A sustainable primary prevention strategy for infant iron deficiency anemia (IDA) was implemented and evaluated in a community with at-risk infants in northern Quebec, Canada. Communication strategies were used to promote iron-rich complementary food rather than iron-fortified formula, which can interfere with breastfeeding practice. This food-based approach has been successfully implemented in developing countries, but has not been applied in an industrialized country setting. / Mass media (i.e., radio dialogues, key messages, print material, point-of-purchase grocery store display) and interpersonal (i.e., homemade baby food cooking activity) communication strategies were developed in collaboration with community members and implemented in partnership with an existing community program. Reach and exposure of the strategies were measured using a questionnaire administered to a post-intervention sample (n = 45). Sales of promoted iron-rich infant food were examined pre- and post-intervention period. A repeat cross-sectional design was used for the impact evaluation. Two groups of mothers with infants, aged 7-10 months at Time 1 (n = 32) and Time 2 (n = 22) were interviewed. Outcome variables were infants' total iron and complementary food iron intakes measured by two 24-hour recalls. Secular trends in infants' hemoglobin values and milk type consumption were examined in the study community and two comparison communities. / Multiple communication channels increased awareness of IDA and influenced self-reported use of iron-rich infant food. Iron-rich infant food sales increased from pre- to post-intervention (p < 0.05). Complementary food intake iron increased between Time 1 (3.2 +/- 0.8 mg) and Time 2 (4.4 +/- 1.1 mg) (p < 0.05). The proportion of infants with anemia (hemoglobin < 110 g/L) significantly decreased from the period before (37.2%) to during (14.3%) the intervention (p < 0.05). No significant difference was found for this variable within the comparison communities. The proportion of infants receiving iron-fortified formula in the study community did not differ between Time 1 and Time 2, but increased from Time 1 (55%) to Time 2 (73%) (p < 0.05) in the comparison communities, indicating an erosion of breastfeeding practice. / These results suggest the effectiveness of communication strategies to improve infant iron nutrition in a community with good access to iron-rich infant food. The potential for this strategy in other communities warrants further investigation.

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Pelagic ecosystems are inherently complex in coastal inlets where they are controlled by physical processes and influenced by biogeochemical and foodweb interactions. Meteorological events are important drivers of this ecological variability. This thesis investigates their effect on the plankton dynamics of Lunenburg Bay, an inlet on the Atlantic coast of Nova Scotia (Canada). In this region, meteorological events are dominated by upwelling in summer, which are a dominant source of flushing and nutrient variability for the inlets. Despite these events, which induce phytoplankton blooms in other regions, the concentration of phytoplankton as chlorophyll remains relatively low throughout the summer in Lunenburg Bay. To reveal the underlying processes limiting the development of phytoplankton biomass, and therefore to improve our understanding of the factors regulating plankton dynamics in this inlet, the objectives of this thesis are to determine the main drivers of variability in phytoplankton biomass and plankton community structure, and to identify the factors limiting the development of phytoplankton biomass in Lunenburg Bay. For that, I use a dataset collected at a coastal observatory located in Lunenburg Bay that covers the years 2003–2006, complemented by a series of transects carried out in summer 2006. The dataset covers physical, chemical and biological properties of the bay, including plankton taxonomy. Two types of physical-biological coupled models are developed: a low-resolution box model of Lunenburg Bay with steady-state wind forcing, and a high-resolution nested model of Lunenburg Bay using the Regional Ocean Modelling System (ROMS) to hindcast a series of upwelling events in 2006. The results reveal that four factors regulate the phytoplankton response to upwelling events in Lunenburg Bay, namely (1) the duration of an upwelling event, (2) the low nitrate concentration in source waters, (3) the flushing rate of the inlet (hence transport), and (4) the bathymetry along the inshore-offshore axis of the bay. In addition, (5) the occurrence of upwelling and (6) the inshore-offshore gradient of increasing depth influence the structure of respectively phytoplankton and zooplankton communities, indicating a dissimilarity in the processes structuring plankton communities in the lower food web. A conceptual model is then developed to describe the role of transport and nitrate concentration in source waters in controlling plankton dynamics in an inlet.

