Healthy chickens, healthy children? Exploring contributions of village poultry-keeping to the diets and growth of young children in rural Tanzania

One in three Tanzanian children under five years of age is affected by stunting: an outcome of chronic undernutrition and an indication of impaired physical and cognitive development. The potential for livestock-keeping to contribute positively to children’s growth, including by providing nutrient-dense animal-source foods and household income to enable other nutritious food purchases, has been well-described but poorly demonstrated. Village chickens are an accessible and versatile form of livestock, kept in small free-ranging flocks by many households in resource-poor settings and often managed by women. This mixed methods research was undertaken in villages of Manyoni District in central Tanzania, alongside a project establishing a community-based vaccination service against Newcastle disease in village chickens. Significantly larger chicken flock sizes were identified as an outcome of vaccinating in a given campaign and of continuing to vaccinate at four-monthly intervals, compared to vaccinating less often or not at all. Chicken meat and eggs were infrequently eaten during the study period, with eggs more commonly hatched to increase chicken numbers and chickens retained for sale in times of need. Consumption of poultry products by mothers and their young children was closely linked and no gender-based differences in children’s consumption frequency were found. Analysis of national and regional food composition tables highlighted the need for recent and locally-derived data on the nutrient content of animal-source foods, to better reflect the products of indigenous livestock in low-input management systems. This thesis did not identify a significant impact of chicken-keeping on the height-for-age of children over a two-year period; however, importantly, it found no negative health or growth impacts which would undermine a continued focus on poultry interventions as a strategy to sustainably enhance nutrition at a household level

Evaluating pictorial charts as a means of collecting participant-recorded data on household dietary diversity in low-literacy communities in Tanzania

Innovative methods to collect dietary data at multiple times across the year are needed to better understand seasonal or temporal changes in household diets and measure the impact of nutrition-sensitive agricultural programmes in low-income countries. The present study aims to validate a picture-based research tool for participants to self-record their household’s dietary diversity each month in villages of Manyoni District, Tanzania. Pictorial record charts were developed to reflect local food resources. In 113 randomly selected households, the person responsible for food preparation was trained to mark all items consumed by any household member within the home, or prepared for consumption outside the home, for a single recording day. The next day, an interview-based household 24-h food recall (H24HR) was collected for the same period. Separate analyses tested agreement (a) between picture charts and H24HR and (b) between H24HR following chart completion and on an alternative day. Concordance between methods differed between food groups and items but was high to very high for all cereals, vegetables, pulses, legumes and nuts and almost all fruits. Recording of ten items (including non-cultivated fruits and ingredients of mixed dishes) differed significantly between H24HR assessments, all of which were reported by more households in interviews following chart completion. Results suggest potential for visual prompts and the contemporaneous nature of data collection to improve the accuracy of interview-based recall. With adequate investment in developing and implementing context-adapted tools, pictorial charts may also offer an effective standalone method for use at multiple time-points in agricultural programme

High yield production of 1,4-cyclohexanediol and 1,4-cyclohexanediamine from high molecular-weight lignin oil

The complete utilization of all lignin depolymerization streams obtained from the reductive catalytic fractionation (RCF) of woody biomass into high-value-added compounds is a timely and challenging objective. Here, we present a catalytic methodology to transform beech lignin-derived dimers and oligomers (DO) into well-defined 1,4-cyclohexanediol and 1,4-cyclohexanediamine. The latter two compounds have vast industrial relevance as monomers for polymer synthesis as well as pharmaceutical building blocks. The proposed two-step catalytic sequence involves the use of the commercially available RANEY® Ni catalyst. Therefore, the first step involves the efficient defunctionalization of lignin-derived 2,6-dimethoxybenzoquinone (DMBQ) into 1,4-cyclohexanediol (14CHDO) in 86.5% molar yield, representing a 10.7 wt% yield calculated on a DO weight basis. The second step concerns the highly selective amination of 1,4-cyclohexanediol with ammonia to give 1,4-cyclohexanediamine (14CHDA) in near quantitative yield. The ability to use RANEY® Ni and ammonia in this process holds great potential for future industrial synthesis of 1,4-cyclohexanediamine from renewable resources

