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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.
51

Efeitos comportamentais e bioquímicos da farmacopuntura em ratos obesos

Pontes, Mariana Chiste January 2015 (has links)
A obesidade e todas as alterações metabólicas relativas ao excesso de peso são tratadas como o mal do século. Desta forma, justifica-se os esforços para traçar estratégias de tratamento. A acupuntura é relatada como técnica milenar de terapia chinesa e é descrita como um método de tratamento da obesidade. Esta técnica da medicina tradicional chinesa vem sendo difundida no ocidente e sendo mais estudada a partir de métodos científicos. A farmacopuntura com o uso de veneno de abelhas, um dos tipos de acupuntura, se destaca pela ação mais prolongada em relação à acupuntura tradicional. Assim, o objetivo do presente estudo foi de analisar os efeitos bioquímicos e comportamentais do uso de técnicas de farmacopuntura em ratos Wistar obesos. Para tanto, foram utilizados 160 animais: 80 foram submetidos a uma dieta hipercalórica, sendo que os animais atingiram peso superior significativo em relação ao grupo controle, e 80 animais, receberam dieta padrão. Cada grupo foi separado em subgrupos contendo 10 animais cada. Os tratamentos consistiram na estimulação de acupontos descritos na medicina tradicional chinesa para o tratamento da obesidade. Os 4 pontos avaliados foram: Fenglong (st40), Liangmen (st21), Zusanli (st36), Tianshu (st25). O grupo controle consistiu na aplicação de acupuntura em local que não corresponde a um acuponto. Os parâmetros bioquímicos analisados foram: triglicerídeos, glicose e colesterol plasmáticos. As análises comportamentais utilizadas foram o teste de labirinto em cruz elevado e teste de comportamento alimentar. A partir do presente estudo foi possível constatar que os pontos, Liangmen (st21), Zusanli (st36), Tianshu (st25) apresentaram resultados satisfatórios ao serem utilizados para a perda de peso corporal, sendo que Liangmen (st21), Zusanli (st36), Tianshu (st25) exibiram resultados promissores na redução de colesterol, glicose e triglicerídeos plasmático. O ponto Liangmen (st21) foi considerado ansiolítico e os pontos Zusanli (st36), Tianshu (st25) foram considerados como redutores do comportamento apetitivo. A partir do presente estudo foi possível depreender que através do método de farmacopuntura com veneno de abelha nos pontos st36, st25 e st21 em ratos obesos foi observada redução de peso corporal e dos parâmetros bioquímicos avaliados e indicou ação ansiolítica. / Obesity and all the metabolic changes related to excess weight are treated as the disease of the century. Thus, it is justified efforts to trace treatment strategies. Acupuncture is reported as a ancient technique of Chinese therapy and is described as an obesity treatment method. This technique of traditional Chinese medicine has been widespread in the Westand being more studied from scientific methods. The farmacopuncture using bee venom, a type of acupuncture, that stands out for longer action in relation to traditional acupuncture. The objective of this study was to analyze the biochemical and behavioral effects of using farmacupuncture techniques in obese Wistar rats. For this purpose, 160 animals were used, of which 80 were subjected to a high calorie diet, and the animals achieved significantly greater weight than the control group, and 80 animals that received standard diet. Each treatment was separated into subgroups of 10 animals each. Treatments consisted in stimulating acupoints described in Chinese traditional medicine for the treatment of obesity. For this, 4 points will be evaluated: Fenglong (st40), Liangmen (st21), Zusanli (st36), Tianshu (st25). The control group consisted of the application of acupuncture in a place that does not match an acupoint. The biochemical parameters were analyzed: triglycerides, glucose and cholesterol plasmatic. Behavioral analysis used were plus maze test and testfeeding behavior. From the present study it was found that the points, Liangmen (st21), Zusanli (st36), Tianshu (st25) showed satisfactory results when used for weight loss, and Liangmen (st21) Zusanli (st36), Tianshu (st25) showed promising results in reducing cholesterol, glucose and plasma triglycerides and the Liangmen point (st21) was considered anxiolytic and that the Zusanlipoint (st36), Tianshu (st25) were deemed to reduce the appetitive behavior. In the present study it was possible to conclude that the farmacopuncture with bee venom in points st36, st25 and st21 in obese rats reduced the body weight and the biochemical parameters and presented anxiolytic action.
52

Uso espacial do campo nativo por bovinos e a influência de fatores bióticos e abióticos no processo de pastejo / Spacial use of heterogeneous environment and the influence of biotic and abiotic factors in grazing heifers in native pasture

