Antibiotics are added to animal feeds as prophylactic agents and to encourage weight gain in livestock. However, there is concern that the widespread use of antibiotics in animal agriculture encourages for the selection of resistance genes and has contributed to the rise of multiply antibiotic resistant strains of pathogenic bacteria. For this reason, there is interest in quantifying antibiotics in environmental samples. The determination of three antibiotics in swine waste, namely chlortetracycline, tetracycline and oxytetracycline, using LC-MS with electrospray ionization is presented here in. Antibiotics from swine waste were quantified across the lifespan of the swine. Trends were present in each of the four life stages (gestation, farrowing, nursery, and finishing). The nursery stage of life presented the most dominate concentrations and the most consistent trend in antibiotic concentrations.

Health promotion identifies health as a resource for daily living and emphasizes the reciprocal relationship between people and their environments in creating health (MacDonald, 2002). In this thesis. I explore how community gardening programs can be used to improve the health and well being of vulnerable populations by creating positive changes within their physical and social environments. Furthermore, I address how community gardens can educate and empower these populations to live healthier lifestyles. My research is based on the creation and exploration of a project in Victoria. BC, where homeowners share their backyard vegetable gardens with volunteer gardeners. It is a small-scale qualitative study in the tradition of ethnographic research where the aim is to enhance understanding of phenomena (Johnston, Gregory, Pratt, & Watts. 2000. p. 238). I facilitated the project and monitored the progress of three garden partnerships for six months during Victoria's long growing season in 2005. Using in-depth interviews and participant observation techniques. I was able to come to a deeper understanding of the participants' experience of the project. This thesis addresses how the project may have promoted their health and well-being with specific reference to physical, psychological and social health and well-being. Suggestions for improvements for future application of the project are also provided.

Intensive methods for the mass production of Oreochromis niloticus (Chitralada strain) seed using concrete tanks, hapas within earthen ponds and earthen ponds were investigated. On the basis of these trials, the productivity and economic performance of various production strategies for hormonally sex-reversed Oreochromis fry (MT fry) were then compared and modelled for adoption in Central and Northeast Thailand. Regular disturbance and harvesting of seed after a short period of spawning opportunity (5-10 days) was found to increase seed production in concrete spawning tanks. Exchange of female broodfish increased synchrony of breeding. A change in conditioning and spawning environment had no effect on seed yield from spawning tanks and hapas (area =12.57 m2and 40m2 respectively). Seed wet weight, seed clutch size and weight was greater in female fish spawned in tanks than hapas. Females conditioned in hapas however produced heavier seed clutches of larger absolute and relative size than tank conditioned fish. Records of tagged females indicated considerable differences in the frequency of spawning; in hapas the distribution was normal wheras in tanks it was skewed. The evidence suggests that hierarchy is important in the control of reproduction and exerts it's strongest effect in clear water, densely stocked tanks. Selective female broodfish exchange optimised seed yield per unit weight of broodfish and seed production was not improved by conditioning females for periods longer than 10 days. Male broodfish exchange did not significantly improve (P > 0.05) seed yields. Early nutrition of broodfish raised under different supplemental feeding regimes in fertilised earthen ponds had a significant effect on later spawning frequency in concrete tanks. However, this effect was confined to broodfish maintained at densities lower or higher than optimal for seed production. Broodfish stocked over a range of densities for extended periods (201 days) showed greater variability of seed production in hapa than tank production systems. This was mainly due to periods of poor water quality in hapas; when water quality was high seed production was significantly higher in hapas than tanks over a range of broodfish densities. The optimal density of broodfish for seed production was exceeded in tanks but not hapas. The relationship between seed production and broodfish density over time suggested that both stocking biomass and number have an effect on fry output. Density of broodfish showed an inverse relationship to clutch size in both tanks and hapas and synchrony of spawning in tanks. Production of swim-up fry in large earthen ponds (area=1740m2) was not significantly different (P>0.05) at 2 levels of harvest intensity. The use of small broodfish however produced double the yield of hormone treatable fry than a similar biomass of larger broodfish of the same cohort. A commercial scale incubation system was devised and evaluated in order to allow tank and hapa systems harvesting unhatched seed to be compared with the production of swim-up fry obtained from earthen ponds. Seed removed from mouthbrooding females was roughly staged and incubated in batches of similar development to give information on survival to swim-up fry. A simple incubation system was designed with a capacity for hatching >100,000 eggs/set. A mean survival of 75% of all harvested seed to swim-up fry was obtained over several trials. A trend to intensification (fry/mVday) from ponds to hapas to tanks was evident when yields of swim-up fry are compared. Productivity exceeded any in the published literature for comparable systems, largely because of the intensity of broodstock management and early and efficient harvest of seed. Broodfish productivities (fry/kg female/month) were also higher across the range of systems tested often by a factor of 1.5-3. The best strategies were selected over a range of total investment cost using dominance analysis. Economic analysis suggested that for a start-up operation in Central Thailand fry production in earthen ponds can give the best return on levels of investment of less than Baht 0.8 million. Substitution of techniques into current carp fry production operations in Northeast Thailand indicated that more intensive methods (production in tanks and hapas) are more attractive over a range of investment levels. The break-even price of MT fry after hormone treatment in nylon hapas was approximately half the cost of treatment in a recirculated water concrete tank system. The break-even price in Central Thailand was lower than the Northeast by a factor of around 1.5 but the break-even price for both areas was lower than the current price of untreated Oreochromis fry.

