Food Transfer Research Articles

LC-MS analyses of microcystins in fish tissues overestimate toxin levels—critical comparison with LC-MS/MS

Microcystins are cyclic peptide toxins with hepatotoxic and tumour-promoting properties which are produced in high quantities in freshwater cyanobacterial water blooms, and several studies have reported microcystin accumulation in fish with possible food transfer to humans. In this study, we provide the first comparison of liquid chromatography with single mass-spectrometric and with tandem mass-spectrometric detection for analyses of microcystins in complex fish tissue samples. Use of traditional single mass spectrometry (i.e. monitoring of ions with m/z 519.5 for microcystin-RR and m/z 995.5 for microcystin-LR) was found to provide false-positive responses, thus overestimating the concentrations of microcystins in the tissue samples. More selective tandem mass spectrometry seems to provide more reliable results. The concentrations of microcystins detected by tandem mass spectrometry in fish from controlled-exposure experiments were more than 50% lower in comparison with concentrations obtained by single mass spectrometry. Extensive analyses of edible fish parts-muscles (148 fish specimens from eight different species from five natural reservoirs with dense cyanobacterial water blooms)-showed negligible microcystin concentrations (all analyses below the limit of detection; limit of detection of 1.2-5.4 ng/g fresh weight for microcystin-RR, microcystin-YR and microcystin-LR in multiple reaction monitoring mode). Our findings have practical consequences for critical re-evaluation of the health risks of microcystins accumulated in fish.

Rice market integration and food security in Nepal: The role of cross-border trade with India

Coarse rice market integration between Nepal and India is analyzed applying a threshold autoregressive model. The price response behaviour of traders is found to be consistent with an asymmetric price adjustment mechanism, indicating coarse rice prices in Nepal respond to shocks originating in India. The results show that adjustments to negative price deviations from long-run stable equilibrium are faster than adjustments to the positive ones given a null threshold. Given that trade flows mainly from India to Nepal, Nepali traders would adjust their prices upward to align with the long-run equilibrium value relatively more quickly in the case of negative price deviations, than if the price deviations were positive. Such a high speed of adjustment to negative price deviations could be detrimental to net food buyers’ food security status in the absence of a price stabilization mechanism. However, a price stabilization policy in Nepal, a food deficit and import dependent country, would hardly have any effect on prices unless further effort is made to build up the level of national food reserves for short-term food security interventions. In the current context of structurally low levels of national food reserves, an alternative short-term policy such as foreign aid, in the form of food or income transfers, targeting the most vulnerable households to price increases is necessary through social safety net programmes. In the long-run, an improvement of transportation infrastructure between market hubs (other than the Biratnagar trade basin) in the Terai (Nepal) and India would contribute to the reduction of transaction costs and create incentives for more competition in formal cross-border trade with India. In times of negative shocks such as the high food price crisis in 2008, restrictive food trade policies in India will continue to undermine household food security in Nepal.

Cash transfers and high food prices: Explaining outcomes on Ethiopia’s Productive Safety Net Programme

An ongoing and highly politicised debate concerns the relative efficacy of cash transfers versus food aid. This paper aims to shed light on this debate, drawing on new empirical evidence from Ethiopia’s Productive Safety Net Programme (PSNP). Our data derive from a two-wave panel survey conducted in 2006 and 2008. Ethiopia has experienced unprecedented rates of inflation since 2007, which have reduced the real purchasing power of PSNP cash payments. Our regression findings confirm that food transfers or ‘cash plus food’ packages are superior to cash transfers alone – they enable higher levels of income growth, livestock accumulation and self-reported food security. These results raise questions of fundamental importance to global humanitarian response and social protection policy. We draw out some implications for the design of social transfer programmes and describe some steps that could be taken to enable ‘predictable transfers to meet predictable needs’.

The influence of social hunger on food distribution and its implications for disease transmission in a honeybee colony

Social insect colonies are characterized by extensive interactions among individuals, exchanges that can also potentially transmit pathogens. The large majority of these social interactions in a honeybee colony result from food transfer among individuals. Since colony hunger is likely to have a significant influence on these interactions, we investigated its effect on the distribution of food within the colony. By pulsing two colonies having different amounts of stored food with a radioactive label, we found that a starved colony sent out a larger number of foragers, brought in more food, and stored more of it than the satiated colony. We also found that the food brought into a starved colony was distributed more uniformly within each age class than that in the satiated colony. The queen and the young individuals received the lowest exposure to the label even though the label entered different regions of the colony at the same rate. The satiation level of the colony did not influence the relative exposures of different age groups to the label but a higher amount of it was stored in the hungry colony. We discuss the significance of these results in terms of the role played by the organizational structure of the honeybee colony on the transmission dynamics of an infectious disease.

