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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.
391

Risk factors for malnutrition in children aged 0 to 5 Years in Lilongwe district, Malawi

Muwalo, Blessings Gandalale Chale January 2013 (has links)
>Magister Scientiae - MSc / The Malawi Multiple Indicator Cluster Survey (MICS) in 2007 indicated that the prevalence of underweight in Lilongwe District was 29%, stunting was 49% and Global Acute Malnutrition was 11%. The aim of the study therefore was to determine the risk factors for malnutrition amongst children aged 0 to 5 years in Lilongwe district in Malawi. Study design It was a case-control study, conducted in randomly selected Community Therapeutic Care (CTC) Sites (Nutrition Rehabilitation Units (NRUs)) and Under-five Clinics at health facilities of the district. The study sample was comprised of 50 underweightfor- age children (25 girls and 25 boys) aged 0 to 5 years from NRUs of the district selected randomly. The controls were comprised of 44 normal weight-for-age children (22 girls and 22 boys) randomly selected within the same age group, routinely attending under-five growth monitoring and immunization sessions during the same period as the cases. The cases and controls were identified using the NRU and under-five clinic registers respectively. Data Collection There was a face to face interview with the mother/guardians of the children, conducted by trained NRU nurse specialists, the researcher and a research assistant, using a structured questionnaire. Questions about socio-economic status of the mother/caregiver, child feeding practices, nutritional status and diseases of the child were asked. Analysis of results Data was analyzed using EpiInfo 2002 software. Ethical approval for the study was requested from the Ethical committee of the University of the Western Cape. Informed written consent was obtained from all the participants.
392

A feedlot replacement model

Freding, William Karl January 1972 (has links)
The purpose of the study was to develop a realistic method of determining the optimum replacement time of steers in a feedlot in which there are sequential feeding cycles. There are two models for steers developed and discussed in this paper. The first model optimizes the length of stay in the feedlot assuming that feedlot capacity is the limiting constraint. The second model optimizes the length of stay in the feedlot when working capital is the limiting constraint. A third model is developed to determine the optimum length of feeding time for market hogs in a feeding barn. An evaluation of each model is made. It is concluded that the cattle models have a limited use because of the high variability in performance. The hog replacement model is quite valid and can be used in a modern hog feeding enterprise. / Land and Food Systems, Faculty of / Graduate
393

Vitamin A deficiency and Eimeria acervulina infection in the chick

Coles, Barbara Margaret January 1969 (has links)
The present investigation was conducted to determine the effect of an infection with Eimeria acervulina on vitamin A deficient birds. One hundred day-old chicks were divided into 2 equal groups, and one group was raised on 440 I.U. vitamin A per kilogram of feed, while the second group received the normally recommended 4400 I.U. per kilogram. At 5 weeks of age, half the birds from each group were given an immunizing infection with 3 million oocysts of E. acervulina. The clinical symptoms were more acute, and the oocyst production, mortality, and weight losses significantly higher, in the birds on the low vitamin A diet. When the birds were 9 weeks old, half were subjected to a second infection and the other half held until they were 19 weeks old. The 9-week-old birds were given an oral inoculation of 10 million oocysts to evaluate the effect of a low vitamin A diet on: the strength of the immune response; a primary infection with E. acervulina in 9-week-old birds; and the early tissue stages of the parasite in immune and non-immune birds. The results from this experiment showed that the degree of immunity is not affected by a low vitamin A ration, but primarily determined by the severity of the initial infection; and that the primary infection in 9-week-old chicks is clinically very similar to that in younger birds. The histological examinations demonstrated that the low vitamin A level used in this study did not affect the integrity of the intestinal epithelium, nor the development of the endogenous forms of the parasite. It was also shown that the sporozoite invasion was the same in immune and non-immune birds, but the schizont development was severely inhibited in the immune birds regardless of the vitamin A level. The non-immune birds on the low vitamin A ration did not show as distinct a heterophil response to infection as did the other groups. The remaining birds, half which were immunized, were maintained on their respective diets until 19 weeks of age, and during this period there was no clinical evidence of a vitamin A deficiency, and the growth rate was not significantly affected by the level of vitamin A in the diet. When 19 weeks old, the birds were inoculated with 25 million oocysts of E. acervulina to assess the effect of an extremely heavy primary infection in older birds, and to evaluate the degree of immunity still retained 14 weeks after an initial infection. The mortality was very high, and the weight losses significantly greater, in birds on the low vitamin A dietary level. Immunity, although decreased from the earlier experiment, was still present in birds on both levels of vitamin A. / Land and Food Systems, Faculty of / Graduate
394