Santana, Marcela Moreira January 2016 (has links)
O trabalho foi conduzido na EEA-UFRGS, em Eldorado do Sul/RS no período de setembro de 2014 a maio de 2015 com o objetivo de avaliar a importância relativa da estrutura da vegetação e das variáveis abióticas (posição das cercas, da água, da porteira e do sal) sobre o pastejo de novilhas em campo nativo e avaliar se a introdução de sal em pontos estratégicos muda o uso relativo do espaço no ambiente de pastejo, por novilhas em campo nativo do bioma Pampa. Foi utilizada uma área onde é conduzido um ensaio de longa duração onde a pastagem natural é manejada sob níveis de oferta de forragem (kg de maté ria seca . kg de peso vivo-1) há 30 anos, sendo que para este experimento foram utilizadas as ofertas de 2, 3, 4 e 2-3 (2 durante a primavera e 3 no restante do ano). Novilhas de 12 meses foram monitoradas com GPS em intervalos de 2 minutos, gerando mapas de utilização da área. Foram identificadas áreas subutilizadas, onde foram inseridos blocos de sal de maneira estratégica. Foram feitas avaliações com o objetivo de caracterizar a estrutura da vegetação antes e depois da colocação do sal nos piquetes. Através de modelo linear foi analisada a influência dos fatores bióticos - altura da vegetação, biomassa do estrato inferior e entouceiramento - e abióticos - água, cercas e sal - no pastejo antes e depois da introdução do sal. Para todos os fatores (água, cerca, altura da vegetação, biomassa e entouceiramento) houve influência muito significativa (P < 0,001), em efeito simples ou quadrático, antes do uso do sal. Após a colocação do sal houve também influência muito significativa (P < 0,001) de todos fatores. O efeito da interação do tratamento (sal estratégico) com sal foi pouco significativa (P < 0,010), bem como para a interação com biomassa (P < 0,045). Os fatores bióticos não são fixos, sofrendo alteração não apenas do pastejo, mas também das condições climáticas, assim como estas interferem no comportamento animal. Nos mapas de vegetação podemos ver diminuições de entouceiramento, no entanto quando analisada a estrutura da vegetação não modificou com o uso estratégico do sal, isso pode ter ocorrido pelo curto período do experimento, que não foi suficiente para alterar a vegetação. Estudos com maior tempo de observação são necessários para avaliar o efeito da mudança de pontos atrativos na vegetação. / The study was conducted in the EEA-UFRGS, in Eldorado do Sul / RS from September 2014 to May 2015 in order to assess the relative importance of the structure of vegetation and abiotic variables (position of the fences, the water, gate and salt) on the grazing heifers in native pasture and assess whether the introduction of salt at strategic points changes the relative use of space in the grazing area for heifers in native pasture un the Pampa biome. An area where it is conducting a long-term experiment where natural pasture is managed under herbage allowance levels was used (kg dry matter. kg live weight -1) since 30 years, and for this experiment were used the treatments 2, 3, 4 and 2-3 (2 during spring and 3 the rest of the year). Heifers with 12 months were monitored with GPS using 2-minute intervals, generating maps of use of the area. Were identified underutilized areas, where salt blocks were placed strategically. Evaluations were made in order to characterize the vegetation structure before and after putting salt on the paddocks. Through linear model was analyzed the influence of biotic - vegetation height, lower stratum biomass and tussocks - and abiotic factors - water, fences and salt - in grazing before and after the introduction of salt. For all factors (water, fence, vegetation height, biomass and tussocks) was very significant influence (p <0.001), in single or quadratic effect, before use of the salt. After placing the salt was also very significant influence (p <0.001) for all factors. The effect of the interaction of treatment (strategic salt) with salt was low significant (P <0.010), as well as interaction with biomass (P <0.045). Biotic factors are not fixes, suffering not only change the grazing, but also the weather, as these interfere in animal behavior. In vegetation maps can see tussocks decreases, however when analyzing the vegetation structure did not change with the strategic use of salt, this may be due to the short period of the experiment, which was not enough to change the vegetation. Studies with more observation time is needed to evaluate the effect of changing attractive points in the vegetation.
53

Efeitos da reposição terapêutica central de melatonina em animais pinealectomizados - implicações no comportamento alimentar e peso corporal. / Effects of therapeutic central replacement of melatonin in pinealectomized animals - implications on feeding behavior and body weight.

Ferreira, Rosana Fátima Dantas 12 February 2015 (has links)
A melatonina é um hormônio que possui ritmos circulatórios robustos e previsíveis. Em animais pinealectomizados a concentração plasmática de melatonina é abolida e acompanha alterações fisiológicas como resistência à insulina e desequilíbrio entre requerimento e mobilização energética do tecido adiposo. Este estudo objetivou avaliar os efeitos da suplementação de melatonina central, através de injeção intracerebroventricular (ICV). Os resultados obtidos indicam que a pinealectomia, provoca um aumento do consumo alimentar e um considerável aumento de peso. Mostrou-se, ainda, que a reposição ICV de melatonina é capaz de provocar a diminuição do consumo alimentar, assim como uma diminuição expressiva do peso corporal. Observou-se, também, que a administração de melatonina nos animais controles regularizam o peso corpóreo, impedindo o aumento de peso próprio do avançar da idade e que a melatonina foi um agente importante na redução de gordura corporal. / Melatonin is a hormone with robust and predictable rhythms being a strong synchronizer for the expression of several physiological processes. But in pinealectomized rats plasma concentration of melatonin is abolished, leading to physiological changes such as insulin resistance and imbalance between energy requirement and mobilization from adipose tissue. The aim of the study was to evaluate the effects of intracerebroventricular supplementation of melatonin. We studied food intake, weight gain and peripheral insulin sensitivity. The results obtained indicate that the pinealectomy caused an increase in food consumption and a considerable weight gain. Furthermore, icv melatonin replacement in these animals counteracted both effects. It was observed also that melatonin in control animals regulates body weight, preventing weight gain characteristic of aging. Finally, it was also observed that melatonin-induced decrease in body weight is due to a reduction of fat adipose tissues.
54