Perspectives on food transfer between parent and offspring : Comments on Ueno’s article

Perspectives on food transfer between parent and offspring : Comments on Ueno’s article

Pathways of food: mobility and food transfers in Southern African cities

Using recent multi-city survey data, the analysis demonstrates that informal rural–urban and urban–urban food transfers make important contributions to the food budgets of chronically food-insecure, poor households in the rapidly urbanising cities of Southern Africa. The paper outlines why dealing with food and nutrition security is a priority and multi-faceted urban development challenge, and argues for development policy and planning that seeks to enhance these widely prevalent household linkages by supporting urban (and rural) livelihoods. Given the links between food and nutrition security on the one hand, and human development and wealth generation on the other, using a food lens is one useful way of devising approaches to urban development that are people-centred and pro-poor, which is important in the Southern African context of widespread rural–urban migration and pervasive urban poverty.

Caching Eurasian skylarks Alauda arvensis by the Montagu's harrier Circus pygargus

Caching Eurasian skylarksAlauda arvensisby the Montagu's harrierCircus pygargusWe observed caching Eurasian skylarks by a radio-tracked male Montagu's harrier in eastern Poland. This strategy, in combination with the courtship feeding of the female, was an important element of courtship. Frequent food transfers to the female could reflect a good condition of the male and its good hunting abilities.

From the Editors

From the Editors

Annual profile of fecal androgen and glucocorticoid levels in free-living male American kestrels from southern mid-latitude areas

Fecal samples and behavioral data were collected at a fortnightly basis during 11 months period from free-living male American kestrels living in southeast Brazil (22°S latitude). The aim was to investigate the seasonal changes in testicular and adrenal steroidogenic activity and their correlation to reproductive behaviors and environmental factors. The results revealed that monthly mean of fecal glucocorticoid metabolites in May and June were higher than those estimated in November. In parallel, monthly mean of androgen metabolites in September was higher than those from January to April and from October to November. Molt took place from January to March, whereas copulation was observed from June to October but peaked in September. Nest activity and food transfer to females occurred predominantly in October, and parental behavior was noticed only in November. Territorial aggressions were rare and scattered throughout the year. Multiple regression analysis revealed that fecal androgen levels are predicted by photoperiod and copulation, while fecal glucocorticoid levels are only predicted by photoperiod. Bivariate correlations showed that fecal androgen metabolites were positively correlated with fecal glucocorticoid metabolites and copulation, but negatively correlated with molt. Additionally, copulation was positively correlated with food transfer to females and nest activity, but negatively correlated with molt. These findings suggest that male American kestrels living in southeast Brazil exhibit significant seasonal changes in fecal androgen and glucocorticoid concentrations, which seem to be stimulated by decreasing daylength but not by rainfall or temperature.

Generational Economics in a Changing World

Human hunter-gatherers evolved a life strategy that involved extensive sharing of food and support within and across generations, social behaviors that coevolved with the cognitive and emotional mental apparatus needed to sustain such sophisticated sociality. Adults at all ages produced surplus food which was transferred downwards to children, to support their prolonged period of nutritional dependency, until around age 20. Over a long period of economic development, and a shorter period of demographic transition, generational relations interacted with the changing environment, including changing population age distributions, life cycle behavior, technologies, and institutional arrangements. Similar patterns may have held during land abundant subsistence agriculture, but in intensive agriculture, perhaps due to their property rights in land, the elderly became net consumers in a stage of partial retirement, when they were sustained in part by food transfers from their adult children. At the same time, assets in general became more important – land, buildings, property of all sorts. These assets provided an alternative means for the elderly to support themselves in retirement. These trends continued as agriculture gave way to industry, with retirement earlier and more complete. The growth of a public sector reinforced the pattern of downward transfers with public education and health care for children. However, as states industrialized and the welfare state grew, transfers to the elderly for pensions and health care became increasingly important, with a fiscal effect exacerbated by population aging. At the same time, the growth of capital and financial institutions provided new forms of asset accumulation along with private pensions. These two trends reduced the role of the family in providing for the elderly. Our evolved sociality and ethic of sharing and fairness is now expressed through welfare state redistributive programs, and continuing and intensifying public and private investment in children. But now population aging, interacting with the public programs for the elderly, has led to a reversal in the direction of resource flows across age, from downward (old to young) to upward (young to old). We are currently able both to invest in the young and care for the newly dependent elderly. However, the old age dependency ratio is projected to double or triple in coming decades in the rich industrial countries. The public costs of the elderly may increasingly compete with investments in children through the public sector budget constraint. It remains to be seen whether the elderly, in the context of new public policies, will opt to work until substantially older ages, and whether the rapid growth of health care expenditures will be restrained.

