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Feed-food competition is the allocation of resources that can be used to feed humans to animal feed instead, a current but unsustainable practise not well documented for aquaculture. Here, we analysed feed-food competition in aquaculture using two measures; natural trophic levels (TLs) and species-specific human-edible protein conversion ratios (HePCRs). The HePCR equals the ratio of human edible protein in feed (input) to the human edible protein in animal produce (output). To provide prospects on aquaculture's potential to convert human inedible by-products into edible biomass, data on aquaculture production were collected and categorized based on natural TLs. HePCRs were computed for four aquaculture species produced in intensive aquaculture systems: Atlantic salmon, common carp, Nile tilapia and whiteleg shrimp. Under current feed use, we estimated that the carp, tilapia and shrimp considered were net contributors of protein by requiring ~0.6 kg of human edible protein to produce 1 kg of protein in the fillet/meat. Considering soya bean meal and fishmeal as food-competing ingredients increased the HePCR to ~2 and turned all of the case-study species into net consumers of protein. To prevent this increase, the use of high-quality food-competing ingredients such as fishmeal, or soya bean products should be minimized in aquaculture feed. In the future, the role of aquaculture in circular food systems will most likely consist of a balanced mix of species at different TLs and from different aquaculture systems, depending on the by-products available.

The objective of this study was to examine social networks in dairy value chains (DVCs) in Kenya and understand how DVC actors' power relationships and trust influence their behaviour regarding milk quality. We conducted a stakeholder analysis using the Net-Map tool in Laikipia, Nakuru and Nyandarua counties in Kenya. VisuaLyzer software was used to analyse the social networks. Thematic content analysis of the discussions, recorded during the mapping exercise, was undertaken using ATLAS.ti. Formal DVC had more actors and dense social networks characterised by vertical and horizontal integration, high levels of power asymmetries between actors, limited trust and short-term contractual arrangements. Informal DVC was characterised by fewer actors and less dense social networks, low levels of power asymmetries between actors and a high level of trust due to the existence of reciprocal personal relationships. Milk was perceived to be of higher quality in the formal value chain reflecting top-down enforcement of milk standards, bottom-up collective action, power asymmetries and contractual relationships. Poor milk quality management in the informal DVC underscores the need for powerful actors, e.g. regulatory agencies, and buyers such as processors, to influence other DVC actors' behavioural change. Understanding and leveraging DVC social networks and actors' power and addressing power asymmetries and enhancing trust between actors will increase compliance with milk quality standards. There is an urgent imperative to design policies and interventions which empower DVC actors, by providing economic incentives, enhancing their skills and knowledge and their access to infrastructure which facilitates milk quality improvement.

If current food consumption patterns continue, the agriculture sector must provide significantly more food in the coming years from the available land area. Some livestock systems engage in feed–food competition as arable land is used for livestock feed rather than as crops for food; reducing the global supply of food. There is a growing argument that to meet future-food demands sustainably, feed–food competition must be minimized. To this end, we evaluated the effectiveness of two refined metrics to quantify feed–food competition in three livestock systems; dairy and its beef, suckler beef and pig production in Ireland. The metrics are edible protein conversion ratio (EPCR) and the land-use ratio (LUR). The EPCR compares the amount of human digestible protein (HDP) in livestock feed against the amount of HDP the livestock produced, calculating how efficiently it produces HDP. However, the LUR compares the potential HDP from a crop system on the land used to produce the livestock's feed against the HDP the livestock system produced. In both metrics, a value

For design of healthy and sustainable diets and food systems, it is important to consider not only the quantity but also the quality of nutrients. This is particularly important for proteins, given the large variability in amino acid composition and digestibility between dietary proteins. This article reviews measurements and metrics in relation to protein quality, but also their application. Protein quality methods based on concentrations and digestibility of individual amino acids are preferred, because they do not only allow ranking of proteins, but also assessment of complementarity of protein sources, although this should be considered only at a meal level and not a diet level. Measurements based on ileal digestibility are preferred over those on faecal digestibility to overcome the risk of overestimation of protein quality. Integration of protein quality on a dietary level should also be done based on measurements on an individual amino acid basis. Effects of processing, which is applied to all foods, should be considered as it can also affect protein quality through effects on digestibility and amino acid modification. Overall, protein quality data are crucial for integration into healthy and sustainable diets, but care is needed in data selection, interpretation and integration.

