The potential of community fish refuges (CFRs) in rice field agro-ecosystems for improving food and nutrition security in the Tonle Sap region

The fisheries sector in Cambodia contributes 8%–12% to national GDP and 25% - 30% to agricultural GDP, with an estimated 4.5 million people involved in fishing and associated trades. Fish and other aquatic animals are important food sources, contributing an estimated national average of 60% - 70% of total animal protein intake. Of the 2013 total fish production, 550,000 metric tons were harvested from freshwater habitats, of which rice field fisheries and small-scale family fisheries contributed approximately 20%. The productivity and value of rice field fisheries to households in rural Cambodia has been highlighted in a number of previous studies. The Fisheries Administration of the Ministry of Agriculture, Forestry and Fisheries plans to increase productivity from rice field fisheries and aquaculture at an annual rate of 15% to maintain supply for a growing population. This report draws mainly on the baseline and monitoring data from the Rice Field Fisheries Enhancement Project (RFFEP) during its implementation between 2012 and 2014. Reference is also made to the Fish on Farms project to highlight the relative contribution of fish from small-scale aquaculture compared to wild-caught fish.

Nutrition or Detoxification: Why Bats Visit Mineral Licks of the Amazonian Rainforest

Many animals in the tropics of Africa, Asia and South America regularly visit so-called salt or mineral licks to consume clay or drink clay-saturated water. Whether this behavior is used to supplement diets with locally limited nutrients or to buffer the effects of toxic secondary plant compounds remains unclear. In the Amazonian rainforest, pregnant and lactating bats are frequently observed and captured at mineral licks. We measured the nitrogen isotope ratio in wing tissue of omnivorous short-tailed fruit bats, Carollia perspicillata, and in an obligate fruit-eating bat, Artibeus obscurus, captured at mineral licks and at control sites in the rainforest. Carollia perspicillata with a plant-dominated diet were more often captured at mineral licks than individuals with an insect-dominated diet, although insects were more mineral depleted than fruits. In contrast, nitrogen isotope ratios of A. obscurus did not differ between individuals captured at mineral lick versus control sites. We conclude that pregnant and lactating fruit-eating bats do not visit mineral licks principally for minerals, but instead to buffer the effects of secondary plant compounds that they ingest in large quantities during periods of high energy demand. These findings have potential implications for the role of mineral licks for mammals in general, including humans.

Early nutrition and eczema in infancy

Eczema prevalence rates among Irish infants are unreported, despite eczema being the most common inflammatory condition of infancy. Maternal and infant nutritional status including vitamin D and other fat-soluble vitamins as well as early infant feeding have been linked with eczema initiation and development. Therefore, early nutrition could be a potential modifiable risk factor. The objective of this thesis was to prospectively describe early infant feeding and complementary feeding practices, to evaluate infant vitamin D supplementation practice, to quantify cord serum 25-hydroxyvitamin D [25(OH)D] and propose reference intervals for vitamin D metabolites, to report eczema prevalence and explore the potential role of infant nutrition and eczema. These research needs were investigated through the Cork BASELINE (Babies After SCOPE: Evaluating the Longitudinal Impact with Neurological and Nutritional Endpoints) Birth Cohort Study (n 2137). This thesis was the first comprehensive report from the birth cohort, therefore it was important to describe the cohort sociodemographic profile. Although socio-demographic characteristics compared well with national data, there was an over-representation of educated mothers which may limit the generalizability of the results. From August 2008 through November 2011, comprehensive postnatal assessments were completed at day 2 and at 2, 6, 12 and 24 months. Breastfeeding rates were low, while complementary feeding practices were broadly compliant with national guidelines. The implementation of a national infant vitamin D supplementation policy had a major impact on supplementation practice. Low levels of serum 25(OH)D were universal among Irish neonates. Eczema is a complex and multifaceted disease, which is increasing globally. This was the first report of eczema prevalence data among Irish infants which compared with international reports. Given the high prevalence and considerable burden eczema has on the lives of sufferers, intensive research efforts to identify a cause and therapeutic strategies to prevent/reduce eczema was re-emphasized in this thesis.

Nutrition, growth and body composition in infancy

This thesis is presented in two parts. Data for this research is from the Cork BASELINE (Babies after SCOPE, Evaluating Longitudinal Impact using Neurological and Nutritional Endpoints) Birth Cohort Study (n = 2137). In this prospective birth cohort study, pediatric follow-up with in-person appointments were repeated from the time of birth through to 2, 6 and 12 months, and at 2 years. Body composition was measured by air displacement plethysmography at birth and at 2 months using the PEA POD Infant Body Composition Tracking System. This thesis provides the first extensive report on the study’s 2 year assessment. In part one, the aims were to investigate potential early-life risk factors for childhood overweight and obesity, including rapid growth and body composition in infancy and umbilical cord concentrations of leptin and high molecular weight (HMW) adiponectin. This research is the first to describe rapid growth in early infancy in terms of changes in direct measures of body composition. These are also the first data to examine associations between umbilical cord leptin and HMW adiponectin concentrations and changes in fat and lean mass in early infancy. These data provide additional insight into characterising the growth trajectory in infancy and into the role of perinatal factors in determining infant growth and subsequent overweight/obesity risk. In part two of this thesis, the aims were to quantify vitamin D intake and status at 2 years and to investigate whether 25-hydroxyvitamin D [25(OH)D] concentrations in early pregnancy and in umbilical cord blood are associated with infant growth and body composition. There was a low prevalence of vitamin D deficiency among Irish 2 year olds (n = 742) despite a high prevalence of inadequate intakes and high latitude (51°N). Maternal 25(OH)D concentrations at 15 weeks gestation and cord 25(OH)D concentrations at delivery were not associated with infant growth or adiposity.