The effect of eating utensil weight on functional arm movement in people with Parkinson’s disease: a controlled clinical trial

Objective: To investigate the effect of eating utensil weight on kinematic performance in people with Parkinson’s disease. Design: A counterbalanced repeated-measures design. Setting: A motor control laboratory in a university setting. Subjects: Eighteen adults with Parkinson’s disease and 18 age-matched controls. Experimental conditions: Each participant performed a food transfer task using spoons of three different weights: lightweight (35 g), control (85 g) and weighted (135 g). Kinematic variables of arm movement were derived and compared between conditions. Main measures: Kinematic variables of arm movement, including movement time, peak velocity and number of movement units. Results: Utensil weights significantly affected the movement kinematics of all participants. Both groups had fewer movement units in the lightweight condition (Parkinson’s disease group: 22.18, controls: 19.89) than in the weighted condition (Parkinson’s disease group: 22.68, controls: 21.36), suggesting smoother movement in the former condition. In addition, both groups had higher peak velocity in the lightweight than in the weighted condition. Conclusions: Our findings suggest that a lightweight utensil may facilitate smoother and higher-velocity arm movement than a weighted one in people with Parkinson’s disease.

The Welfare Effects of Integrating HIV/AIDS Treatment with Cash or in Kind Transfers

The fight against HIV/AIDS involves the implementation of various social protection programs to improve the welfare of patients and affected households. Free or subsidized AIDS treatment is now being provided to at various scales in the afflicted regions of the world. In recent years, initiatives integrating AIDS treatment with social transfers have emerged thus raising questions on the welfare effects of this integration and if these effects are different or larger than AIDS treatment alone. The objective of this review is to establish the following: a) to assess the welfare impact of integrating AIDS treatment with cash or in kind transfers and compare them to the welfare effects of AIDS treatment alone and b) to determine the effects of the cash transfer and AIDS treatment combination versus the in kind transfer and AIDS treatment combination. The authors review economic theory and empirical studies and find that AIDS treatment alone improves patients� health and survival rates while increasing labour force participation rates. Integrating AIDS treatment with cash or in kind transfers theoretically has ambiguous effect on labour supply, while empirical evidence shows improvements in patients� health, food consumption, labour activity and adherence to treatment when food transfers are integrated with AIDS treatment. Some evidence shows that cash transfers increased household income and food consumption when integrated with AIDS treatment. However since current empirical studies are few , the authors come to a conclusion that there are opportunities for further research especially direct comparing AIDS treatment alone and its integration with cash or in kind transfers.

The changing global carbon cycle: linking plant–soil carbon dynamics to global consequences