Distúrbios alimentares e sua associação com erosão e cárie dentária em adolescentes

Brandt, Lorenna Mendes Temóteo 29 July 2015 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-03-01T18:01:20Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) PDF - Lorenna Mendes Temóteo Brandt.pdf: 2197643 bytes, checksum: e9be9f110b92c39a5a03930b51b276eb (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-06-13T20:28:07Z (GMT) No. of bitstreams: 2 PDF - Lorenna Mendes Temóteo Brandt.pdf: 2197643 bytes, checksum: e9be9f110b92c39a5a03930b51b276eb (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-06-13T20:29:26Z (GMT). No. of bitstreams: 2 PDF - Lorenna Mendes Temóteo Brandt.pdf: 2197643 bytes, checksum: e9be9f110b92c39a5a03930b51b276eb (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-07-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The damages in the oral health of individuals with eating disorders have been investigated, bringing conflicting questions about the involvement of the teeth. Therefore, a controlled cross-sectional study was carried out in order to evaluate the occurrence of erosion and dental caries in 15-18-year-old adolescent women who are at risk of suffering from eating disorders and compare them to healthy adolescents. The probabilistic sample consisted of 850 adolescents from public and private schools in Campina Grande - PB. The presence of behavioral risk for developing eating disorders was assessed using the Bulimic Investigatory Test of Edinburgh (BITE). Eating and oral hygiene habits were also investigated through a questionnaire. Anthropometric measurements (weight and height) to calculate the body mass index were measured. For evaluation of dental caries and dental erosion dental examinations were performed through the CPO-D index and the O'Sullivan index, respectively. The examiners for the diagnosis of dental caries and dental erosion remained blind to the condition of each adolescent regarding to the presence of risk behavior for disorders. The data were analyzed descriptively and inferentially using the SPSS 18.0 software. The association between the incidence of dental erosion and dental caries, and eating and oral hygiene habits was detected through a process of bivariate analysis using the Pearson's chisquared and Fisher's exact tests. A conditional logistic regression model (backward) was used to determine the association of the independent variables with risk behavior for bulimia nervosa. The prevalence of risk behaviors for eating disorders was 4.8%, with 1.5% (n = 13) of adolescents with severe risk behavior for eating disorders. Every teenager with risk was matched by school and age with four other without risk (controls). No association was found between high behavioral risk for eating disorders and dental caries (p = 0.329; OR = 2.2, 95% CI: 0.35 to 13.72) or with dental erosion (p = 0.590; OR = 2, 33, 95% CI: 0.56 to 9.70). No association was observed between eating habits and dental caries and dental erosion (p> 0.05). Logistic regression revealed that the case group was identified with significantly higher chances of having high BMI when compared to the control group (p = 0.031; OR = 5.1; 95% CI: 1.61 to 23.07). It was concluded that there was no association between risk behaviors for eating disorders and dental caries and dental erosion, but high BMI was a risk factor for developing eating disorders. / Os prejuízos na saúde bucal de indivíduos portadores de distúrbios alimentares vêm sendo investigados, trazendo consigo questões discordantes quanto ao comprometimento dos dentes. Diante disso, realizou-se um estudo transversal controlado, com o objetivo de avaliar a ocorrência de erosão e cárie dentária em adolescentes mulheres, de 15 a 18 anos, em risco de estarem sofrendo de distúrbios alimentares e compará-las a adolescentes saudáveis. A amostra probabilística foi composta por 850 adolescentes de escolas da rede pública e privada de Campina Grande - PB. A presença de risco comportamental para desenvolvimento de distúrbios alimentares foi avaliada através do Bulimic Investigatory Test of Edinburgh (BITE). Hábitos alimentares e de higiene bucal também foram investigados por meio de um questionário. Foram aferidas medidas antropométricas (peso e altura) para o cálculo do índice de massa corporal. Para avaliação de cárie e erosão dentária foram realizados exames odontológicos, através dos índices CPO-D e O’Sullivan, respectivamente. Os examinadores para o diagnóstico de cárie e erosão dentária se mantiveram cegos quanto à condição de cada adolescente no que se refere à presença de comportamento de risco para os distúrbios. Os dados foram analisados de forma descritiva e inferencial através do software SPSS 18.0. A associação entre a ocorrência de erosão dentária e cárie dentária, e hábitos alimentares e de higiene bucal, foi verificada através de um processo de análise bivariada, utilizando os testes do Qui–quadrado de Pearson e Exato de Fisher. Um modelo de regressão logística condicional (backward) foi usado para determinar a associação das variáveis independentes com comportamento de risco para bulimia nervosa. A prevalência de comportamento de risco para distúrbios alimentares foi de 4,8%, com 1,5% (n=13) das adolescentes apresentando grave comportamento de risco para distúrbios alimentares. Cada adolescente com risco (caso) foi pareada por escola e idade com outras quatro sem risco (controles). Não foi observada associação entre alto risco comportamental para distúrbios alimentares e cárie dentária (p=0,329; OR= 2,2, 95% IC: 0,35-13,72) nem com erosão dentária (p = 0,590; OR = 2,33; 95% IC: 0,569,70). Não foi observada associação entre hábitos alimentares e cárie e erosão dentária (p> 0,05). A regressão logística revelou que o grupo caso foi identificado com chances significativamente maiores de possuir IMC elevado quando comparado ao grupo controle (p=0,031; OR = 5,1; IC 95%: 1,61-23,07). Concluiu-se que não houve associação entre comportamento de risco para distúrbios alimentares e cárie e erosão dentária, porém o IMC elevado foi uma condição de risco para o desenvolvimento de distúrbios alimentares.
55