It is not known whether dietary guidelines proposing a limited intake of animal protein are compatible with the adoption of circular food systems. Using a resource-allocation model, we compared the effects of circularity on the supply of animal-source nutrients in Europe with the nutritional requirements of the EAT-Lancet reference diet. We found the two to be compatible in terms of total animal-source proteins but not specific animal-source foods; in particular, the EAT-Lancet guidelines recommend larger quantities of poultry meat over beef and pork, while a circular food system produces mainly milk, dairy-beef and pork. Compared with the EAT-Lancet reference diet, greenhouse gas emissions were reduced by up to 31% and arable land use reduced by up to 42%. Careful consideration of the feasible substitutability between animal-source foods is needed to define potential roles of animal products in circular human diets.

National food-based dietary guidelines (FBDGs) are generally designed from a human health perspective and often disregard sustainability aspects. Circular food production systems are a promising solution to achieve sustainable healthy diets. In such systems, closing nutrient cycles where possible and minimising external inputs contribute to reducing environmental impacts. This change could be made by limiting livestock feed to available low-opportunity-cost biomass (LOCB). We examined the compatibility of national dietary guidelines for animal products with livestock production on the basis of the feed supplied by available LOCB.We investigated whether the national dietary recommendations for animal products for Bulgaria, Malta, the Netherlands, Sweden, and Switzerland could be met with domestically available LOCB. We used an optimisation model that allocates feed resources to different species of farm animals. Of the resulting scenarios, we assessed the nutritional feasibility, climate impact, and land use.Our results showed the environmental benefits of reducing the recommended animal products in the FBDGs, and that animal products from LOCB could provide between 22% (Netherlands) and 47% (Switzerland) of total protein contributions of the FBDGs. This range covers a substantial part of the nutritional needs of the studied populations. To fully meet these needs, consumption of plant-based food could be increased.Our results contribute to the discussion of what quantities of animal products in dietary guidelines are compatible with circular food systems. Thus, national dietary recommendations for animal products should be revised and recommended quantities lowered. This finding is consistent with recent efforts to include sustainability criteria in dietary guidelines.Swiss National Science Foundation and the Dutch Research Council.

Aims To prove the feasibility and safety of left interventricular septal pacing. Background Right ventricular apical pacing is an established but haemodynamically less favourable pacing method compared with transvenous left ventricular pacing. Alternatively, we propose a simple septal screw-in lead for left interventricular septal pacing. Methods A pacemaker lead with a long insulated screw with the two distal windings forming an active tip was implanted from the right side of the interventricular septum to the subendocardial left side in six goats. A special guiding sheath enabled stable, easy, and swift implantation of the lead. The implantation was performed using fluoroscopy together with, normal and contrast echocardiography (via the long pre-shaped sheath) and electrocardiographic signals (His-bundle recordings in conjunction with atrial and ventricular intracardiac signals). The screw was also positioned at other locations along the free wall, and at the interventricular septum to assess possible adverse effects at other sites. Results An average of 2.21.5 positions per goat was attempted. No adverse effects were noticed during implantation or at necropsy. In two goats, the final position was at the junction of the right ventricular wall and the interventricular septum. Parameters at the final positions were as follows: the pacing threshold was 1.31.0 V at 0.5 ms; the pacing impedance was 1022463 at 4.8 V and 0.5 ms. R-wave amplitudes were 17.67.6 mV. Conclusion Left interventricular septal pacing is feasible. In our study it was safely performed in six goats. The pacing threshold was low, and the stability of the lead system was good. Implantations in humans and animals and haemodynamic evaluations are needed to reveal the potential benefits of this new form of left interventricular septal pacing.