Research on the putative health benefits has indicated that kefir, a traditional fermented milk, might have antimutagenic and antitumor properties. The major objective of the present thesis was to isolate and identify antitumor compounds in cow's milk kefir and investigate the possible mechanisms involved. High speed centrifugation (HSC), molecular weight cut-off filtration (MWCO), size exclusion high performance liquid chromatography (SEC-HPLC) and reverse phase-HPLC (RP-HPLC) were utilized for fractionation of kefir and a cell culture model was developed to screen for the antiproliferative effects of the kefir fractions. The antiproliferative effects of bacteria-free extracts from different fermentation stages of kefir production, as well as bacteria-free extracts from milk and yogurt were compared. The results showed that extracts from an early stage of fermentation (i.e., kefir mother culture) and the final commercial kefir product both exerted dose-dependent inhibition effects on human mammary tumor MCF-7 cells, yogurt extracts showed less potent antiproliferative effects, while pasteurized milk extracts showed no antiproliferative effects. No antiproliferative effects of the kefir extracts were observed on human mammary epithelial cells (HMEC) whereas the yogurt extracts showed antiproliferative action in HMEC cells at a high dose. A fraction of the kefir mother culture isolated by HSC, MWCO and RP-HPLC contained components that inhibited MCF-7 cell growth and had no effect on HMEC cells. Characterization of the bioactive fraction using mass spectrometry (MS) indicated that the main components in the fraction are likely fragments of kefiran and/or ceramide containing compounds such as gangliosides. The growth inhibitory effect may be mainly caused by the induction of TNF-alpha in MCF-7 cells. Whole extracts of kefir depleted glutathione (GSH) in MCF-7 cells, while the SEC-HPLC Fraction 7 and the RP-HPLC Fraction 30 induced GSH produc

The prevalence of sub-clinical vitamin A deficiency (VAD) and anemia of lactating women (n = 113) and their breastfed infants aged 1--6 months was measured among a peri-urbanite South African sample. Mother's mean hemoglobin (Hb) was 12.4 +/- 1.3 g/dL with 32% anemia (Hb < 12g/dL). Retinol in serum was 49.8 +/- 13.2 mug/dL and 66.0 mug/dL (median) in breast milk; no evidence of sub-clinical VAD. Infants, 62% &le; 3 months, had mean Hb of 10.9 +/- 1.1 g/dL (with anemia present (<11g/dL), in 50%). Mean infant serum retinol was 26.9 +/- 7.2 mug/dL (10% prevalence of marginal VAD). No infants were exclusively breastfed. Weaning foods and breast milk substitutes were introduced early and infant intake of traditional medicines was common (52%). Our data suggest that anemia was present in both mothers and infants while VAD was evident only in infants. This early occurrence of micronutrient deficiencies may be attributed to less than optimal breastfeeding practices.