Evaluation of techniques employed in the study of alanine metabolism in sheep

Cooper, Donald Arthur January 1974 (has links)
In view of the importance of alanine as a gluconeogenic precursor in ruminants, the objective of the present study was to assess the effectiveness of three techniques in estimating the metabolic parameters surrounding alanine in wethers fed a maintenance diet of alfalfa hay. A preliminary experiment utilized a blood flow technique to study the net production and/or utilization of both alanine and glucose by the portal drained viscera. Such a method involved evaluating the arterio-venous concentration differences of alanine and glucose, in conjunction with determining the rate of portal vein blood flow. Radioactively labelled ¹⁴C - alanine was administered as a single injection in the second series of experiments to estimate the metabolic parameters of alanine as well as its contribution to glucose synthesis. The L-U-¹⁴C-alanine was given intravenously through previously implanted jugular catheters and the fall in the specific activity of plasma alanine with time was determined. The line of best fit for the decay curve of the specific activity of plasma alanine was constructed by means of a computer using a multi-term exponential function which enables the estimation of such parameters as the pool size, space, total entry rate, irreversible loss and recycling of alanine. The per cent conversion of alanine to glucose was determined by the corresponding peak of glucose specific activity following the single injection of ¹⁴C - alanine. The turnover of alanine was also studied using a continuous infusion of L-U-¹⁴C-alanine without a priming injection. The specific activity of plasma alanine reached a plateau five hours after the beginning of the infusion. It was from these plateau levels that the rate of irreversible loss of alanine as well as its percent conversion to glucose was estimated. The results indicated that the single injection technique was able to partition the total entry rate of alanine into irreversible loss and recycling and thus prove more informative than a continuous infusion method. The present study also suggested that under certain physiological stress conditions in ruminants, where recycling becomes prominent, a continuous infusion approach may overestimate the actual rate of irreversible loss of alanine. / Land and Food Systems, Faculty of / Graduate
395

Effects of feeding tallow protected with soybean meal or canola meal to dairy cows during the first 15 weeks of lactation

