HEINZEN, Eduardo Luiz. Variáveis nutricionais e fisiológicas de ovinos da raça Morada Nova de diferentes classes sexuais submetidos à restrição alimentar. 2016. 50 f. : Dissertação (Mestrado) - Universidade Federal do Ceará, Centro de Ciências, Departamento de Zootecnia, Programa de Pós-Graduação em Zootecnia. Fortaleza-CE, 2016. / Submitted by Eric Santiago (erichhcl@gmail.com) on 2016-08-03T13:37:27Z No. of bitstreams: 1 2016_dis_elheinzen.pdf: 1285825 bytes, checksum: 32955795d549452fb81768336e0dfffc (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-03T13:51:24Z (GMT) No. of bitstreams: 1 2016_dis_elheinzen.pdf: 1285825 bytes, checksum: 32955795d549452fb81768336e0dfffc (MD5) / Made available in DSpace on 2016-08-03T13:51:24Z (GMT). No. of bitstreams: 1 2016_dis_elheinzen.pdf: 1285825 bytes, checksum: 32955795d549452fb81768336e0dfffc (MD5) Previous issue date: 2016 / This study was accomplished with the objective of determining the effects of sexual class and feed restriction on nutrient intake, digestibility, purine derivatives, nitrogen balance, feeding behavior and physiological parameters in hair sheep Morada Nova. Thirty-five animals (11 intact males, 12 castrated and 12 females) with an initial average weight of 14.5 ± 0,89kg were used in a completely randomized design in a 3x3 factorial design with three sexual classes (intact males, castrated and females) and three levels of feed restriction (ad libitum, 30 and 60%). Sexual class and feed restriction influenced (P<0.05) the intake of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber corrected for ash and protein (NDFap), total carbohydrates (TC), non-fibrous carbohydrates (NFC), total digestible nutrients (TDN) and metabolied energy (ME) and the balance of nitrogen compounds. The digestibility coefficient of DM, CP and EE were influenced (P<0.05) by feed restriction, however there was no effect (P>0.05) the sexual class on the digestibility coefficients of CP, EE and NFC. There was interaction between sexual class and feed restriction (P<0.05) in digestibility of OM, NDFap and CT. Eating times (ET) and rumination times (RUT) were affected by feed restriction (P<0.05), however they were not affected by sexual class (P>0.05). The urinary volume, excretions of creatinine, allantoin, xanthine and hypoxanthine, absorption of purine derivatives (absPD), total purine derivatives (PD) and microbial protein synthesis (micCP) were not influenced (P>0.05) by sexual class. Urine output, creatinine excretion, xanthine and hypoxanthine were not influenced by feed restriction (P>0.05), however, this factor influenced the excretion of allantoin, uric acid, absPD and PD. Physiological parameters, surficial temperature (ST) on the left of pectoral region and rectal temperature (RT), were not affected by sexual class (P>0.05). Feed restriction and the period of collect of physiological variables influenced (P<0.05) ST the left side, chest and RT. There was interaction (P<0.05) between sexual class and feed restriction ST to the right side. Intake and digestibility of nutrients are influenced by more severe dietary restrictions. Sexual class does not influence the excretion of purine derivatives and microbial protein synthesis. Feed restriction reduces heat losses by body surface of lambs. / Este estudo foi realizado com o objetivo de determinar os efeitos da classe sexual e restrição alimentar sobre o consumo de nutrientes, digestibilidade, derivados de purina, balanço de nitrogênio, comportamento ingestivo e parâmetros fisiológicos de cordeiros da raça Morada Nova. Trinta e cinco animais (11 machos inteiros, 12 castrados e 12 fêmeas), com peso médio inicial de 14,5 ± 0,89kg, foram usados em delineamento inteiramente casualizado, em esquema fatorial 3x3, sendo três classes sexuais (machos inteiros, castrados e fêmeas) e três níveis de restrição alimentar (ad libitum, 30 e 60%). A classe sexual e a restrição alimentar influenciaram (P<0,05) o consumo