Carbon footprint of organic beef meat from farm to fork: a case study of short supply chain.

BACKGROUND: Sustainability of food systems is one of the big challenges facing humanity. Local food networks, especially those using organic methods, are proliferating worldwide, and little is known about their carbon footprints. This study aims to assess greenhouse gas (GHG) emissions associated with a local organic beef supply chain using a cradle-to-grave approach. RESULTS: The study determined an overall burden of 24.46 kg CO2  eq. kg-1 of cooked meat. The breeding and fattening phase was the principal source of CO2 in the production chain, accounting for 86% of the total emissions. Enteric methane emission was the greatest source of GHG arising directly from farming activities (47%). The consumption of meat at home was the second high point in GHG production in the chain (9%), with the cooking process being the main source within this stage (72%). Retail and slaughtering activities respectively accounted for 4.1% and 1.1% of GHG emissions for the whole supply chain. CONCLUSION: The identification of the major sources of GHG emissions associated with organic beef produced and consumed in a local food network may stimulate debate on environmental issues among those in the network and direct them toward processes, choices and habits that reduce carbon pollution. © 2018 Society of Chemical Industry.

Effects of fatty acid mixtures on proliferation of peripheral blood mononuclear cells in dairy cows.

This in vitro study was performed to assess the effects of three different mixtures of nonesterifed fatty acids (NEFA) on mitogen-driven proliferation of peripheral blood mononuclear cells (PBMC) in dairy cows. Substantially, the three mixtures differed for n-6 to n-3 fatty acids (FA) ratio and were intended to mimic plasma NEFA composition of cows given fat supplements with different n-6 to n-3 FA ratio. PBMC from six Holstein heifers were cultured in media containing three different mixtures of oleic, palmitic, stearic, linoleic, palmitoleic, or linolenic acid at concentrations mimicking different degree of lipomobilisation. Proliferation of PBMC was stimulated by concanavalin A or pokeweed mitogen (PWM). Low concentrations of the three mixtures (62.5 and 125 µmol/l), did not affect the ability of PBMC to proliferate. Concentrations of the three mixtures mimicking medium-intense lipomobilisation (500, 1,000 and 1,500 µmol/l) impaired to the same extent proliferation of PBMC. The addition to cultures of the three mixtures at concentration of 250 µmol/l, impaired the proliferation only in PBMC stimulated with PWM. Even in this case, the three mixtures did not exert differential effects on PBMC proliferation. Present results reinforce the hypothesis that high concentrations of plasma NEFA play a role in the immunosuppression taking place in cows undergoing intense lipomobilisation, and authorize to suggest that under these conditions different composition of plasma NEFA in terms of different n-6 to n-3 FA ratio cannot prevent their negative effects on lymphocyte proliferation.

Carbon Footprint of Mediterranean Pasture-Based Native Beef: Effects of Agronomic Practices and Pasture Management under Different Climate Change Scenarios.

A better understanding of soil organic carbon (SOC) dynamics is needed when assessing the carbon footprint (CFP) of livestock products and the effectiveness of possible agriculture mitigation strategies. This study aimed (i) to perform a cradle-to-gate CFP of pasture-based beef cattle in a Mediterranean agropastoral system (ii) and to assess the effects on the CFP of alternative tillage, fertilizing, and grazing practices under current (NCC) and future climate change (CC) scenarios. Minimum (Mt) and no-tillage (Nt) practices were compared to current tillage (Ct); a 50% increase (Hf) and decrease (Lf) in fertilization was evaluated against the current (Cf) rate; and rotational grazing (Rg) was evaluated versus the current continuous grazing (Cg) system. The denitrification-decomposition (DNDC) model was run using NCC as well as representative concentration pathways to investigate the effects of farm management practices coupled with future CC scenarios on SOC dynamics, N2O fluxes, and crop yield. Within NCC and CtCf, an emission intensity of 26.9 ± 0.7 kg CO2eq per kg live body weight was estimated. Compared to Ct, the adoption of Mt and Nt reduced the CFP by 20% and 35%, respectively, while NtHf reduced it by 40%. Conservation tillage practices were thus shown to be effective in mitigating greenhouse gas emissions.