Summary 1. Most current climate–carbon cycle models that include the terrestrial carbon (C) cycle are based on a model developed 40 years ago by Woodwell & Whittaker (1968) and omit advances in biogeochemical understanding since that time. Their model treats net C emissions from ecosystems as the balance between net primary production (NPP) and heterotrophic respiration (HR, i.e. primarily decomposition). 2. Under conditions near steady state, geographic patterns of decomposition closely match those of NPP, and net C emissions are adequately described as a simple balance of NPP and HR (the Woodwell‐Whittaker model). This close coupling between NPP and HR occurs largely because of tight coupling between C and N (nitrogen) cycles and because NPP constrains the food available to heterotrophs. 3. Processes in addition to NPP and HR become important to understanding net C emissions from ecosystems under conditions of rapid changes in climate, hydrology, atmospheric CO2, land cover, species composition and/or N deposition. Inclusion of these processes in climate–C cycle models would improve their capacity to simulate recent and future climatic change. 4. Processes that appear critical to soil C dynamics but warrant further research before incorporation into ecosystem models include below‐ground C flux and its partitioning among roots, mycorrhizas and exudates; microbial community effects on C sequestration; and the effects of temperature and labile C on decomposition. The controls over and consequences of these processes are still unclear at the ecosystem scale. 5. Carbon fluxes in addition to NPP and HR exert strong influences over the climate system under conditions of rapid change. These fluxes include methane release, wildfire, and lateral transfers of food and fibre among ecosystems. 6. Water and energy exchanges are important complements to C cycle feedbacks to the climate system, particularly under non‐steady‐state conditions. An integrated understanding of multiple ecosystem–climate feedbacks provides a strong foundation for policies to mitigate climate change. 7. Synthesis. Current climate systems models that include only NPP and HR are inadequate under conditions of rapid change. Many of the recent advances in biogeochemical understanding are sufficiently mature to substantially improve representation of ecosystem C dynamics in these models.

HIV/AIDS, declining family resources and the community safety net

Families play central roles in the HIV/AIDS pandemic, caring for both orphaned children and the ill. This extra caregiving depletes two family resources essential for supporting children: time and money. We use recent data from published studies in sub-Saharan Africa to illustrate deficits and document community responses. In Botswana, parents caring for the chronically ill had less time for their preschool children (74 versus 96 hours per month) and were almost twice as likely to leave children home alone (53% versus 27%); these children experienced greater health and academic problems. Caregiving often prevented adults from working full time or earning their previous level of income; 47% of orphan caregivers and 64% of HIV/AIDS caregivers reported financial difficulties due to caregiving. Communities can play an important role in helping families provide adequate childcare and financial support. Unfortunately, while communities commonly offer informal assistance, the value of such support is not adequate to match the magnitude of need: 75% of children's families in Malawi received assistance from their social network, but averaging only US$81 annually. We suggest communities can strengthen the capacity of families by implementing affordable quality childcare for 0–6 year olds, after-school programming for older children and youth, supportive care for ill children and parents, microlending to enhance earnings, training to increase access to quality jobs, decent working conditions, social insurance for the informal sector, and income and food transfers when families are unable to make ends meet.

Development of an Improved Local-Ingredient-Based Complementary Food and Technology Transfer to Rural Housewives

Food technology transfer to rural households, based on local ingredients, is a relevant and sustainable strategy to ensure better nutrition of young children. Objective. To develop an improved mush based on local ingredients and evaluate the potential for transferring its technology to rural housewives. We developed a flour-based food using Alicom software and performed laboratory trials to evaluate its actual nutritional quality. Then we recruited housewives from each of the 27 project villages and trained them in flour production and mush preparation twice daily, 6 days a week, for 26 weeks. Mush was sampled during the training session and at weeks 4, 12, and 22 and evaluated for actual flow distance and dry matter content, which served to estimate energy density and iron and zinc contents. The laboratory trials reported average energy densities of 103 kcal/l00 g, iron contents of 2.6 mg/100 kcal, and zinc contents of 1.2 mg/100 kcal. The average (+/- SD) energy densities of the mush samples obtained during the training session and at weeks 4, 12, and 22 were 103.0 +/- 5.6, 103.3 +/- 5.2, 107.9 +/- 11.5, and 101.3 +/- 8.7 kcal/100 g, respectively. The average iron contents were 2.3 +/- 0.5, 2.3 +/- 0.5, 2.6 +/- 0.3, and 1.8 +/- 0.8 mg/ 100 kcal, respectively, and the average zinc contents were 1.6 +/- 0.1, 1.6 +/- 0.1, 1.7 +/- 0.1, and 1.6 +/- 0.2 mg/100 kcal. Developing a suitable complementary food from local ingredients and educating households in nutrition and use of local products are feasible. Such education should come with measures aimed at improving the accessibility of some ingredients to ensure feasibility and sustainability.