de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), extrato etéreo (EE), fibra em detergente neutro corrigida para cinzas e proteína (FDNcp), carboidratos totais (CT), carboidratos não fibrosos (CNF), nutrientes digestíveis totais (NDT) e de energia metabolizável (EM) e o balanço dos compostos nitrogenados. O coeficiente de digestibilidade da MS, PB e EE foram influenciados (P<0,05) pela restrição alimentar, no entanto, não houve efeito (P>0,05) da classe sexual sobre os coeficientes de digestibilidade da PB, EE e CNF. Houve interação entre a classe sexual e a restrição alimentar (P<0,05) na digestibilidade da MO, FDNcp e CT. Os tempos de alimentação (TAL) e ruminação (TRU) foram influenciados pela restrição alimentar (P<0,05), no entanto, não foram influenciados pela classe sexual (P>0,05). O volume urinário, excreções de creatinina, alantoína, xantina e hipoxantina, absorção de derivados de purina (absDP), derivados de purinas totais (DP) e síntese de proteína microbiana (PBmic) não foram influenciados (P>0,05) pela classe sexual. Volume urinário, excreções de creatinina, xantina e hipoxantina não foram influenciados pela restrição alimentar (P>0,05), no entanto, este fator influenciou as excreções de alantoína, ácido úrico, absDP e DP. Os parâmetros fisiológicos temperatura superficial (TS) do lado esquerdo, região peitoral e temperatura retal (TR) não foram influenciados pela classe sexual (P>0,05). A restrição alimentar e o período de coleta das variáveis fisiológicas influenciaram (P<0,05) a TS do lado esquerdo, peito e TR. Houve interação (P<0,05) entre classe sexual e restrição alimentar para TS do lado direito. Consumo e digestibilidade de nutrientes são influenciados por restrições alimentares mais severas. Classe sexual não influencia a excreção de derivados de purina e síntese de proteína microbiana. A restrição alimentar diminui as perdas de calor pela superfície corporal de cordeiros.

Forage of beta-carotene-fortified orange-fleshed sweet potato is essential for alleviation cattle malnutrition. The study aims were to determine effects of supplementing sweet potato (SP) roots and sun dried forage on degradation of dietary legumes, intake and milk yield in dairy cattle. Mature SP roots were oven dried and forage vines and leaves (V&L) sun dried. Lactating dairy were supplied meals with total mixed ration (TMR) constituting varying levels of sweet potato forage and concentrate. The SP flour was rapidly and completely degraded In Sacco while degradability of V&L was comparable to that of Lucerne hay. Rumen degradation of Lucerne was reduced when the legume was incubated proximal to SP. Substitution of TMR with fresh SP forage and flour meal increased degradability of diets. Glucose post-feeding was increased (P<0.05) by SP roots but no change in milk yield. Orange-fleshed SP forage is recommended for improving energy supply in lactating cow diets / Agriculture and  Animal Health / M. Sc. (Agriculture)

Resumo: O objetivo deste estudo foi rastrear a ocorrência de fatores de risco da síndrome metabólica em adolescentes eutróficos e com excesso de peso em dois momentos transversais, com intervalo de seis meses. A amostra foi constituída por 64 adolescentes divididos em quatro grupos: meninos eutróficos e com excesso de peso e meninas eutróficas e com excesso de peso. As variáveis investigadas foram: peso, estatura, circunferência da cintura, percentual de gordura corporal, pressão arterial, colesterol total, LDL-colesterol, HDLcolesterol , triglicerídeos, glicose, ingestão de nutrientes, número de passos diário e tempo gasto com hábitos sedentários (assistir televisão, uso de computador e videogames). A média de idade foi de 11,4 ±0,3 anos para os meninos e 11,5 ±0,3 anos para as meninas. Foi diagnosticado um caso de síndrome metabólica, mas a presença de fatores de risco foi constatada nas duas avaliações. Entre os adolescentes com excesso de peso, 56% dos meninos e 31% das meninas apresentaram obesidade abdominal na