Vincente, Gail Richmond January 1981 (has links)
Soybean meal-protected tallow has been commercially available in Canada for use in dairy rations, since 1975. The reported effects of feeding protected tallow to dairy cows have been variable and the prices of protected tallow supplements have been high. In view of the lower cost of canola meal relative to soybean meal in Canada, a study was undertaken to investigate the efficacy of feeding protected tallow made either from soybean meal or canola meal, to dairy cows in early lactation. Secondly, a comparison was made between the soybean meal-protected tallow and the canola meal-protected tallow. Twenty-seven cows from the University herd, comprised of 12 first-calf Holstein heifers, 3 Holsteins in their >2nd lactation, 4 Ayrshire heifers and 8 ≥2nd lactation Ayrshires, were used in a continuous feeding trial which was conducted from day of calving until the end of week 20 of lactation. Cows were randomly assigned within breed and lactation category (9 cows per treatment) to one of 3 isonitrogenous (16 % crude protein) concentrates: a) no protected tallow (control); b) 8 % soybean meal-protected tallow; or c) 8 % canola meal-protected tallow, which they received during weeks 1-15 (inclusive). From the beginning of week 16 until the end of week 20 all cows were fed a 16 % crude protein, post-treatment concentrate (no protected tallow). Throughout the 20-week trial the ratio of concentrates to cubes offered was maintained at 70:30 with feed intakes being ad libitum. Between weeks 13 and 16, 4 cows per treatment were assigned to a digestibility trial involving a 7-day total Collection of faeces and urine. Protected tallow rations produced significant increases over the control ration (P<.05) in the yields of milk, 4 % fat-corrected milk and milk fat, and protected tallow rations increased the efficiencies of conversion of gross energy, digestible energy, crude protein and digestible protein to milk, 4 % fat-corrected milk, solids-corrected milk and milk energy (P<.05). The apparent digestibility of ether extract and the concentration of plasma non-esterified fatty acids were significantly higher on rations with protected tallow (P<.05). Milk protein % was significantly reduced below the control level with rations containing protected tallow and rumen acetate and the acetate:propionate levels were also decreased. Protected tallow rations had no significant effect on the intakes of dry matter, gross energy, digestible energy, crude protein or digestible protein or on the apparent digestibilities of dry matter, organic matter, gross energy, nitrogen, acid-detergent fibre, ash, calcium, phosphorus or magnesium (P>.05). Also the yields of solids-corrected milk, milk gross energy and milk protein, the plasma glucose concentration and average daily gain were not significantly different, on rations containing protected tallow, compared with the control ration. There was no significant difference between the soybean meal-protected tallow ration and the canola meal-protected tallow ration for any parameter measured except apparent digestibility of ether extract which was significantly higher for the canola meal-protected tallow ration (P<.01). / Land and Food Systems, Faculty of / Graduate
396

Childhood Obesity: Developing Early Nutrition & Feeding Education for Parents at Well Child Visits

Benson, Ashley Lynn January 2020 (has links)
Childhood obesity is an extensive problem in the United States and North Dakota (CDC, 2014). Significant health consequences are linked to obesity, including type two diabetes, hypertension, hyperlipidemia, cardiovascular disease, cancers, and psychological disorders (Pandita et al., 2016; Xu & Mishra, 2018). Obesity comorbidities, previously presented in later adulthood, now emerge in younger populations (Pandita et al., 2016). Unfortunately, treatment of obesity is not effective, and therefore, prevention must be the primary focus (Daniels et al., 2015; Pandita et al., 2016). Diet and eating behaviors have a significant impact on weight, and children develop taste preferences and lifelong eating behaviors within the first few years of life (Birch & Anzman, 2010; Daniels et al., 2015; IOM, 2011). Therefore, targeting interventions on feeding and nutrition in infancy may foster healthy habits for life and play a role in the prevention of obesity. Responsive feeding interventions hold promise in supporting healthy growth. Ellyn Satter’s Division of Responsibility promotes the responsive feeding relationship between parent and child. The purpose of the practice improvement project was to address childhood obesity prevention through the development of an educational curriculum on feeding and nutrition. The parent-focused education correlated with each well child visit (WCV) between the ages of two weeks and three years. A multidisciplinary team of representatives from pediatrics, behavioral health, and patient education was consulted to develop the education. Ten providers at Midwestern primary care clinics reviewed the educational curriculum and provided feedback on the content and methods to deliver the education to parents. Most providers found the content to be accurate (n = 7; 70%) and comprehensive (n = 8; 80%). Three providers suggested expanding on topics such as breastfeeding and mixing formula. Providers unanimously agreed that the curriculum is relevant and understandable. A formal literacy evaluation resulted in grade-level readability scores between the 6th and 8th-grade levels. Almost all providers (n = 9) believed the curriculum would be valuable for use in practice. The preferred delivery method chosen was one on one provider to parent education. The project clinic plans to pilot the curriculum with parents attending infant and toddler WCVs.
397

Assessing Resident Physician Knowledge about Breastfeeding Medicine in a Rural Family Medicine Clinic