Res?duo ?mido de Cervejaria na Alimenta??o de Cabras. / Use of Wet Brewery Residue for Lactating Goats.

Silva, Viridiana Basoni 14 February 2007 (has links)
Made available in DSpace on 2016-04-28T14:59:46Z (GMT). No. of bitstreams: 1 2007 - Viridiana Basoni Silva.pdf: 2120660 bytes, checksum: 288bfedc4575c16c602010bb3ef36609 (MD5) Previous issue date: 2007-02-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work was accomplished with aim of evaluate intake and apparent digestibility of nutrients, nitrogen balance, feeding behavior and water balance in lactating goats, fed with diets contend different levels of substitution of the concentrate by wet brewery grains (WBG): 0, 25, 50, 75 and 100%. Five goats Boer x Saanen and five Saanen goats were randomly assigned in two 5x5 Latin squares. The five experimental periods had duration length of 15 days, 10 for adaptation and five days for data and sample collections. The roughage used was tifton hay, in roughage:concentrated rate of 60:40. The animals were allocated in metabolic cages, fed twice a day. For the feeding behavior the feeding times (FT), idle time (IT) and rumination time (RT) were evaluated for each animals every 20 minutes during 24 hours. The dry matter intake (DMI), organic matter (OMI), crude protein (CPI), ether extract (EEI) neutral detergent fiber (NDFI) and total digestible nutrients (TDNI) in g/d and dry matter intake body weight (DMI BW) and neutral detergent fiber intake body weight (NDFI BW) had quadratic effect, diets more consumed were the with levels of substitution of 0 and 25%. The apparent digestibility of the dry matter (DM), organic matter (OM) and total carbohydrate (CT) decreased with linear effect with the increase of the levels of WBG in the diet and the digestibility of CP it had quadratic effect, increasing digestibility to the level of substitution of 25% of WBG of concentrate. The nitrogen balance had decreased linear effect lesser with increasing WBG. The feeding times (FT) and idles times (IT), weren t affected by increasing of levels of WBG in the diet, however, the rumination times and total chewing time had growing linear effect with increase of levels of WBG in the diet. The alimentary efficiency (ALE) and rumination efficiency (RUE) in DM/h had decreasing linear effect with increase of WBG in the diet, but when ALE NDF/h obtained a quadratic effect where larger efficiency were observed in the diets with 50% of WBG, RUENDF had decreased linear effect with increase of levels of WBG. The water balance was also influenced by the increase of the levels of WBG in diet, where larger intakes and excretions were obtained by animals that intake diet without WBG in its composition. Increases of levels of WBG decreased intake and excretions of water. It can be concluded the at diet can be used up to 50% of replacing of concentrate in the diets of lactating goats. / Este trabalho foi realizado com o objetivo de avaliar o consumo, a digestibilidade aparente dos nutrientes, o balan?o de nitrog?nio, comportamento alimentar e balan?o h?drico em cabras lactantes, alimentadas com dietas contendo diferentes n?veis de substitui??o do concentrado por res?duo ?mido de cervejaria (RUC): 0, 25, 50, 75 e 100%. Foram utilizadas cinco cabras mesti?as Boer x Saanen e cinco cabras Saanen distribu?das em dois quadrados latinos 5x5. Os cinco per?odos experimentais tiveram dura??o de 15 dias, sendo 10 de adapta??o e cinco dias de coleta de dados e de amostras. O volumoso utilizado foi o feno de tifton, na rela??o volumoso: concentrado de 40:60. Os animais foram alojados em gaiolas metab?licas, alimentados duas vezes ao dia. Na avalia??o do comportamento alimentar foram medidos os tempos dispendidos com alimenta??o, tempo de rumina??o e tempo de ociosidade que foram avaliados por observa??es dos animais a cada 20 minutos at? completarem 24 horas. O consumo de mat?ria seca em kg e em porcentagem do peso vivo (% PV), mat?ria org?nica, prote?na bruta, extrato et?reo, carboidratos totais e nutrientes digest?veis totais em g/d e fibra em detergente neutro em gramas e %PV, apresentaram resposta quadr?tica, onde as dietas mais consumidas foram a sem inclus?o de RUC e com n?vel de substitui??o de 25%. Observou-se resposta linear decrescente para a digestibilidade aparente da MS, MO e CT de acordo com o aumento dos n?veis de RUC na dieta e resposta quadr?tica para digestibilidade da PB , onde maior digestibilidade ocorreu na dieta com n?vel de substitui??o de 25% de RUC. O balan?o de nitrog?nio obteve resposta linear decrescente com o aumento de RUC na dieta. O tempo gasto com alimenta??o (TA) e com ociosidade (TO), n?o diferiram (P>0,05) quanto aos n?veis de RUC na dieta, no entanto, resposta linear crescente foi observada para os tempos dispendidos com rumina??o e com a mastiga??o total, com o aumento dos n?veis de RUC na dieta. A efici?ncia alimentar (EAL) e a efici?ncia de rumina??o (ERU) expressas em MS/h obtiveram resposta linear decrescente com o aumento de RUC na dieta, mas quando expressas em FDN/h a EAL obteve resposta quadr?tica onde maiores efici?ncias foram observadas nas dietas com 50% de RUC, a efici?ncia de rumina??o expressa em FDN/h apresentou resposta linear, diminuindo ? medida que aumentavam os n?veis de RUC. O balan?o h?drico tamb?m foi influenciado pelo aumento dos n?veis de RUC na dieta, onde animais que consumiram as dietas com 0% de RUC apresentaram maiores consumos e excre??es. ? medida que aumentaram os n?veis de RUC, menor foi o consumo e excre??o de ?gua. Concluiu-se que o RUC pode ser utilizado em at? 50% de substitui??o do concentrado na dieta de cabras lactantes.
56