Early reproductive maturity among Pumé foragers: Implications of a pooled energy model to fast life histories

Life history theory places central importance on relationships between ontogeny, reproduction, and mortality. Fast human life histories have been theoretically and empirically associated with high mortality regimes. This relationship, however, poses an unanswered question about energy allocation. In epidemiologically stressful environments, a greater proportion of energy is allocated to immune function. If growth and maintenance are competing energetic expenditures, less energy should be available for growth, and the mechanism to sustain rapid maturation remains unclear. The human pattern of extended juvenile provisioning and resource sharing may provide an important source of variation in energy availability not predicted by tradeoff models that assume independence at weaning. We consider a group of South American foragers to evaluate the effects that pooled energy budgets may have on early reproduction. Despite growing up in an environment with distinct seasonal under-nutrition, harsh epidemiological conditions, and no health care, Pumé girls mature quickly and initiate childbearing in their midteens. Pooled energy budgets compensate for the low productivity of girls not only through direct food transfers but importantly by reducing energy they would otherwise expend in foraging activities to meet metabolic requirements. We suggest that pooled energy budgets affect energy availability at both extrinsic and intrinsic levels. Because energy budgets are pooled, Pumé girls and young women are buffered from environmental downturns and can maximize energy allocated to growth completion and initiate reproduction earlier than a traditional bound-energy model would predict.

Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France)

During a decade (1996–2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp′-DDE, dieldrin, aldrin, heptachlor, endosulfan…) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas.

NEATS: A Network Economics Approach to Trophic Systems

The main principle of the economic approach to a trophic system we propose here lies in assuming that there is a transfer of food along a path between a prey and a predator if, for the predator, the benefits are greater than costs of predation on this path. Conversely, if the costs exceed the benefits, there are no flows. This trade-off, considered all along the food chains of an ecosystem, together with ecological processes (assimilation, somatic maintenance) results in a model coupling mass balance equations (biological constraints) and complementarity principles (Walras’ law). Here is the core of the Network Economics Approach to Trophic Systems (NEATS). We illustrate with simple examples of ecosystems how these principles result in algebraic equations which can be analyzed mathematically and solved numerically. We show, in a more sophisticated example of an input/output trophic network, that they result in “affine variational inequalities”, whose solutions can be estimated. We make explicit how the approach can be applied to address ecological questions, concerning differences of productivity, causes of biological diversity, or the nature of controls in marine ecosystems.

Intersexual food transfer among orangutans: do females test males for coercive tendency?

Tolerated transfer of food among adults is rare among primates, except in humans. Here, we present data on a consistent pattern of tolerated intersexual transfer of food (held in hand, foot, or mouth by the owner) among adult orangutans, in two different natural populations (Pongo abelii and Pongo pygmaeus wurmbii), based on ca. 9,000 h of focal observation per site. Although rare, intersexual food transfers were disproportionately from males to sexually active females and involved food that was equally available to both sexes. There was no evidence for direct trading of food for social favors (mating, grooming, or agonistic support) or for sharing under pressure of harassment. However, females frequently protested with loud screams when males, especially unflanged ones, attempted to take food they possessed, and also when males responded aggressively to their taking attempt. Since associations ended sooner when the female emitted noisy calls, a male who did not allow a female to take food from him risked losing the association. These findings support the hypothesis that by taking food, a sexually active female may test the male's tendency toward violence. Thus, intersexual food taking in orangutans is based on female leverage, resulting in a species-wide female entitlement to male “generosity”. The inhibition of food defense required for this kind of transaction may also form the basis for sharing patterns among species in which nutritional benefits have become important, such as chimpanzees and perhaps human foragers.

Modelling the number of viable vegetative cells ofBacillus cereuspassing through the stomach

Model the number of viable vegetative cells of B. cereus surviving the gastric passage after experiments in simulated gastric conditions. The inactivation of stationary and exponential phase vegetative cells of twelve different strains of Bacillus cereus, both mesophilic and psychrotrophic strains isolated from food and faeces from healthy and ill individuals, in simulated gastric conditions was determined using decimal reduction times at low pH (D(pH)). Subsequently inactivation rates were calculated. Inclusion of the inactivation rates into models describing the course of the gastric pH after the consumption of meal of solid food and the transfer of food from the stomach to the small intestine resulted in numbers of viable Bacillus cereus vegetative cells able to pass the stomach. According to the model, 3-26% of the ingested vegetative cells from Bacillus cereus may survive the gastric passage, dependent on the growth phase of the vegetative cells, the type of strains, and the age of the consumer. Vegetative cells of Bacillus cereus may be involved in the onset of diarrhoeal disease to a greater extent than expected since up to 26% of the ingested cells survive simulated gastric conditions.