Jensen, Samantha, Stoltz, Amanda 18 March 2021 (has links)
Title: Assessing Resident Physician Knowledge about Breastfeeding Medicine in a Rural Family Medicine Clinic Authors: Samantha Jensen, MD and Amanda Stoltz, MD, Bristol Family Medicine Residency Program, Department of Family Medicine, James H. Quillen College of Medicine, East Tennessee State University, Johnson City, TN Introduction: Many residents and faculty encourage the long-term goal of breastfeeding, and our residency program provides extensive training in obstetrics and newborn nursery. However, there is little structure and direct guidance for breastfeeding medicine already built in to the family medicine residency training. We aimed to develop a dedicated breastfeeding medicine longitudinal curriculum to improve the effectiveness of family medicine physician residents as teachers and advocates by improving residents’ fund of knowledge, provide structure for encouraging breastfeeding at prenatal visits, and incorporate breastfeeding into our family medicine practice by improving the on-site locations for breastfeeding and pumping. Method: The method of research was pre-lecture and post-lecture surveys comprised of 15 questions, including knowledge-based questions, assessment of confidence level, and a question on perceived barriers to breastfeeding. Participants attending two educational sessions during the study, and additional educational sessions have continued after study conclusion. The post-lecture survey was completed 12 weeks after first lecture. Lecture topics included an overview of breastfeeding medicine, how to encourage breastfeeding at prenatal appointments, contraindications, maternal nutritional supplements, formula supplementation, galatogogues, and the storage of breastmilk. Results: Results were compiled from the responses of 20 pretests and 9 posttest surveys. Results showed an increase in correct responses to the knowledge portion 61.15% pretest versus 77.69% posttest (t(28) 3.41, p<0.01). Resident physician confidence also increased by the conclusion of the study (t=28, p<.01). Conclusions: It can be concluded that educational lectures increase knowledge and confidence in resident physicians with regards to breastfeeding medicine. Areas for future study include specific research focusing on methods to increase access to resources for breastfeeding mothers.
398

Dieta da Raia-elétrica Narcine brasiliensis (Olfers, 1831) (Elasmobranchii : Narcinidae) na costa sul do Estado de São Paulo /

Laranjeira, Maria Eduarda Alves January 2020 (has links)
Orientador: Teodoro Vaske Junior / Resumo: A raia-elétrica N. brasiliensis ocorre do sudeste do Brasil ao norte da Argentina, apresenta de pequeno a médio porte e atinge comprimento máximo de 49 cm. Essas raias são geralmente encontradas em substrato lodoso, composto por areia fina, onde o movimento de protrusão da mandíbula é mais eficiente, facilitando também a sucção das presas. Exemplares de N. brasiliensis são capturados acidentalmente nas regiões sudeste e sul do Brasil, sendo muito suscetíveis às ações antrópicas predatórias. Apesar de ser uma espécie abundante ao longo da costa brasileira, há um conhecimento escasso sobre vários dos seus aspectos biológicos. Estudos relacionados a este gênero concentram-se em distribuição, reprodução, abundância das espécies e em sua dieta, a qual é composta principalmente por crustáceos e anelídeos marinhos, poríferos, equinodermos e sipunculas. O objetivo deste estudo consistiu em analisar o conteúdo estomacal de exemplares de N. brasiliensis, a fim de caracterizar sua dieta na costa sul do Estado de São Paulo, visando obter uma lista de itens alimentares identificados ao menor táxon possível e a proporção geral dos grandes grupos de presas de sua dieta; bem como avaliar a dieta em relação à ontogenia e sazonalidade, além de identificar os principais componentes anatômicos do trato digestório. A dieta de N. brasiliensis na região de estudo foi composta por cinco grandes grupos: Classe Polychaeta, Classe Sipunculida, Ordem Decapoda, Ordem Stomatopoda e Ordem Anguiliformes. Os... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The lesser electric ray N. brasiliensis is distributed from southern Brazil to northern Argentina, it is small to medium sized and its maximum lenght is 49 cm. These rays are usually found in muddy sediment, in which the jaws protusion movement is more efficient, making easier the prey suction. Specimens of N. brasiliensis are accidentally caught in the southeastern and southern regions of Brazil, being very susceptible to predatory anthropic actions. Although it is an abundant species along the Brazilian coast, there is no much information about its biological aspects. Studies related to the gender are focused in distribution, reproduction, species abundance and diet, which is mainly composed by crustaceans, polychaetes, poriferous, echinoderms and sipuncula. The objective of this research was to analyse the stomach content of N. brasiliensis specimens, to characterize its diet on the south coast of São Paulo State, aiming to obtain a list of food items identified at the lowest possible rate and the general proportion of the large groups of prey in their diet; as well as evaluating the diet in relation to ontogeny and seasonality, in addition to identify the main anatomical components of the digestive tract. The diet of N. brasiliensis in the study region was composed of five major groups: Class Polychaeta, Class Sipunculidea, Order Decapoda, Order Stomatopoda and Order Anguiliformes. Polychaetes 1, of the Arabellidae Family, were the main food component of this species in t... (Complete abstract click electronic access below) / Mestre
399