We investigated HFE C282Y and H63D allele frequencies in three Dutch towns in the Netherlands, as well as their association with cardiovascular disease (CVD) mortality. Study subjects were selected from participants of the Monitoring Project on Cardiovascular Disease Risk Factors in the Netherlands carried out in Amsterdam, Doetinchem and Maastricht among35000 subjects, 20-59 years of age. Mortality follow-up lasted 9 to 13 years. A random sample of the cohort (n = 1075) provided information on the total study population. The random sample and all CVD deaths (n = 301) were genotyped for the C282Y and H63D mutation. Adjusted hazard ratios (HR) for CVD mortality were calculated per genotype. C282Y allele frequencies differed significantly between the towns investigated (p = 0.017), whereas the allele frequencies of H63D were similar (p = 0.141) across towns. In Maastricht we found a C282Y allele frequency of 0.086 compared to 0.055 in Amsterdam and 0.054 in Doetinchem. C282Y and H63D heterozygosity did not predict fatal CVD in either men or women, whereas homozygosity for the H63D mutation increased fatal CVD in women (adjusted HR = 8.5; 95% CI = 2.3-31.1). The unexpected high C282Y allele frequency in Maastricht is in line with the recent evidence of a Celtic origin of citizens from the former southern Netherlands and with prehistorical population migrations revealed in the context of the international Genographic Project, a landmark study of prehistorical human migrations around the globe. We recommend that when designing national screening programmes and national registries for genetic disorders, potential regional prevalence differences should be taken into account.

Aims/hypothesis: The aim of this study was to examine the association of consumption of coffee and tea, separately and in total, with risk of type 2 diabetes and which factors mediate these relations. Methods: This research was conducted as part of the Dutch Contribution to the European Prospective Investigation into Cancer and Nutrition, which involves a prospective cohort of 40,011 participants with a mean follow-up of 10 years. A validated food-frequency questionnaire was used to assess coffee and tea consumption and other lifestyle and dietary factors. The main outcome was verified incidence of type 2 diabetes. Blood pressure, caffeine, magnesium and potassium were examined as possible mediating factors. Results: During follow-up, 918 incident cases of type 2 diabetes were documented. After adjustment for potential confounders, coffee and tea consumption were both inversely associated with type 2 diabetes, with hazard ratios of 0.77 (95% CI 0.63-0.95) for 4.1-6.0 cups of coffee per day (p for trend=0.033) and 0.63 (95% CI: 0.47-0.86) for >5.0 cups of tea per day (p for trend=0.002). Total daily consumption of at least three cups of coffee and/or tea reduced the risk of type 2 diabetes by approximately 42%. Adjusting for blood pressure, magnesium, potassium and caffeine did not attenuate the associations. Conclusions/interpretation: Drinking coffee or tea is associated with a lowered risk of type 2 diabetes, which cannot be explained by magnesium, potassium, caffeine or blood pressure effects. Total consumption of at least three cups of coffee or tea per day may lower the risk of type 2 diabetes.

A method is presented for in-situ hybridization to mRNA in second-stage juveniles (J2) of the soybean cyst nematode Heterodera glycines. The protocol was developed using a digoxigenin-labeled RNA probe transcribed from cDNA of a cellulase gene that was known to be expressed in the subventral esophageal glands of H. glycines. Formaldehyde-fixed J2 were cut into sections with a vibrating razor blade to make the inside of the nematodes accessible for probing. These nematode fragments then were hybridized in suspension with riboprobe, and labeled with an alkaline phosphatase-conjugated antibody to digoxigenin. Staining with nitroblue tetrazolium and bromo-chloro-indolyl phosphate revealed a highly specific hybridization signal to mRNA within the cytoplasm of the subventral gland cells, using this specific antisense probe. This in-situ hybridization protocol will be useful for the characterization and identification of esophageal gland secretion genes in plant-parasitic nematodes, among other applications.