Polymeric and monomeric IgA response in serum and milk after parenteral cholera and oral typhoid vaccination

SCOPUS: ar.j

A polymeric IgA response in serum can be produced by parenteral immunization

SCOPUS: ar.j

Mycobacteriosis in Chesapeake Bay Striped Bass (Morone saxatilis): The Interaction of Nutrition and Disease

Field and laboratory studies were conducted from 1998 - 2005 to examine the relationship between nutritional status and mycobacteriosis in Chesapeake Bay striped bass (Morone saxatilis). A review of DNA from archived tissue blocks indicated that the disease has been present since at least 1984. Field surveys and feeding trials were conducted from 1998-1999 to determine the nutritional condition of striped bass and the association with disease state. Proximate composition revealed elevated moisture (~ 80%) and low storage lipids (< 0.5% ww), characteristic of a poorly nourished population. These findings were not consistent with data collected in 1990-1991, or with experimentally fed fish. Mycobacteriosis explained little of the variance in chemical composition (p > 0.2); however elevated moisture and low lipid concentration were associated with fish with ulcerative lesions (p < 0.05). This suggests that age 3 and 4 striped bass were in poor nutritional health in 1998-1999, which may be independent from the disease process. Challenge studies were performed to address the hypothesis that disease progression and severity may be altered by nutritional status of the host. Intraperitoneal inoculation of 104 CFU M. marinum resulted in high mortality, elevated bacterial density, and poor granuloma formation in low ration (0.15% bw/d) groups while adequately fed fish (1% bw/d) followed a normal course of granulomatous inflammation with low mortality to a steady, equilibrium state. Further, we demonstrated that an active inflammatory state could be reactivated in fish through reductions in total diet. The energetic demand of mycobacteriosis, was insignificant in comparison to sham inoculated controls in adequately fed fish (p > 0.05). Declines in total body energy were only apparent during active, inflammatory stages of disease. Overall, these findings suggest that: 1) mycobacteriosis is not a new disease of Chesapeake Bay striped bass, 2) the disease has little energetic demand in the normal, chronic progression, and 3) poor nutritional health can greatly enhance the progression and severity, and reactivation of disease. The implications of this research are that management strategies focused on enhancing the nutritional state of striped bass could potentially alter the disease dynamics in Chesapeake Bay.

Leptin metabolically licenses T cells for activation to link nutrition and immunity.

Immune responses are highly energy-dependent processes. Activated T cells increase glucose uptake and aerobic glycolysis to survive and function. Malnutrition and starvation limit nutrients and are associated with immune deficiency and increased susceptibility to infection. Although it is clear that immunity is suppressed in times of nutrient stress, mechanisms that link systemic nutrition to T cell function are poorly understood. We show in this study that fasting leads to persistent defects in T cell activation and metabolism, as T cells from fasted animals had low glucose uptake and decreased ability to produce inflammatory cytokines, even when stimulated in nutrient-rich media. To explore the mechanism of this long-lasting T cell metabolic defect, we examined leptin, an adipokine reduced in fasting that regulates systemic metabolism and promotes effector T cell function. We show that leptin is essential for activated T cells to upregulate glucose uptake and metabolism. This effect was cell intrinsic and specific to activated effector T cells, as naive T cells and regulatory T cells did not require leptin for metabolic regulation. Importantly, either leptin addition to cultured T cells from fasted animals or leptin injections to fasting animals was sufficient to rescue both T cell metabolic and functional defects. Leptin-mediated metabolic regulation was critical, as transgenic expression of the glucose transporter Glut1 rescued cytokine production of T cells from fasted mice. Together, these data demonstrate that induction of T cell metabolism upon activation is dependent on systemic nutritional status, and leptin links adipocytes to metabolically license activated T cells in states of nutritional sufficiency.

Federal Nutrition Assistance at Farmers’ Markets: Evaluating Self-Efficacy and the Home Nutrition Environment

SNAP and WIC help alleviate food insecurity among low-income families; however, some still struggle with fruit and vegetable accessibility. Farmers' markets present the opportunity to purchase fresher foods than other food retailers; therefore, we chose this environment to conduct our research. A survey of 70 WIC/SNAP shoppers at three D.C. metropolitan area farmers' markets assessed the correlation between parental self-efficacy and the home nutrition environment (composed of family health behavior, perceived barriers, and fruit and vegetable offerings in the home) and found a significant relationship. Interviews were used to evaluate market accessibility, SNAP/WIC benefit redemption, and the feasibility of accepting these benefits. Both market participants and coordinators mentioned the greater variety and superior quality of farmers' market produce but also suggested several improvements. Findings suggest that SNAP incentive programs may increase fruit and vegetable purchases. Programs targeting consumer self efficacy may also produce positive outcomes.