Efeito de diferentes dietas sobre a modulação do comportamento alimentar em vias homeostáticas e hedônicas em ratas fêmeas

Laureano, Daniela Pereira January 2013 (has links)
Introdução: A exposição crônica a diferentes tipos de dieta altera o metabolismo hipotalâmico e mesolímbico, podendo causar alterações no comportamento alimentar do indivíduo. O BDNF, fator de crescimento neuronal, pode atuar na modulação do comportamento alimentar tanto em vias hedônicas quanto homeostáticas. O objetivo do estudo foi investigar como o BDNF atua na modulação do comportamento alimentar em vias homeostáticas e hedônicas em ratas fêmeas com diferentes perfis metabólicos. Materiais e métodos: Ratas Wistar fêmeas adultas randomizadas por peso foram divididas em: dieta controle (C) contendo 22% de proteína e 4% de lipídios; dieta hipoproteica (LP) 8% de proteína ou dieta hiperlipídica (HF) 45% de lipídios, ad libitum, por 5 semanas, sendo o consumo medido a cada 72 horas e o peso semanalmente. O trabalho foi dividido em duas partes. Na primeira parte, após as 5 semanas de dieta os animais ficaram em jejum por 4 horas e foram expostos ao alimento doce (Froot Loops®), previamente pesado, por 1 hora, a fim de verificar o consumo de alimento palatável em ratas com diferentes perfis metabólicos. Imediatamente após coletou-se sangue e cérebro, assim como, o peso da gordura abdominal foi mensurado. Na segunda parte do estudo, após as 5 semanas de dieta, os animais ficaram durante 7 dias no BioDAQ®, um sistema computadorizado de análise do comportamento alimentar, para avaliar o consumo da dieta habitual em ratas com diferentes perfis metabólicos. O consumo foi mensurado através de mordidas (diferença de 0,1 g na balança) e refeições (conjunto de porções por um tempo igual ou menor a 15 min, porções são mordidas ininterruptas). No dia 10 foi realizado o teste de preferência alimentar no qual o animal poderia escolher entre a dieta habitual (dieta que eles receberam por 5 semanas) ou a dieta hipersacarídica (HP) (contendo 34% lipídios, 30,2% carboidratos, 14% proteínas, 20% sacarose), com duração de 20 horas. Após 1 semana, foi coletado sangue, cérebro e mensurada a gordura abdominal. Foi realizado western blotting para tirosina hidroxilase (TH) e fosfo- tirosina hidroxilase (pTH) no núcleo accumbens, STAT3 e fosfo-STAT3 (pSTAT3) no hipotálamo. Adicionalmente, foi mensurado BDNF no soro, no núcleo do trato solitário (NTS), área tegmentar ventral (VTA) e glicemia no soro. Resultados: Nas 5 semanas de tratamento, em relação ao ganho de peso dos animais não houve diferenças significativas entre os grupos, não houve interação, apenas apresentaram efeito do tempo (p< 0,001). A gordura abdominal foi maior nas ratas HF (p= 0,002) e LP (p= 0,023) em relação aos controles. Os animais que receberam dieta HF comeram menos gramas de Froot Loops® do que os animais controle (p= 0,003). Durante a habituação ao BioDAQ® não houve diferença significativa no consumo de dieta entre os grupos. Na análise do comportamento alimentar no BioDAQ®, comparando os grupos controle versus hiperlídica (C x HF), animais HF tiveram o tamanho da refeição (g) (p=0,049), número de porções (p= p< 0,001), tamanho da refeição ciclo escuro (p= 0,002), número de porções ciclo escuro (p < 0,001) menor do que os controles e tamanho da porção ciclo escuro (p=0,006) maior do que os controles. Na análise do comportamento alimentar, comparando os grupos controle versus hipoproteica (C x LP) foram encontradas diferenças significativas nos seguintes parâmetros: média do tamanho da porção (g) (p= 0,004), média do tamanho da porção no ciclo claro (g) (p= 0,042), média do tamanho da refeição no ciclo escuro (g) (p= 0,035), média do tamanho da porção no ciclo escuro (g) (p= 0,006). Em todos os parâmetros os animais LP tiveram uma média maior do que os animais controle. No teste de preferência alimentar, os animais HF apresentaram uma média inferior aos animais controle nos seguintes parâmetros: consumo de dieta hipersacarídica (Kcal) (p= 0,034), número de refeições de dieta hipersacarídica (p= 0,016), número de porções de dieta hipersacarídica (p= 0,001). Os animais HF apresentaram médias superiores aos animais C em relação ao tamanho da porção de dieta hipersacarídica (g) (p= 0,023), PMI (intervalo entre refeições) total de dieta hipersacarídica (p= 0,022), saciedade total de dieta hipersacarídica (p= 0,008). Durante o teste de preferência alimentar comparando-se controle versus hipoproteica (C x LP), os animais (LP) apresentaram o consumo de dieta hipersacarídica (kcal) (p= 0,030) e o número de porções de dieta hipersacarídica (p= 0,003) menor que os animais controles. Os animais LP apresentaram saciedade total de dieta hipersacarídica (p= 0,046) maior do que os controles. Não houve diferenças significativas nos níveis de glicemia no soro entre os grupos. Os animais HF apresentaram as médias de pSTAT3 maior do que os controles (p= 0,013) e fosfo-tirosina hidroxilase menor do que os controles (p= 0,05). Os animais LP apresentaram STAT3 menor do que os animais controle (p= 0,035) e tiveram resultados de BDNF próximos da significância (p=0,053), tendo apresentado uma média inferior aos animais controle. Conclusões: A exposição aos diferentes tipos de dieta muda os padrões de alimentação bem como a estrutura corpórea. Tanto animais expostos a dieta HF quanto a LP apresentam alterações compatíveis com um estado de pré-resistência à leptina. O BDNF parece modular as vias homeostáticas e hedônicas do comportamento alimentar, no entanto mais estudos