Two beta-1,4-endoglucanase (EGase) cDNAs were isolated from Globodera tabacum, the tobacco cyst nematode, and have been designated as GT-eng-1 and GT-eng-2. GT-eng-1 and GT-eng-2 encode precursor proteins with a predicted secretion signal sequence, cellulolytic catalytic domain, and a linker domain. The protein product GT-ENG-1 contains an additional 95 amino acid carboxy terminal sequence with strong similarity to type II cellulose binding domains. Riboprobes and polyclonal antibodies raised to recombinant cyst nematode EGases were used to follow expression patterns of EGase transcripts and proteins throughout the nematode life cycle. EGase transcripts and proteins were specifically detected within the subventral esophageal gland cells of G. tabacum second-stage juveniles (J2) within eggs prior to hatching, in preparasitic J2, and in parasitic J2 that had invaded tobacco roots. EGase transcripts and proteins were not detected in G. tabacum after the molt to the sedentary J3, J4, and adult female life stages. Interestingly, EGase transcription and translation resumed in the subventral esophageal glands of late J4 males. It is hypothesized that secreted EGases play a major role to facilitate intracellular migration of G. tabacum within tobacco roots.

We prove that one of the simplest periodic hexagonal division sequences cannot be produced by any finite parallel generating system of a certain type (map D0L system).

Computer simulation of cell division patterns in the apical region of fern gametophytes illustrates the development of a concave apical front and the subsequent heart shape when the division ratio is below a certain threshold. Here, I apply the concept of division ratio to the gametophytes of three fern species and show that the same relationship between cell division pattern and global shape exists. This indicates that the method of quantitative analysis of cell division patterns is a promising addition to existing methods for two-dimensional growth analysis.

We have investigated the relationship between cell division and shape in mathematical models of fern gametophyte development. In particular, we attempted to infer what properties of cell division patterns are responsible for the development of heart-shaped thalli. We focused on those types of gametophytes that develop from an initial cell, splitting off segments alternately to the left and to the right. Computer simulations showed that a heart shape developed when the ratio between the rates of anticlinal and periclinal divisions in segments (the division ratio) was below a certain threshold. In the computer simulations we used map L-systems for the generation of cell division patterns and a center-of-gravity algorithm for the computation of cell shapes. The division ratio provided a quantitative characterization of the tendency of the cell division pattern to develop a heart shape. Together with map DOL-systems it can be applied to real gametophytes to investigate their morphogenesis.

Urinary urea concentration is an important predictor of NH3 emission from dairy barns. To reduce urinary urea concentration, accurate and precise prediction of urea concentration for different feeding regimes is a prerequisite. The objective of this research, therefore, was to predict urinary urea concentration of a cow using feed characteristics. To compute urinary urea concentration of a cow, we predicted: urine volume; urinary N excretion, using a regression or a mechanistic model; and the relationship between urinary urea concentration and urinary N concentration, which was derived from experimental data. Model results were validated using experimental data. Cows were fed one of nine diets, which was a combination of one of three rumen-degradable protein balances, and one of three roughage compositions. Each diet was repeated once. Measured parameters included herd, diet, and urine characteristics. Observed urinary urea concentration can be predicted with reasonable accuracy from existing models to predict urine volume and urinary N excretion using feed characteristics. The regression model predicted N excretion slightly better than the mechanistic model. In addition, input parameters required for the regression model are recorded at each dairy farm in The Netherlands. This regression model, therefore, can be used by animal nutritionists and producers to determine diets that result in a reduced NH3 emission.

Expression of single-chain antibody fragments (scFvs) in the plant cytosol is often cumbersome. It was unexpectedly shown that addition at the C-terminus of the ER retention signal KDEL resulted in significantly improved expression levels. In this report the cytosolic location of the scFv-CK was confirmed, excluding possible mistranslocation to other subcellular compartments. It was shown that expression of several other scFvs was also improved in tobacco protoplasts. In addition expression was improved in transgenic potato. Changing from KDEL to KDEI did not affect the enhanced protein expression level. Addition of the KDEL motif is a simple and straightforward tool to stabilize in planta cytosolic expression of many scFvs.