primeira avaliação e as mesmas proporções foram observadas no segundo momento. Houve aumento da incidência da proporção de adolescentes com baixa concentração de HDLcolesterol nos grupos eutróficos e com excesso de peso. Entre os adolescentes eutróficos, na segunda avaliação 44% dos meninos e 69% das meninas apresentaram HDL-colesterol inferior a 40 mg/dL. No grupo com excesso de peso, 69% dos meninos e 63% das meninas apresentaram tal condição. Houve redução significativa de HDL-colesterol acompanhada de aumento de triglicerídeos, dois parâmetros críticos no desenvolvimento da síndrome metabólica. Além disso, foi detectada correlação inversa e significativa entre triglicerídeos e HDL-colesterol nas duas avaliações. Entre os adolescentes com excesso de peso, houve aumento, em ambos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present study was aimed to track risk factors of metabolic syndrome in eutrophic and overweight adolescents in two time periods, with a time interval of six months between the two periods. The sample was composed of 64 adolescents divided into four groups: eutrophic boys, overweight boys, eutrophic girls and overweight girls. The assessed variables were: weight, height, waist circumference, body fat percentage, arterial blood pressure, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, glucose, nutrient intake, number of daily steps and hours of sedentary behavior (watching TV, playing on the computer or videogames). The average age of the boys was 11.4 ±0.3 years and of the girls was 11.5 ±0.3 years. One case of metabolic syndrome was diagnosed, but the presence of risk factors was detected in both assessments. Among overweight adolescents, 56% of the boys and 31% of the girls had abdominal obesity in the first assessment and the same percentage was found in the second assessment. There was an increase in the percentage of adolescents with low HDL-cholesterol concentrations in the eutrophic and overweight groups. Among the eutrophic adolescents, in the second assessment, 44% of the boys and 69% of the girls had HDL-cholesterol lower than 40 mg/dL. In the overweight group, 69% of the boys and 63% of the girls had this condition. There was a significant reduction in HDL-cholesterol followed by an increase in the triglycerides, two critical parameters in the development of the metabolic syndrome. Besides, an inverse and significant correlation between triglycerides and HDL-cholesterol was detected in both assessments. Among overweight adolescents there was an increase, in both sexes, in the number of adolescents with the two risk factors (boys: from 12% to 44%; - girls: from 6% to 25%), due... (Complete abstract click electronic access below) / Orientador: Thaïs Borges César / Coorientador: João Bosco Faria / Banca: Ellen Cristini Freitas Araújo / Banca: Marina Vieira da Silva / Banca: Anderson Marlieri Navarro / Banca: Maria Rita Marques de Oliveira / Doutor

nÃo hà / Este estudo foi realizado com o objetivo de determinar os efeitos da classe sexual e restriÃÃo alimentar sobre o consumo de nutrientes, digestibilidade, derivados de purina, balanÃo de nitrogÃnio, comportamento ingestivo e parÃmetros fisiolÃgicos de cordeiros da raÃa Morada Nova. Trinta e cinco animais (11 machos inteiros, 12 castrados e 12 fÃmeas), com peso mÃdio inicial de 14,5  0,89kg, foram usados em delineamento inteiramente casualizado, em esquema fatorial 3x3, sendo trÃs classes sexuais (machos inteiros, castrados e fÃmeas) e trÃs nÃveis de restriÃÃo alimentar (ad libitum, 30 e 60%). A classe sexual e a restriÃÃo alimentar influenciaram (P<0,05) o consumo de matÃria seca (MS), matÃria orgÃnica (MO), proteÃna bruta (PB), extrato etÃreo (EE), fibra em detergente neutro corrigida para cinzas e proteÃna (FDNcp), carboidratos totais (CT), carboidratos nÃo fibrosos (CNF), nutrientes digestÃveis totais (NDT) e de energia metabolizÃvel (EM) e o balanÃo dos compostos nitrogenados. O coeficiente de digestibilidade da MS, PB e EE