são necessários para entendermos melhor esses mecanismos. / Introduction: The chronic exposure to different types of diet modifies the hypothalamic and mesolimbic metabolism, what can lead to changes in the individual feeding behavior. BDNF, a neuronal growing factor, can act modulating feeding behavior in hedonic as well as in homeostatic pathways. The aim of this study was to investigate how BDNF acts modulating feeding behavior regarding hedonic and homeostatic pathways in female rats with different metabolic profiles. Materials and methods: Female adult Wistar rats randomized by weight were divided in: control diet (C) with 22% of protein and 4% of lipids; low-protein diet (LP) with 8% of protein or high fat diet (HF) with 45% of lipids, ad libitum, for 5 weeks, with the diet consumption verified every 72 hours and the weight verified weekly. The study was divided in two parts. In the first part, after 5 weeks receiving diet, animals were submitted to 4 hours of fasting and then were exposed to sweet food (Froot Loops®), previously weighted, for 1 hour to verify the palatable food consumption in rats with different metabolic profiles. Immediately after, blood and brain were collected and the abdominal fat weight was verified. In the second part of the study, after 5 weeks receiving diet, the animals were submitted to the BioDAQÒ, a computer system of feeding behavior analyses, to evaluate the habitual diet consumption in rats with different metabolic profiles for 7 days. The consumption was measured through bites (0.1g of difference in the scale) and meals (a group of portions for a period of time less or equal than 15min, portions are uninterrupted bites). On day 10 the food preference test was done and the animals could choose between the habitual diet (the one they have received for 5 weeks) and the high sucrose palatable diet (HP) (with 34% of lipids, 30.2% of carbohydrates, 14% of protein, 20% of sucrose) for a period of 20 hours. After one week, blood and brain were collected and abdominal fat was measured. Western blotting was used to verify the content of tyrosine hydroxylase (TH) and phospho-tyrosine hydroxylase (pTH) in the nucleus accumbens, STAT3 and phospho-STAT3 (pSTAT3) in the hypothalamus. Additionally, BDNF was measured in the serum, in the solitary tract nucleus (NTS) and in the ventral tegmental area (VTA) and glycemia was also verified. Results: Considering the 5 weeks of treatment regarding animals weight gain there was no significant difference between groups and no interaction, only an effect of time (p<0.001). Abdominal fat was higher in HF (p=0.002) and LP (p=0.023) rats comparing to controls. Animals that received HF diet ate less grams of Froot Loopsâ than controls (p=0.003). During the habituation to the BioDAQÒ no significant difference was seen in the consumption of the diet between the groups. When analyzing feeding behavior in the BioDAQÒ, comparing control against high fat groups (C x HF), HF animals had a decrease in the size of the meal (g) (p=0.049), number of portion (p<0.001), meal size in the dark phase (p=0.002), number of portions in the dark phase (p<0.001) compared to controls while the size of the portion in the dark phase (p=0.006) was bigger than controls. Analyzing feeding behavior comparing control against low-protein groups (C x LP) a significant difference was observed in the following parameters: average of the size of the portion (g) (p=0.004), average of the size of the portion in the light phase (g) (p=0.042), average of the size of the meal in the dark phase (g) (p=0.035), average of the size of the portion in the dark phase (g) (p=0.006). LP animals showed a higher average than controls in all parameters. In the food preference test, HF animals showed a lower average than controls in the following parameters: consumption of high sucrose palatable diet (Kcal) (p=0.034), number of meals of high sucrose palatable diet (p=0.016), number of portions of high sucrose palatable diet (p=0.001). HF animals showed higher averages than controls regarding the size of the portion of the high sucrose palatable diet (g) (p=0.023), total PMI (post interval meal) of high sucrose palatable diet (p=0.022) and total satiety of high sucrose palatable diet (p=0.008). In the food preference test comparing controls against low-protein groups (C x LP), LP animals showed a lower consumption of high sucrose palatable diet (Kcal) (p=0.030) and a lower number of portions of high sucrose palatable diet (p=0.003) than control animals. LP animals showed total satiety of high sucrose palatable diet (p=0.046) bigger than controls. There was no significant difference in the glycemia levels between groups. HF animals had pSTAT3 averages higher than controls (p=0.013) and phospho-tyrosine hydroxylase lower than controls (p=0.05). LP animals showed STAT3 lower than control animals (p=0.035) and had BDNF results close to the significance (p=0.053), showing a lower average than control animals. Conclusion: The exposure to different types of diets changes the feeding patterns as well as the body structure. Animals exposed to HF diet as well as those exposed to LP diet showed changes related to a leptin pre-resistant state. BDNF seems to modulate homeostatic and hedonic feeding behavior pathways, however more studies are necessary to a better understanding of the mechanisms.
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BEHAVIORAL AND PHYSIOLOGICAL ADAPTATIONS ASSOCIATED WITH FEED INTAKE DURING TRANSITIONING CATTLE TO HIGH-GRAIN DIETS

