades.
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Do barro ao bamburro : relações entre a paisagem e a distribuição local de mamíferos e aves no Pantanal, BrasilCoelho, Igor Pfeifer January 2016 (has links)
A relação entre a paisagem e a distribuição da ocorrência e abundância das espécies no espaço é uma das questões centrais em ecologia, com importantes aplicações diretas em tempos de intenso uso da terra e mudanças climáticas por atividades humanas. Contudo, para inferirmos sobre essas relações, temos que descrever a paisagem da forma mais próxima possível de como as espécies realmente a percebem. Uma paisagem pode ser descrita em diferentes níveis hierárquicos de organização do ambiente (e.g. quantidade de um mineral no solo, número de plantas em uma parcela, área de cobertura de floresta...), e cada nível pode ser descrito em diferentes escalas (resolução e extensão de descrição). Os níveis e escalas com maior poder de previsão da ocorrência/abundância de uma espécie são chamados de nível de efeito e escala (extensão) de efeito. Nesta tese, utilizo armadilhas fotográficas e modelos hierárquicos para avaliar relações entre a paisagem e espécies de mamíferos e aves. Meus objetivos são: (1) avaliar se existe relação entre nível e extensão de efeito para prever a abundância de espécies e a área de vida ou massa das mesmas; (2) investigar características do solo que possam ser determinantes da distribuição de mamíferos e aves que consumem solo (geofagia); e (3) a partir de ralações espécie-paisagem, estimar a distribuição da densidade de uma espécie, o veado-catingueiro, para diferentes datas. Não há suporte para que a área de vida ou a massa de uma espécie sejam relevantes para o nível ou extensão em que uma paisagem deva ser descrita a fim de prever a abundância de uma espécie. Isso implica na importância de se avaliar diferentes níveis e extensões de uma paisagem quando na busca por relações espécie-paisagem. Fatores locais, como a argila ou minerais do solo, podem ser importantes para algumas espécies. Descobri que o veado-mateiro e o caititu selecionam solos para consumo com base na quantidade e tipo de argila. O caititu também seleciona solos com base na concentração de microminerais, assim como a juriti-azul, a arara-azul-grande, o mutum, o aracuã e a pomba-galega. Uma descrição da paisagem em nível de composição do solo pode ser relevante para avaliar a distribuição destas e outras espécies. Relações espécie-paisagem podem ser usadas para prever a abundância de espécies no espaço. Estimei a densidade do veado-catingueiro em 1992 (2,07 ind/km2) e em 2011 (7,31 ind/km2), para uma região de pecuária extensiva no nordeste do Pantanal onde foi criada uma reserva em 1997. A densidade desta espécie aumentou 3,5 vezes entre 1992 e 2011, com o fim da pecuária no local. Investigações multinível e multiescala de relações espécie-paisagem ainda são incipientes, embora importantes aplicações destas relações já venham sendo feitas há décadas. / The relationship between the landscape and the distribution of species’ occurrence and abundance is one of the main questions in ecology, with important applications for the current period of intense land use and climate change. However, to infer about these relationships, we have to describe the landscape as closely as possible to how species actually realize it. We can describe landscapes at different hierarchical levels of the environment (e.g. mineral amount in soil, number of plants in a plot, forest cover area…), and each level can be described at different scales (resolution and extent). The best levels and scales to predict species’ occurrence/abundance are known as level of effect and scale (extent) of effect. In this PhD thesis, I use camera traps and hierarchical models to assess relationships between the landscape and mammals or birds. My goals are: (1) to evaluate possible relationships between the level and extent of effect to predict species’ abundance and species’ home range or mass; (2) to investigate soil features important to the distribution of mammals and birds engaged on geophagy (soil consumption); and (3) from species-landscape relations, to estimate the density of a species, the Gray Brocket in space for different dates. There is no support for species’ home range or mass as relevant traits related to the level and scale that a landscape should be described in order to predict species’ abundance. This highlight the importance of evaluating different levels and scales of a landscape when searching for species-landscape relationships. Local factors such as clay or minerals may be important for some species. I found that the Red Brocket and Collared Peccary select soils for consumption based on clay amount and type. The Collared Peccary also selects soil based on the concentration of trace minerals, as well as Blue Ground-dove, Hyacinth Macaw, Bare-faced Curassow, Chaco Chachalaca, and Pale-vented Pigeon. Describing the landscape at soil composition level may be important to evaluate the distribution of these and another species. Species-landscape relationships can be used to predict the abundance of species in space at different dates. I estimated the density of the Gray Brocket in 1992 (2.07 ind/km2) and 2011 (7.31 ind/km2), in a livestock region in northeastern Brazilian Pantanal where a reserve was established in 1997. Gray Brocket density increased 3.5 times between 1992 and 2011, after livestock ban. Multi-level and multi-scale approaches to investigate species-landscape relationships are still emerging, though important applications of such relationships have been done for decades.