foram influenciados (P<0,05) pela restriÃÃo alimentar, no entanto, nÃo houve efeito (P>0,05) da classe sexual sobre os coeficientes de digestibilidade da PB, EE e CNF. Houve interaÃÃo entre a classe sexual e a restriÃÃo alimentar (P<0,05) na digestibilidade da MO, FDNcp e CT. Os tempos de alimentaÃÃo (TAL) e ruminaÃÃo (TRU) foram influenciados pela restriÃÃo alimentar (P<0,05), no entanto, nÃo foram influenciados pela classe sexual (P>0,05). O volume urinÃrio, excreÃÃes de creatinina, alantoÃna, xantina e hipoxantina, absorÃÃo de derivados de purina (absDP), derivados de purinas totais (DP) e sÃntese de proteÃna microbiana (PBmic) nÃo foram influenciados (P>0,05) pela classe sexual. Volume urinÃrio, excreÃÃes de creatinina, xantina e hipoxantina nÃo foram influenciados pela restriÃÃo alimentar (P>0,05), no entanto, este fator influenciou as excreÃÃes de alantoÃna, Ãcido Ãrico, absDP e DP. Os parÃmetros fisiolÃgicos temperatura superficial (TS) do lado esquerdo, regiÃo peitoral e temperatura retal (TR) nÃo foram influenciados pela classe sexual (P>0,05). A restriÃÃo alimentar e o perÃodo de coleta das variÃveis fisiolÃgicas influenciaram (P<0,05) a TS do lado esquerdo, peito e TR. Houve interaÃÃo (P<0,05) entre classe sexual e restriÃÃo alimentar para TS do lado direito. Consumo e digestibilidade de nutrientes sÃo influenciados por restriÃÃes alimentares mais severas. Classe sexual nÃo influencia a excreÃÃo de derivados de purina e sÃntese de proteÃna microbiana. A restriÃÃo alimentar diminui as perdas de calor pela superfÃcie corporal de cordeiros. / This study was accomplished with the objective of determining the effects of sexual class and feed restriction on nutrient intake, digestibility, purine derivatives, nitrogen balance, feeding behavior and physiological parameters in hair sheep Morada Nova. Thirty-five animals (11 intact males, 12 castrated and 12 females) with an initial average weight of 14.5  0,89kg were used in a completely randomized design in a 3x3 factorial design with three sexual classes (intact males, castrated and females) and three levels of feed restriction (ad libitum, 30 and 60%). Sexual class and feed restriction influenced (P<0.05) the intake of dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber corrected for ash and protein (NDFap), total carbohydrates (TC), non-fibrous carbohydrates (NFC), total digestible nutrients (TDN) and metabolied energy (ME) and the balance of nitrogen compounds. The digestibility coefficient of DM, CP and EE were influenced (P<0.05) by feed restriction, however there was no effect (P>0.05) the sexual class on the digestibility coefficients of CP, EE and NFC. There was interaction between sexual class and feed restriction (P<0.05) in digestibility of OM, NDFap and CT. Eating times (ET) and rumination times (RUT) were affected by feed restriction (P<0.05), however they were not affected by sexual class (P>0.05). The urinary volume, excretions of creatinine, allantoin, xanthine and hypoxanthine, absorption of purine derivatives (absPD), total purine derivatives (PD) and microbial protein synthesis (micCP) were not influenced (P>0.05) by sexual class. Urine output, creatinine excretion, xanthine and hypoxanthine were not influenced by feed restriction (P>0.05), however, this factor influenced the excretion of allantoin, uric acid, absPD and PD. Physiological parameters, surficial temperature (ST) on the left of pectoral region and rectal temperature (RT), were not affected by sexual class (P>0.05). Feed restriction and the period of collect of physiological variables influenced (P<0.05) ST the left side, chest and RT. There was interaction (P<0.05) between sexual class and feed restriction ST to the right side. Intake and digestibility of nutrients are influenced by more severe dietary restrictions. Sexual class does not influence the excretion of purine derivatives and microbial protein synthesis. Feed restriction reduces heat losses by body surface of lambs.