Characterising infant and young child feeding practices and the consumption of poultry products in rural Tanzania: A mixed methods approach

Suboptimal breastfeeding practices, early initiation of complementary feeding, and monotonous cereal‐based diets have been implicated as contributors to continuing high rates of child undernutrition in sub‐Saharan Africa. Nutrition‐sensitive interventions, including agricultural programs that increase access to nutrient‐rich vegetables, legumes, and animal‐source foods, have the potential to achieve sustainable improvements in children's diets. In the quest to evaluate the efficacy of such programs in improving growth and development in the first 2 years of life, there is a role for mixed methods research to better understand existing infant and young child feeding practices. This analysis forms part of a longitudinal study assessing the impact of improvements to poultry health and crop production on diets and growth of 503 randomly selected children from eight rural communities in Manyoni District in central Tanzania. Using an explanatory sequential design, the quantitative phase of data collection was conducted between May 2014 and May 2016, comprising six monthly structured questionnaires, four monthly household‐level documentation of chicken and egg consumption, and fortnightly records of children's breastfeeding status. The subsequent qualitative phase involved in‐depth interviews with a subset of 39 mothers in October 2016. Breastfeeding was almost universal (96.8%) and of long duration (mean = 21.7 months, SD = 3.6), but early initiation of complementary feeding was also common (74.4%; mean = 4.0 months, SD = 1.8), overwhelmingly driven by maternal perceptions of insufficient milk supply (95.0%). Chicken and eggs were infrequently eaten, but close associations between maternal and child consumption patterns (p < .001) suggest the potential for strategies that increase household‐level consumption to bring nutritional benefits to young children

Exploring the complementarity of fortification and dietary diversification to combat micronutrient deficiencies: a scoping review

Achieving a balanced and diverse diet remains a challenge for many people, contributing to an ongoing burden of micronutrient deficiencies, particularly in low-income settings. Fortification or dietary diversification are common food-based approaches. We conducted a scoping review to: 1) find evidence on whether combined food–based strategies are more effective than single strategies, and 2) understand how strategies implemented together could complement each other to achieve optimal nutritional impact on populations. Peer-reviewed articles selected (n = 21) included interventions or observational studies (n = 13) and reviews (n = 8). We found little evidence of an added nutritional impact. On the other hand, it is apparent that fortification and dietary diversification target different types of settings (urban compared with rural) and foods (that is, low priced compared with highly priced). Further research is needed to understand the complementarity of these approaches and establish evidence of the effectiveness of combined strategies to foster policy adoption

The GMRT EoR Experiment: Limits on Polarized Sky Brightness at 150 MHz

The GMRT reionization effort aims to map out the large scale structure of the Universe during the epoch of reionization (EoR). Removal of polarized Galactic emission is a difficult part of any 21 cm EoR program, and we present new upper limits to diffuse polarized foregrounds at 150 MHz. We find no high significance evidence of polarized emission in our observed field at mid galactic latitude (J2000 08h26m+26). We find an upper limit on the 2-dimensional angular power spectrum of diffuse polarized foregrounds of [l^2 C_l/(2 PI)]^{1/2}< 3K in frequency bins of width 1 MHz at 300<l<1000. The 3-dimensional power spectrum of polarized emission, which is most directly relevant to EoR observations, is [k^3 P_p(k)/(2 PI^2)]^{1/2} 0.03 h/Mpc, k < 0.1 h/Mpc. This can be compared to the expected EoR signal in total intensity of [k^3 P(k)/ (2 PI^2) ]^{1/2} ~ 10 mK. We find polarized structure is substantially weaker than suggested by extrapolation from higher frequency observations, so the new low upper limits reported here reduce the anticipated impact of these foregrounds on EoR experiments. We discuss Faraday beam and depth depolarization models and compare predictions of these models to our data. We report on a new technique for polarization calibration using pulsars, as well as a new technique to remove broadband radio frequency interference. Our data indicate that, on the edges of the main beam at GMRT, polarization squint creates ~ 3% leakage of unpolarized power into polarized maps at zero rotation measure. Ionospheric rotation was largely stable during these solar minimum night time observations.Comment: 17 pages, 6 figures, 2 tables; changed figures, added appendices. To appear in MNRA