McLean, Amanda M. 01 January 2019 (has links)
Transitioning cattle from a high-forage to a high-concentrate diet increases the risk for ruminal acidosis and is often related to decreased feed intake, which compromises animal health and performance. Since control of feed intake and rumen motility are closely related, we hypothesized that a reduction in rumen motility may be associated with a reduction in feed intake during this transition. Computer programs were created to analyze feed disappearance and rumen pressure data for feeding behavior as well as identification and characterization of rumen contractions, respectively. This method enabled timely analysis of large datasets and removed subjectivity associated with manual analysis. In the second part of this series, cattle were moderately transitioned from a 70% to a 90% concentrate diet, and SARA was induced. Although, reductions in feed intake were modest, on day 2 of high-grain feeding, animals slowed feed consumption rate and displayed a reduction in rumen contraction frequency, amplitude, and duration. Next, an abrupt transition from 50% to 90% concentrate was used to induce ruminal acidosis and cause some animals to stop eating. The abrupt increase in dietary concentrate was also associated with reductions in rumen motility. Patterns of ruminal pH, viscosity, and motility changes were related to when cattle reduced feed intake. Endotoxin quantification in blood samples from the ruminal vein, portal vein, and mesenteric artery suggested the point of endotoxin translocation into blood was across the ruminal epithelium. Additionally, the greater the concentration of endotoxin in the plasma, the more likely animals were to go “off-feed.” By understanding the physiological and behavioral mechanisms by which cattle adapt to high-grain diets, we can improve animal health and performance through these diet transitions.
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An Examination of Modulation of Feeding Behavior in the Nurse Shark Ginglymostoma cirratum (Bonaterre 1788)