Submitted by (edna.saturno@ufrpe.br) on 2017-05-17T14:02:54Z No. of bitstreams: 1 Maria Josilaine Matos dos Santos.pdf: 609545 bytes, checksum: 6c7d8659c798aee4fe33d56cf53317d8 (MD5) / Made available in DSpace on 2017-05-17T14:02:54Z (GMT). No. of bitstreams: 1 Maria Josilaine Matos dos Santos.pdf: 609545 bytes, checksum: 6c7d8659c798aee4fe33d56cf53317d8 (MD5) Previous issue date: 2011-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The experiment was conducted to evaluate the effects of inclusion of cassava instead of maize as feed for dairy goats of Saanen. The results were discussed in two chapters, the first consisting of the nutrient consumption, production, composition and physical characteristics of milk and the second digestibility and ingestive behavior of animals. Five lactating goats were used with an average production of 2 kg of milk per day allotted to a 5x5 Latin square design with five levels of inclusion of cassava (0, 10, 20, 30 and 40%) replacing corn. The dry matter intake in grams (g/day) in relation to body weight (%BW) and gram metabolic weight showed a quadratic behavior as a function of inclusion levels of cassava instead of maize grits. The intake of nutrients followed the behavior of dry matter intake. NDF intake, expressed in kilograms, depending on body weight and metabolic weight decreased linearly and non-fibrous carbohydrates linear increase. The replacement of cracked corn by cassava production did not affect kg of milk and milk yield corrected for 3.5% fat. The fat and total solids of milk in kg and percentage were not affected by inclusion levels of cassava instead of maize. The protein showed a linear increased and lactose quadratic effect. The physical characteristics of pH, temperature and density were not affected by inclusion levels of cassava instead of maize. The apparent digestibility of DM, CP, OM, TC was not affected by the replacement levels of ground corn for cassava. The apparent digestibility of the NDF fraction decreased linearly while that of CNF increased linearly with the increase of cassava in diets. Feeding behavior in all studied variables was not influenced by the inclusion of zest in place of corn. In dairy goats with produce of 2,0kg of milk per day, the corn grain can be completely replaced by cassava, resulting in increased nutrient intake above 30% inclusion, without changing the physical characteristics and production of milk, positively just changes the protein and lactose. The replacement of cracked corn by cassava did not affect the digestibility and chewing behavior of lactating goats. However, chalking and non-fiber carbohydrate of cassava are characteristics that should be considered. / O experimento foi conduzido com o objetivo de avaliar os efeitos da inclusão da raspa de mandioca em substituição ao milho na alimentação de cabras leiteiras de raça Saanen. Os resultados foram discutidos em dois capítulos: o primeiro tratou do consumo de nutrientes, produção, composição e características físicas do leite, e o segundo da digestibilidade de nutrientes e do comportamento ingestivo dos animais. Foram utilizadas cinco cabras lactantes com produção média de 2kg de leite/dia, distribuídas em um quadrado latino 5x5, com cinco níveis de inclusão de raspa de mandioca (0, 10, 20, 30 e 40%) em substituição ao milho. O consumo de matéria seca em grama (g/dia), em relação ao peso vivo (%PV) e grama por peso metabólico apresentou comportamento quadrático em função dos níveis de inclusão da raspa de mandioca em substituição do milho triturado. O consumo dos nutrientes seguiu o comportamento do consumo de matéria seca. O consumo de FDN, expresso em quilograma, em função peso vivo e peso metabólico, apresentou comportamento linear decrescente e carboidratos não fibrosos linear crescente. A substituição do milho triturado pela raspa de mandioca não influenciou a produção de leite em kg e produção de leite corrigido para 3,5% de gordura. A gordura e sólidos totais do leite em percentuais e em kg não foram influenciados pelos níveis de inclusão de raspa de mandioca em substituição ao milho. A proteína apresentou efeito linear crescente e lactose efeito quadrático. As características físicas pH, densidade e temperatura não foram influenciadas pelos níveis de inclusão da raspa de mandioca em substituição ao milho. A digestibilidade aparente da MS, PB, MO, CHOT não foi influenciada pelos níveis de substituição do milho triturado por raspa de mandioca. A digestibilidade aparente da fração FDN diminuiu linearmente enquanto que a dos CNF aumentou linearmente em função do aumento de raspa de mandioca nas dietas experimentais. O comportamento ingestivo, em todas as variáveis estudadas, não teve influência da inclusão da raspa em substituição ao do milho. Em cabras leiteiras com produção de 2,0kg de leite/dia o milho triturado pode ser substituído pela raspa de mandioca em níveis superiores de 30% até a completa substituição, com aumento de consumo de nutrientes, sem alterar a produção e características físicas de leite, apenas altera positivamente os teores de proteína e lactose. Não interfere na digestibilidade, assim como no comportamento ingestivo de cabas em lactação.