The purpose of this grounded theory study was two-fold; first, to explore how mothers develop an understanding of childhood immunization which contributes to the decision¬making process resulting in a decision not to participate in immunization. Second, the perceptions of childhood immunization of health care professionals were also examined. The understanding and decision-making process of eight mothers was compared with the perceptions of twelve health care professionals. A number of themes were constructed from the research and a grounded theory was developed which emphasizes the importance of collaboration between non-immunizing mothers and health care professionals to promote positive health outcomes in children. The findings will assist health care professionals in understanding the factors contributing to the immunization decision-making process, which will subsequently support in delivering immunization programs. Recommendations to promote support and respect for parents' decision not to immunize their children, and assist in educating parents on immunization are also included. / xiii, 275 leaves ; 29 cm

The main goal of this study was to evaluate the utility of physical activity (PA) measurement in an Inuit population with a self-administered questionnaire. The objective was to validate a culturally relevant physical activity questionnaire that measures Inuit PA levels. To do this, the International Physical Activity Questionnaire (IPAQ) was evaluated against the Caltrac accelerometer and anthropometric/physiologic measurements. / There were a number of compliance problems encountered when implementing the Caltrac in the pilot community which resulted in too few Caltrac scores available for analyses. However, IPAQ PA score (N=44) was significantly inversely related to Body Mass Index (p≤0.05) and positively related to high-density lipoprotein cholesterol (p≤0.03). / The results indicate that the IPAQ has potential but needs further refinements to be acceptable to Inuit populations and needs re-evaluation in a larger sample. The participants found it very difficult to remember the time spent performing each activity and, in general, the IPAQ was not well received.

Medium chain triglycerides (MCT) have long been advocated as potential weight-lowering agents or potential tools in the treatment and prevention of human obesity. These statements have been made after findings from human and animal trials that consumption of MCT increases energy expenditure and fat oxidation compared to long chain triglycerides (LCT). In addition, animal studies have resulted in lower body weight gain and smaller fat depots when animals were fed MCT compared to those fed LCT. However, long-term controlled trials studying the effects of consumption of MCT in humans have not been conducted and the longest trial to date, 14 d of duration, has shown that the effect of MCT on energy expenditure may be transient. Therefore, we aimed to determine whether, in controlled feeding conditions, consumption of MCT for 4 wk would lead to differences in energy expenditure and substrate oxidation versus consumption of an isocaloric diet rich in LCT. Furthermore, our aim was to establish whether consumption of MCT for 4 wk would lead to greater changes in body composition than would LCT consumption. We conducted two randomized, controlled, crossover feeding trials involving overweight women and men to test our objectives. A secondary objective was to examine the potential satiating effect of MCT, and this was tested in men. Finally, a third objective was to determine whether, when combined with phytosterols and flaxseed oil, MCT consumption would result in different blood lipid profile compared to LCT. Nineteen healthy overweight women and 24 healthy overweight men participated in two separate randomized controlled trials to test these objectives. Energy expenditure and body composition were assessed at the beginning and end of each experimental phases, which differed only in the type of fat included in the controlled diets. Blood samples were also taken at baseline and endpoint of each phase to determine plasma lipid concentrations. Result

Graduation date: 2000

According to literature, particularly from data obtained from the World Health Organisation, physical inactivity or sedentarism is one of the leading causes of the major non-communicable diseases, which contributes substantially to the global burden of diseases, death and disability. The burden of mortality, morbidity and disability attributable to non-communicable diseases is currently greatest and is continuing to grow in the developing countries. Most declines in physical activity are during the transition from high school to college or university. The aim of the study was to ascertain perceptions of physical activity, specifically / perceived benefits of, perceived barriers and perceived helpful motivational factors to physical activity among tertiary institution students in Rwanda, and to find out whether demographic and background characteristics have an influence on these perceptions.