Fish acquisition and consumption in the African Great Lakes Region through a food environment lens: A scoping review

Effective actions for the fishery and aquaculture sectors to contribute toward improving nutrition rely on an understanding of the factors influencing fish intake, particularly amongst vulnerable populations. This scoping review synthesises evidence from 33 studies in the African Great Lakes Region to examine the influence of food environments on fish acquisition and consumption. We identified only two studies that explicitly applied a food environment framework and none that linked policy conditions with the contribution of fish to diets. Economic access to fish was represented in the largest number of included studies (21 studies), followed by preferences, acceptability and desirability of fish (17 studies) and availability and physical access (14 studies). Positive perceptions of taste and low cost, relative to other animal-source foods, were drivers of fish purchases in many settings; however, limited physical and economic access were frequently identified as preventing optimal intake. In lakeside communities, fish were increasingly directed toward external markets which reduced the availability and affordability of fish for local households. Few studies considered intra-household variations in fish access according to age, gender or physiological status, which represents an important knowledge gap. There is also scope for future research on seasonal influences on fish access and the design and rigorous evaluation of programmes and policies that address one or more constraints of availability, cost, convenience and preferences

Does village chicken-keeping contribute to young children’s diets and growth? A longitudinal observational study in rural Tanzania

There is substantial current interest in linkages between livestock-keeping and human nutrition in resource-poor settings. These may include benefits of improved diet quality, through animal-source food consumption and nutritious food purchases using livestock-derived income, and hazards of infectious disease or environmental enteric dysfunction associated with exposure to livestock feces. Particular concerns center on free-roaming chickens, given their proximity to children in rural settings, but findings to date have been inconclusive. This longitudinal study of 503 households with a child under 24 months at enrolment was conducted in villages of Manyoni District, Tanzania between May 2014, and May 2016. Questionnaires encompassed demographic characteristics, assets, livestock ownership, chicken housing practices, maternal education, water and sanitation, and dietary diversity. Twice-monthly household visits provided information on chicken numbers, breastfeeding and child diarrhea, and anthropometry was collected six-monthly. Multivariable mixed model analyses evaluated associations between demographic, socioeconomic and livestock-associated variables and (a) maternal and child diets, (b) children’s height-for-age and (c) children’s diarrhea frequency. Alongside modest contributions of chicken-keeping to some improved dietary outcomes, this study importantly (and of substantial practical significance if confirmed) found no indication of a heightened risk of stunting or greater frequency of diarrhea being associated with chicken-keeping or the practice of keeping chickens within human dwellings overnight

Food composition tables in resource-poor settings: Exploring current limitations and opportunities, with a focus on animal-source foods in sub-Saharan Africa

Animal-source foods (ASF) have the potential to enhance the nutritional adequacy of cereal-based diets in low- and middle-income countries, through the provision of high-quality protein and bioavailable micronutrients. The development of guidelines for including ASF in local diets requires an understanding of the nutrient content of available resources. This article reviews food composition tables (FCT) used in sub-Saharan Africa, examining the spectrum of ASF reported and exploring data sources for each reference. Compositional data are shown to be derived from a small number of existing data sets from analyses conducted largely in high-income nations, often many decades previously. There are limitations in using such values, which represent the products of intensively raised animals of commercial breeds, as a reference in resource-poor settings where indigenous breed livestock are commonly reared in low-input production systems, on mineral-deficient soils and not receiving nutritionally balanced feed. The FCT examined also revealed a lack of data on the full spectrum of ASF, including offal and wild foods, which correspond to local food preferences and represent valuable dietary resources in food-deficient settings. Using poultry products as an example, comparisons are made between compositional data from three high-income nations, and potential implications of differences in the published values for micronutrients of public health significance, including Fe, folate and vitamin A, are discussed. It is important that those working on nutritional interventions and on developing dietary recommendations for resource-poor settings understand the limitations of current food composition data and that opportunities to improve existing resources are more actively explored and supported