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Do barro ao bamburro : relações entre a paisagem e a distribuição local de mamíferos e aves no Pantanal, BrasilCoelho, Igor Pfeifer January 2016 (has links)
A relação entre a paisagem e a distribuição da ocorrência e abundância das espécies no espaço é uma das questões centrais em ecologia, com importantes aplicações diretas em tempos de intenso uso da terra e mudanças climáticas por atividades humanas. Contudo, para inferirmos sobre essas relações, temos que descrever a paisagem da forma mais próxima possível de como as espécies realmente a percebem. Uma paisagem pode ser descrita em diferentes níveis hierárquicos de organização do ambiente (e.g. quantidade de um mineral no solo, número de plantas em uma parcela, área de cobertura de floresta...), e cada nível pode ser descrito em diferentes escalas (resolução e extensão de descrição). Os níveis e escalas com maior poder de previsão da ocorrência/abundância de uma espécie são chamados de nível de efeito e escala (extensão) de efeito. Nesta tese, utilizo armadilhas fotográficas e modelos hierárquicos para avaliar relações entre a paisagem e espécies de mamíferos e aves. Meus objetivos são: (1) avaliar se existe relação entre nível e extensão de efeito para prever a abundância de espécies e a área de vida ou massa das mesmas; (2) investigar características do solo que possam ser determinantes da distribuição de mamíferos e aves que consumem solo (geofagia); e (3) a partir de ralações espécie-paisagem, estimar a distribuição da densidade de uma espécie, o veado-catingueiro, para diferentes datas. Não há suporte para que a área de vida ou a massa de uma espécie sejam relevantes para o nível ou extensão em que uma paisagem deva ser descrita a fim de prever a abundância de uma espécie. Isso implica na importância de se avaliar diferentes níveis e extensões de uma paisagem quando na busca por relações espécie-paisagem. Fatores locais, como a argila ou minerais do solo, podem ser importantes para algumas espécies. Descobri que o veado-mateiro e o caititu selecionam solos para consumo com base na quantidade e tipo de argila. O caititu também seleciona solos com base na concentração de microminerais, assim como a juriti-azul, a arara-azul-grande, o mutum, o aracuã e a pomba-galega. Uma descrição da paisagem em nível de composição do solo pode ser relevante para avaliar a distribuição destas e outras espécies. Relações espécie-paisagem podem ser usadas para prever a abundância de espécies no espaço. Estimei a densidade do veado-catingueiro em 1992 (2,07 ind/km2) e em 2011 (7,31 ind/km2), para uma região de pecuária extensiva no nordeste do Pantanal onde foi criada uma reserva em 1997. A densidade desta espécie aumentou 3,5 vezes entre 1992 e 2011, com o fim da pecuária no local. Investigações multinível e multiescala de relações espécie-paisagem ainda são incipientes, embora importantes aplicações destas relações já venham sendo feitas há décadas. / The relationship between the landscape and the distribution of species’ occurrence and abundance is one of the main questions in ecology, with important applications for the current period of intense land use and climate change. However, to infer about these relationships, we have to describe the landscape as closely as possible to how species actually realize it. We can describe landscapes at different hierarchical levels of the environment (e.g. mineral amount in soil, number of plants in a plot, forest cover area…), and each level can be described at different scales (resolution and extent). The best levels and scales to predict species’ occurrence/abundance are known as level of effect and scale (extent) of effect. In this PhD thesis, I use camera traps and hierarchical models to assess relationships between the landscape and mammals or birds. My goals are: (1) to evaluate possible relationships between the level and extent of effect to predict species’ abundance and species’ home range or mass; (2) to investigate soil features important to the distribution of mammals and birds engaged on geophagy (soil consumption); and (3) from species-landscape relations, to estimate the density of a species, the Gray Brocket in space for different dates. There is no support for species’ home range or mass as relevant traits related to the level and scale that a landscape should be described in order to predict species’ abundance. This highlight the importance of evaluating different levels and scales of a landscape when searching for species-landscape relationships. Local factors such as clay or minerals may be important for some species. I found that the Red Brocket and Collared Peccary select soils for consumption based on clay amount and type. The Collared Peccary also selects soil based on the concentration of trace minerals, as well as Blue Ground-dove, Hyacinth Macaw, Bare-faced Curassow, Chaco Chachalaca, and Pale-vented Pigeon. Describing the landscape at soil composition level may be important to evaluate the distribution of these and another species. Species-landscape relationships can be used to predict the abundance of species in space at different dates. I estimated the density of the Gray Brocket in 1992 (2.07 ind/km2) and 2011 (7.31 ind/km2), in a livestock region in northeastern Brazilian Pantanal where a reserve was established in 1997. Gray Brocket density increased 3.5 times between 1992 and 2011, after livestock ban. Multi-level and multi-scale approaches to investigate species-landscape relationships are still emerging, though important applications of such relationships have been done for decades.