Comparison of Short Chain Volatile Fatty Acids in the Breastmilk of Normal and Overweight/Obese Mothers

Gaskill, Ellen R, Thomas, Kristy L, Wahlquist, Amy, Clark, W Andrew, Johnson, Michelle E 07 April 2022 (has links)
INTRODUCTION: Health professionals emphasize the importance of breastfeeding in the development of children up to 6-months of age. It is known that short chain volatile fatty acids (SCVFAs) are a byproduct of nutrient fermentation by gut microbiome. These SCVFAs interact with the gut/brain axis and are known to influence infant development. Therefore, a reflection of maternal gut microbiome could likely be found in breastmilk (BM) due to diffusion of SCVFAs across the gut wall into the blood. Previous research in our laboratory has shown differences in the SCVFA fecal fermentation profile between individuals with normal (N) versus overweight/obese (OWOB) body mass index (BMI). Therefore, our research question is: Is there a difference in the relative amount and diversity of SCVFAs in the BM of N compared to OWOB women? We hypothesized that women of N will have a more diverse SCVFA profile than OWOB women in their BM. METHODS: BM samples (200 ml) were collected from 44 women (22 N (BMI 22.0) and 22 OWOB (BMI 33.7) p2 while OWOB participants had a pre-gravid BMI of greater than 25.0 kg/m2. A 300 mg aliquot of lyophilized BM was placed in a separatory funnel with 5 ml of hexane and 5 ml of volatile fatty acid solution (VFA, (oxalic acid (0.1M/L), sodium azide (40mM/L))). The funnel was rocked back and forth 50 times and placed on a ring stand to rest for 10 minutes. The bottom phase of the solution was collected and freeze-dried. Five hundred µL of VFA solution was added to the samples to resuspend, centrifuged (4,000 x g) for 20 minutes, the supernatant was removed and transferred to a microcentrifuge tube then centrifuged (12,000 x g) for 15 minutes and decanted. Three hundred µL of supernatant was transferred to autoinjector vials fitted with a 350 µL insert and analyzed for SCVFAs via gas chromatography (GC) (Shimadzu) using a Phenomenex ZB-Wax Plus glass capillary column. RESULTS: SCVFAs acetate, propionate, isobutyrate, isovalerate and caproate were not different (p>0.10), while valerate (p< 0.02), isocaproate (pCONCLUSION:To our knowledge, this is the first time that SCVFAs have been quantified in the milk of lactating women using GC with an FID detector. This data supports the argument that the pre-gravid BMI of a mother can correlate to the SCVFA profile of her BM. It is unknown if the concentration observed in the mother’s BM in this study has an influence on the neonate’s gut/brain axis and neurological signals, however, we have demonstrated that the SCVFA profile is more diverse in the N BMI mother. Further research is warranted on the influence of maternal BM SCVFA composition on the growth and neurological development of her infant.
400

DAILY FEEDING PROCEDURE MODULATES IMPULSIVE CHOICE IN RODENT MODELS OF DECISION-MAKING

Tapp, Danielle N. 28 November 2018 (has links)
No description available.

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