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The seasonal asymmetry in coastal temperatures on Hudson Bay was explored and evaluated as a proxy to hindcast sea ice conditions prior to 1972. Various indices of air temperature difference (∆T) between Churchill, MB and Inukjuak, QC were tested for linear correlations with spatially averaged sea ice concentration (SIC) and ice-free season length (IFS). A multiple regression equation employing a 31-day average of peak ∆T and a 61-day average of temperature during freeze-up reproduced the IFS record with an average error of 8.1 days. This equation was employed to extend the IFS record by 28 years. The resulting 68-year time series revealed a significant increasing trend most pronounced from 1985 to 2011. Hindcast data helped eliminate low-frequency climate oscillations of periodicity <68 years as a source of this trend, lending further evidence to the growing consensus of a declining sea ice being the result of anthropogenic climate forcing.

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Gestational diabetes mellitus (GDM) and infant macrosomia are important obstetric health concerns for Aboriginal populations in Canada. Previous research in non-Aboriginal populations has established that GDM and macrosomia are associated with increased risk of fetal morbidity. Specifically, GDM is a risk factor for infant macrosomia, hypoglycemia, polycythemia, hypocalcemia, and hyperbilirubinemia. Furthermore, macrosomia is an independent risk factor for shoulder dystocia, clavicular fracture, brachial plexus injury, birth asphyxia and operative delivery. The main objectives of this study were to determine prevalence rates of GDM and macrosomia related neonatal complications for the James Bay Cree population of northern Quebec, and to identify risk factors for specific birth trauma injuries and metabolic complications in the population. The prevalence of macrosomia (≥4500 g) was 10.4%, and the estimated prevalence of GDM was 16.6% (95% CI 14.6-18.6) (n = 229/1379). Shoulder dystocia was the most common birth trauma event among the Cree, affecting 2.5% (n = 42/1650) of all Cree births, and 9.3% (n = 16/172) of macrosomic deliveries ≥4500 g. The prevalence of neonatal hypoglycemia was also high, affecting 8.8% (n = 144/1650) of all Cree newborns, and 18.1% (n = 34/192) of GDM deliveries. Macrosomia (BW ≥ 4500 g) was a significant risk factor for shoulder dystocia, clavicular fracture, hypoglycemia, and caesarean section delivery. After adjusting for maternal age, parity, and gestational age, GDM was identified as a significant risk factor for macrosomia (≥4500 g), hypoglycemia, polycythemia, and hypocalcemia. In summary, this study identified a high incidence of neonatal complications among the James Bay Cree compared with rates in the general North American population. These outcomes can be explained, in part, by high prevalence rates of gestational diabetes and infant macrosomia. Further studies to investigate the long-term consequences of GDM and

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The objectives of this research were to determine the prevalence of anemia, and identify risk factors for anemia, in 9-month-old Cree infants living in northern Quebec. The prevalence of anemia (hemoglobin <110 g/L) was 25--32%, depending on the study sample. Iron deficiency was present in 28.2% of infants who could be classified and 14.4% had iron deficiency anemia. Fewer than 2% of infants had low birth weight (<2500 g) so most infants should have been born with adequate iron stores. One cause of anemia that was identified was a diet that was low in iron. Only 15.1% of infants were reported by guardians to eat meat daily and 28.5% were reported to never eat meat. Infants who were breastfed or cow's milk fed did not obtain sufficient iron for effective erythropoiesis. Compared with formula that was predominantly iron fortified, the odds ratio (OR) for anemia was 7.9 (95% CI 3.4--18.2) for breast milk and 5.0 (95% CI 2.0--12.7) for cow's milk. When milk type was controlled for, weight gain since birth was significantly associated with microcytic erythrocytes (OR comparing the highest tertile of weight gain to the lowest tertile 2.9, 95% CI 1.2--6.6). This indicates that fast-growing infants were not meeting their iron needs for growth. Another risk factor for anemia that was identified was common childhood infections. The prevalence of anemia among infants reported as recently unwell with an infection was higher than among infants reported as recently well (31.1% vs. 19.0%, chi2 = 4.27, p = 0.039). The prevalence of elevated blood lead was 2.7% and is not a major public health problem. No evidence for vitamin A deficiency was found. Serum retinol was positively associated with all iron status indicators. Cree infants who were given supplements containing vitamin A had a lower prevalence of anemia (hemoglobin <105 g/L) (10.8% vs 23.2%, chi2 = 5.97, p = 0.015). These results suggest a role for vitamin A in iron metabolism. To prevent anemia in aboriginal i

No description available.