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A qualitative study of selected micro-organisms in geophagic soil from Qwa-QwaSmit, Nellie Jacoba January 2011 (has links)
Thesis (M. Tech.(Biomedical Technology)) - Central University of technology, Free State, 2011 / The existence of geophagia from as early as 460 BC up to now, makes it relevant to investigate all aspects related to geophagia. Geophagia is a direct route for potential transmission of pathogens to the human host, through the ingestion of soil. Soil-borne diseases in humans are causing growing concern as sewage disposal, which involve sewage sludge and waste water drainage from these plants, is on the increase. It is estimated that approximately seven million tons of sewage sludge is produced annually and that 54% of this sewage sludge is introduced into soil. Data on enteric infection in humans caused by contamination from soil is limited and need further investigation. The aim of the study was, therefore, to collect information on the microbiological presence in geophagic soil in the Qwa-Qwa district. Objectives included the collecting of information regarding various sampling sites in the Qwa-Qwa district and also soil samples sold by vendors, investigation of the prevalence of known human pathogenic bacteria and fungi in geophagic soil, investigating the culturability of Salmonella enteritidis in geophagic soil in comparison with the viability of these organisms in soil for long periods of time, investigating potential antimicrobial activity of geophagic soil, as some of the geophagists are convinced that the geophagic soils have medicinal properties, and to determine the microbial diversity of geophagic soils, which can not be accomplished by conventional microbial culturing methods.
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The investigation of iron and mineral deficiency associated with the practice of geophagiaVan Wyk, Mari January 1900 (has links)
Thesis (M. Tech. (Biomedical Technology)) -- Central University of technology, Free State, [2013] / Introduction: Geophagia, a subcategory of pica, is the practice of persistently and deliberately eating earthy or soil like substances. A definite cause for the practice of geophagia is yet to be established, but some theories claim that the soil holds nutritional value to the geophagist.
Method: Geophagic woman in the QwaQwa area between the ages of 18 and 45 years were identified by means of a questionnaire. A test group, consisting of 48 women in the habit of consuming soil, and a control group, consisting of 35 non geophagous women, were identified. Subjects in the control group were chosen from the same household or in the same area as the test subjects. On each subject, of both the test group and the control group, the following tests were done: total serum iron, transferrin, ferritin, calcium, magnesium, phosphate and albumin. The results obtained were statistically analysed and compared. Biochemical results were compared with haematology results obtained by another researcher, using the same test group and control group subjects.
Results: In the test group, 75% of the individuals had results indicative of iron deficiency, compared to only 26% in the control group. The haematology results also indicate anaemia in the test group, most probably brought on by iron deficiency. There was no significant difference in mineral results between the test- and control group. Thus no association could be established between soil consumption and mineral status. Conclusion: In relation to non-geophagous women, people who consume soil have a tendency toward iron deficiency. It is impossible to ascertain whether the iron deficiency caused the craving for soil, or whether the consumption of soil caused the iron deficiency. No definite association could be made between soil consumption and mineral status.