Background: People in Cameroon are experiencing a dietary transition characterized by changing from traditional food habits to increased intake of highly processed sweet and fatty food. The rapid change in food pattern combined with an increased sedentary lifestyle has resulted in a rather high prevalence of obesity, hypertension, cardiovascular diseases and type 2 diabetes. Nutritional intake is important during adolescence for growth spurt, health, cognitive development and performance in school. Objective: The aim of this thesis was to assess dietary intake, anthropometry and physical activity of adolescents according to sex and socioeconomic status (SES) and to investigate food perceptions of adolescents living in urban and rural areas of Cameroon. Methods: Girls and boys, 12-16 years of age, were randomly selected from schools in urban and rural areas. Food frequency questionnaire, 24-hour dietary and physical activity recalls, anthropometric measurements, qualitative interviews and a background questionnaire were used for data collection. Results: The proportion of overweight was three times higher in girls (14%) compared to boys (4%). Stunting and underweight were more common among boys (15% and 6%) than girls (5% and 1%). The prevalence of stunting was two times higher among the urban adolescents with low SES (12%) compared to those with high SES (5%). The rural adolescents had the highest proportion of stunting but more muscle that the urban adolescents. The rural adolescents ate in order to live and to maintain health. Urban adolescents with low SES ate in order to maintain health, while those with high SES ate for pleasure. More than 30% of the adolescents skipped breakfast in the urban area. Urban adolescents with high SES and girls reported a more frequent consumption of in-between meals and most food groups compared to the rural adolescents, boys and those with low SES. Over 55% of the adolescents had a protein intake below 10% of the energy (E%). Twenty-six percent of the adolescents had fat intake below 25 E%, and 25% had fat intake above 35 E%. A large proportion of the adolescents had an intake of micronutrients below the estimated average recommendation. Boys and the adolescents with low SES reported a higher energy expenditure and physical activity level than girls and the adolescents with high SES, respectively. Both under- and over-reporting of energy intake were common among the adolescents. Conclusions: The present study showed that nutrient inadequacy, stunting, underweight, as well as overweight and obesity were common among the adolescents in Cameroon. Therefore an intervention program targeting both under- and overnutrition among school adolescents is needed. Sex and socioeconomic differences also need to be considered.

No description available.

No description available.

Les taux d’insécurité alimentaire (IA) chez les Premières Nations au Canada sont plus élevés que chez les Canadiens de la population générale. L’IA est généralement associée à des apports nutritionnels moins avantageux, toutefois peu d’études se sont penchées sur cette question pour les Premières Nations vivant sur-réserve. Le but de cette recherche est de déterminer, à partir de 550 observations, s’il existe une association entre le niveau de sécurité alimentaire et les apports nutritionnels chez des adultes (> 18 ans) des Premières Nations sur-réserve du Manitoba et d’identifier les types d’aliments qui pourraient expliquer les différences statistiquement significatives. Chez les hommes, aucune des différences statistiquement significatives entre les niveaux de sécurité alimentaire pourraient avoir un effet notable sur la santé nutritionnelle puisque les nutriments en question ne sont pas « à risque » dans la population. Chez les femmes, les apports sont significativement différents entre les niveaux de sécurité alimentaire pour quelques nutriments qui sont « à risque » dans la population. Pour les femmes de 19-30 ans en IA, les apports sont supérieurs en vitamine A, en folate et en calcium. En contraste, les apports sont inférieurs en vitamines A et B6 et en potassium pour les femmes de 31-50 ans en IA, et inférieurs en vitamine B6 pour les femmes de 51-70 ans en IA. Lorsque les apports sont ajustés pour les apports énergétiques, les différences demeurent seulement statistiquement significatives pour la vitamine B6 chez les femmes de 31-50 ans et 51-70 ans. Les groupes d’aliments potentiellement responsables des différences sont identifiés. En conclusion, chez les Premières Nations du Manitoba, peu d’associations statistiquement significatives ont été identifiées entre le niveau de sécurité alimentaire et les apports en nutriments considérés « à risque » dans la population. Ceci est particulièrement le cas après ajustement pour la multiplicité des tests statistiques effectués. / Food insecurity (FI) rates in First Nations of Canada are much higher as compared to Canada’s general population. FI is generally related to lower quality diets, however, few studies have evaluated this in First Nations on-reserve. The goal of this study was to identify, using data from 550 individuals, whether nutrient intakes were related to food security status in Manitoba First Nation adults (>18 years old) on-reserve. Furthermore, the types of foods that could be responsible for the statistically significant differences were identified. In men, none of the significant differences between food security levels could have had an effect on either group’s nutritional health given that these nutrients are not considered « at risk » in the population. As for women, intakes were significantly different between food security groups for a few nutrients at risk in the population. For women 19 to 30 years of age, intakes of vitamin A, folate and calcium were significantly higher in those with FI status. On the other hand, intakes of vitamins A and B6 and potassium were significantly lower in FI 31-50 year old women, and intakes of vitamin B6 were lower in FI 51-70 year old women. Only intakes of vitamin B6 in 31-50 and 51-70 year old women remained significant in the analysis where nutrient intakes are adjusted for energy intakes. Foods that are potentially responsible for these significant differences were identified. In conclusion, few nutrients at risk were significantly associated with food security status in Manitoba First Nations. This is particularly true if statistics are adjusted for the multiple comparisons problem (Bonferroni correction).