Matott, Michael 01 April 2003 (has links)
The ability of an organism to modulate its feeding behavior is an important focus of feeding ecology studies. Modulation is the ability to distinctly and consistently alter a behavior to accommodate different stimuli. The goal of this study was to examine the ability of the nurse shark Ginglymostoma cirratum to modulate its food capture behavior with different sizes and types of food items. This was carried out through kinematic and electromyographic analysis. Eight sub-adult specimens of G. cirratum were filmed feeding on two different food types (squid and fish) and sizes (gape size and larger than gape size). Filming consisted of high-speed videography utilizing a low-light digital video system. Kinematic variables related to lower jaw movement, mouth width, and head angle were measured from video footage. Up to twelve muscles in each of six specimens were implanted with bipolar electrodes to measure the onset and duration of motor activity. There were no significant differences between food sizes and any of the kinematic variables. Only two muscles showed significant differences in onset time based on food size. In regards to food types, squid bites were significantly faster than fish bites, but when examined proportionately to bite duration only the time to jaw closure remained significantly different. The motor pattern of G. cirratum demonstrates an anterior to posterior sequence, which corresponds to the anterior to posterior kinematic sequence. Little cranial elevation is present during feeding sequences and is not thought to contribute significantly to feeding. Ginglymostoma cirratum is a stereotyped, inertial suction feeder. There is little evidence that there is modulation in feeding behavior based on food size or food type. If modulation does exist in the feeding behavior, it is more likely to occur after prey capture while the prey is being processed and manipulated prior to transport. Initial observations suggested that a novel behavior termed 'spit-suck manipulation' is utilized for larger prey items.
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Neural substrates of feeding behavior : insights from fMRI studies in humans

Malik, Saima. January 2008 (has links)
Feeding behavior is a complex phenomenon involving homeostatic signals, and non-homeostatic inputs such as visual cues. In primates, exposure to food-related sensory cues has been shown to elicit cephalic phase responses as well as trigger central appetitive processing, in a motivationally-dependent manner. Neural structures consistently implicated in such responses and/or in the regulation of ingestive behavior in general, in both monkeys and in humans, include the amygdala, insula, striatum, hypothalamus, and frontal and occipital cortices. In humans however, the cerebral response to visual food stimulation remains minimally explored. / Functional Magnetic Resonance Imaging (fMRI) provides information about state-dependent changes in local neuronal activity in vivo. Using fMRI, the present dissertation examined changes in human brain activity to food and nonfood pictures following the pharmacological induction of hunger with the orexigenic hormone ghrelin (Study 1), and following manipulation of the cognitive state of food expectation (Study 2). / Our data reinforce the involvement of a distributed frontal-limbic-paralimbic circuit in the central processing of food imagery, under both experimental conditions. The first study revealed that intravenous ghrelin administration potently modulated food-associated neural responses III areas involved in reward, motivation, memory, and attention (amygdala, insula, orbitofrontal cortex, striatum, hippocampus, midbrain, visual areas). This suggests that metabolic signals such as ghrelin may promote food consumption by enhancing the appetitive response to food cues via engagement of the hedonic network. / The second study revealed that brain regions activated in the 'expectant' state (i.e. when subjects were anticipating food reward) were at least partially dissociable from those in the 'not expectant' state. In particular, recruitment of the dorsolateral prefrontal cortex, a principal component in the cognitive control network, exclusively in the 'not expectant' condition, may signal an attempt to suppress appetite in the absence of food expectation. Areas of convergence were observed in the amygdala and insula. / Obesity is rapidly becoming the major cause of excess mortality worldwide; therefore, understanding how the central nervous system controls appetite and nutrient consumption is of considerable interest. The projects in this thesis offer significant insights regarding the effects two select factors (one intrinsic and the other extrinsic) on the neural reaction to visual food stimuli, in healthy male participants.
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PARENTAL PERCEPTIONS OF NUTRITIONAL STATUS OF CHILDREN WITH AUTISM

Holt, Rachel Corliss 01 January 2008 (has links)
Literature shows that nutritional deficiency and feeding behaviors in neurodevelopmentally disabled children is secondary to an underdeveloped gastrointestinal tract. Fifty (50) parents with children with autism responded to a Nutritional Perception Assessment that they believe their children are at adequate nutritional status. They reported confidence in their nutritional knowledge, yet admitted to concern about the nutritional status of their children. The survey revealed that parents are not seeing a registered dietitian for their nutritional advice, leading to the question of soundness in nutritional information received. A marginal correlation was found between belief in adequate nutritional status of children and the use of credible sources for nutritional information, p=0.0429. Data from twenty-five 24-hour recalls was entered into the MyPyramid Food Tracker to determine nutritional status, which was compared to Daily Recommended Intakes (DRIs), showing adequate nutrient consumption.

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