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Association between geophagia and haematological parameters of iron deficiency anaemia amongst geophagic Qwa-Qwa womenRaphuthing, Manneheng. Violet. January 1900 (has links)
Thesis (M. Tech. (Biomedical Technology)) -- Central University of Technology, Free State, [2014] / Pica is the habitual eating of non-food substances by humans and animals. It has
different subgroups and these are defined by the ingested substance. Moreover,
geophagia is a type of pica that refers to the consistent eating of mostly earth and
earth-like substances such as clay and soil. It is observed in both sexes, all age
groups and in different ethnic groups around the world. There are many reasons
people give for the practice of geophagia, such as culture, hunger and health being
the most prominent. Geophagic materials differ in texture, colour and taste. Soil
colour classification according to the Munsell soil classification, which uses hues,
values and chroma, sometimes differ with the soil colour being noticeable with the
naked eye. However, geophagic clays from Qwa-Qwa are white and contain kaoline.
Geophagic materials are believed to augment mineral deficiency, especially
magnesium, calcium and iron. Geophagia is practised mainly by females, especially
during their child bearing years. Females are more prone to iron deficiency anaemia
due to their monthly menstruation cycle. Iron deficiency is the most common cause
of anaemia and is classified as hypochromic microcytic anaemia (HMA). This study
focused on the health aspect of geophagia. The research question seeks to explore
whether there is an association between geophagia and the haematological
parameters of iron deficiency anaemia. Geophagia seems to be linked with the
occurrence of anaemia, but not iron deficiency anaemia, although it is implied. It is
not known if the practice of geophagia causes iron deficiency anaemia or if it is
because of iron deficiency anaemia that people practise geophagia. A pilot study
was done in 2007, and the results of that study prompted that this study be
performed on a bigger scale.
The lack of information regarding the quantity, frequency and type of geophagic
material consumed the impact of geophagia on haematological parameters and the
iron status of the geophagists made it important that the primary existence of the
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relationship be investigated. In addition, research to establish whether there is a
relationship between geophagia and haematological parameters of iron deficiency
anaemia, has not been undertaken in South Africa, especially on non-pregnant
women. Geophagia seems to always be accompanied by the subject of iron
deficiency anaemia and especially its prevalence in females. The bigger geophagia
project was therefore an ideal opportunity to do a specific survey on geophagic
women.
This was a cross-sectional study, consisting of 36 control women and 47 geophagic
women, aged between 18-45 years. The participants completed a questionnaire to
determine the geophagic practices, which included the colour of the clay, how
frequent the clay was consumed, how much was consumed and for how long it has
been consumed. Nutritional status was assessed using a food frequency
questionnaire. Blood was drawn to assess the haematological and iron status of the
participants.
The participants of the study were within the required age range, with no significant
difference between the groups (p-value=0.7914). The most consumed colour of clay
was white and white clay contains kaoline, which has the ability to absorb iron in the
duodenum. The majority of the participants consumed 40 grams of clay on a daily
basis, with most of the participants having done so for 5 years. Diet was ruled out as
the cause of iron deficiency.
The haematological parameters indicated that the geophagic group (43%) were
inclined to have hypochromic microcytic anaemia, while a small percentage of
control groups (8%) had HMA; this was revealed by the red cell parameters and red
cell indices. In addition, the odds ratio for the haematological results revealed that
the probability of a geophagic person developing anaemia was two times greater
than that of a non-geophagic person. Platelet results partially ruled out bleeding as
a cause of anaemia. The median red cell distribution width indicated that the
iv
geophagic group was inclined to have anisocytosis. The geophagic group was
found to have iron deficiency (75%), whilst the control group had a small
percentage with iron deficiency (22%), which was validated by the serum ferritin,
serum iron and saturated transferrin (chemical analysis). The odds ratio revealed
that the probability of a geophagic person being iron deficient is 3 times greater
than that of a non-geophagic person. The strongest association is seen with iron
study findings, because being iron deficient showed the highest odd ratio than the
association with red cell morphology and even haemoglobin. Thus, participants
were more iron deficient than suffering from iron deficiency anaemia.
Inflammatory and parasitic indicators proved that inflammation and infection was
uncommon in both groups, and therefore did not compromise the credibility of the
iron study results. Inflammatory indicators (white blood cells, erythrocyte
sedimentation rate and C-reactive protein) ruled out inflammation, whilst eosinophil
count showed no indication of parasitic infection for both geophagic and control
groups.
To conclude, the study found that an association exists between geophagia and
haematological parameters of iron deficiency anaemia amongst geophagic women
in Qwa-Qwa, in that geophagic material contributes to iron deficiency anaemia.
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