Environmental impacts of innovative dairy farming systems aiming at improved internal nutrient cycling: A multi-scale assessment

Several dairy farms in the Netherlands aim at reducing environmental impacts by improving the internal nutrient cycle (INC) on their farm by optimizing the use of available on-farm resources. This study evaluates the environmental performance of selected INC farms in the Northern Friesian Woodlands in comparison to regular benchmark farms using a Life Cycle Assessment. Regular farms were selected on the basis of comparability in terms of milk production per farm and per hectare, soil type and drainage conditions. In addition, the environmental impacts of INC farming at landscape level were evaluated with the integrated modelling system INITIATOR, using spatially explicit input data on animal numbers, land use, agricultural management, meteorology and soil, assuming that all farms practised the principle of INC farming. Impact categories used at both farm and landscape levels were global warming potential, acidification potential and eutrophication potential. Additional farm level indicators were land occupation and non-renewable energy use, and furthermore all farm level indicators were also expressed per kg fat and protein corrected milk. Results showed that both on-farm and off-farm non-renewable energy use was significantly lower at INC farms as compared with regular farms. Although nearly all other environmental impacts were numerically lower, both on-farm and off-farm, differences were not statistically significant. Nitrogen losses to air and water decreased by on average 5 to 10% when INC farming would be implemented for the whole region. The impact of INC farming on the global warming potential and eutrophication potential was, however, almost negligible (<2%) at regional level. This was due to a negligible impact on the methane emissions and on the surplus and thereby on the soil accumulation and losses of phosphorus to water at INC farms, illustrating the focus of these farms on closing the nitrogen cycle. (C) 2015 Elsevier B.V. All rights reserved

Potential of Extensification of European and Dutch Agriculture for a More Sustainable Food System Focusing on Nitrogen and Livestock

Most global strategies for future food security focus on sustainable intensification of production of food and involve an increase of nitrogen (N) fertilizer use, livestock production and risk of N pollution. In this chapter, we explore the potential of sustainable extensification for agriculture in the European Union (EU) and the Netherlands by analyzing cases and scenario studies focusing on reducing N inputs and livestock densities. Benefits of extensification to society include higher local biodiversity and less environmental pollution. Societal costs of N losses in the EU from agriculture are substantial and for 2008 are here estimated at 0.3-1.9% of the gross domestic product (GDP). Extensification also has risks such as a reduction of yields and therewith a decrease of both GDP and farm income. This also implies a smaller contribution to global food production and, potentially, an increase of global demand for land. For N-intensive agricultural systems in northwest EU, a reduction of N fertilization rate and livestock densities of up to 30% would reduce the external cost of N pollution to such an extent that society as a whole would benefit. However, compensation would be needed for net loss of farm income, e.g., by price premiums for cleaner production or improved animal welfare. Extensification scenarios with > 30% decrease of livestock production would require adjustment of human diets. A 2030 scenario for the EU halving consumption and production of animal products (demitarian diet) is here estimated to reduce N pollution by 10%, benefits human health and would transform the EU from a feed importer to a food exporter

Retinopathy in type 2 diabetes mellitus is associated with increased intima-media thickness and endothelial dysfunction

Background  Microangioathy and macroangiopathy in type 2 diabetes mellitus (T2DM) frequently coexist. Both types of vascular complications share traditional risk factors. It is not clear whether the presence of microangiopathy, such as diabetic retinopathy (DR), constitutes a predictor of atherosclerosis in T2DM. Here we described the search for the association between DR and intima-media thickness (IMT) in T2DM. We also compared endothelial function in subjects with and without DR. Material and methods  We examined 182 consecutive patients with T2DM for at least 5 years (mean age at examination 56·3 ± 6·52 years). We assessed (i) IMT of carotid artery by ultrasound and (ii) endothelial function by flow-mediated dilatation (FMD) method as well as by measurement of concentrations of von Willebrand factor (vWF) and s-ICAM-1. All patients underwent ophthalmological examination. Statistical analysis included Student's, Mann–Whitney, chi-square, Fisher tests and multiple regression. Results  DR was found in 71 (39·0%) subjects. IMT was higher in patients with DR than those without DR (0·87 mm vs. 0·79 mm, respectively, P = 0·0001). FMD was lower in the complication group than in subjects without DR (8·38% vs. 10·45%, respectively, P = 0·0023). Concentrations of s-ICAM-1 and vWF were not different between the groups. In multiple regression analysis, DR was among the predictors of increased IMT (P = 0·016) and decreased FMD (P = 0·002). We did not find a significant association of DR with vWF and s-ICAM-1 (P = 0·09 and P = 0·11, respectively). Conclusions  DR is associated with increased IMT and endothelial dysfunction in T2DM. Impaired endothelial function may be a common denominator of pathogenesis of microvascular complications and atherosclerosis in T2DM