<p>  </p> <p>Food insecurity describes the lack of access to foods and affects 10.2% of general U.S. households and 27% of low-income households in 2021. Food insecurity is a pervasive public health concern in the United States and has been linked to poor dietary intake and diet quality, overweight and obesity (especially among women), and risk of other chronic diseases, such as diabetes, hypertension and dyslipidemia. </p> <p>To better understand food security status and address its associated health and dietary outcomes among low-income populations, a conceptualized model was built and served as research framework for the dissertation, including 1) internal factors and motivations, such as traits related to self-efficacy and sufficiency that may influence diet and health; 2) external factors of temporary support, such as financial benefits from assistance programs that low-income populations are eligible for that may influence diet and health; and 3) external factors of potentially long-term support, such as nutrition education programs targeting low-income groups that may foster internalized knowledge that could sustain impact and improvement of diet and health in the long-term. Each chapter of this dissertation addresses a component of the model.</p> <p>Cross-sectional analysis of a sample of rural veterans using food pantries quantified psychological traits related to self-motivation and efficacy including grit and help seeking, at the individual and internal factors level of the conceptualized model, and their links to food security and resource use, and revealed an inverse association between grit score and risk of food insecurity. The findings provided evidence for future interventions targeting food insecurity improvement to include education and resources that address traits related to self-efficacy, such as grit, among low-income populations to improve health outcomes directly or through improving food security or use of resources. </p> <p>Using nationally representative data, the second study investigated relationships between food assistance through the Supplemental Nutrition Assistance Program (SNAP) participation, a type of societal level external support, and dietary outcomes among low-income older U.S. adults. There were no differences in dietary quality, usual nutrient intake or risk of inadequacy between SNAP participants and eligible nonparticipants. Furthermore, results revealed a high prevalence of not meeting the Estimated Average Requirement from dietary sources for several nutrients (vitamins A, C, D, E, calcium, and magnesium) but the prevalence was lower when nutrients from dietary supplements were included. The results highlight a need for continued effort to improve nutrient and dietary intake among low-income older adults.</p> <p>External factors of potentially long-term support (e.g. nutrition education and food assistance) were evaluated for relationships with body mass index. A longitudinal sample of low-income women interested in participating in nutrition education through SNAP-Education (SNAP-Ed) was examined to determine the relationship between nutrition education (SNAP-Ed) and food assistance program participation through (SNAP, WIC), separately and in combination, with long-term changes in body mass index. No differences in changes of weight status over time were observed by nutrition education, food assistance, or combination participation. The prevalence of obesity was high among this sample, calling for targeted obesity prevention interventions and further support of healthy lifestyle promotion among low-income populations. </p> <p>The findings shown in this dissertation further reveal a high health burden among low-income groups. The studies filled several research gaps described in the conceptualized model. The results may be used to inform future tailored interventions to address food insecurity, dietary and health outcomes at individual and societal levels, incorporating internal motivation and external support to mediate health and dietary risks among low-income population.</p>