ECOALIM: A Dataset of Environmental Impacts of Feed Ingredients Used in French Animal Production

How much does overnutrition weigh? The environmental and social impacts of Metabolic Food Waste in Italy

Excess Food Energy Intake (EFEI), namely Metabolic Food Waste (MFW) corresponds to excess calorie intake related to overconsumption of food and is responsible for overweight (OW) and obesity (OB) conditions. Identifying its causes and impacts could be important, so that it can be prevented and reduced, generating health, environmental and societal benefits. Therefore, this research quantifies MFW among OW and OB adult populations (18-75 years) in Italy and its environmental and social implications. Life cycle assessment (LCA) through the Simapro 9.5 software was used and then, the results were monetized according to the Environmental Price Handbook to understand the real environmental cost. Finally, Social LCA (S-LCA) was considered following the Product Social Impact Assessment (PSILCA) guidelines to understand the potential social risks behind the food that ends up on our plates. The results highlight the amount of MFW in Italy is 2696 billion kcal/year corresponding to 1.59 Mtons over-consumed food/year, while the impacts are mainly related to global warming (8.78 Mtons CO2 eq/year, or 2.29 % of the total Italian CO2 emissions), terrestrial ecotoxicity (843,451 tons 1.4-DCB/year), freshwater ecotoxicity (222,483 tons 1.4 DCB eq/year), and land consumption (8 million m2a eq/year), mostly due to the meat, fats and oils and sweets overconsumption. Impacts monetization also shows that MFW could induce an environmental price of € 1340/per capita/year, and finally, the S-LCA reveals how overconsumption of food has the potential to affect gender discrimination, water depletion, trade union, and social discrimination due to the high proportion of labor migrants in the agricultural sector.

Eco-friendly diet: nutrient digestibility, nitrogen and energy balances and growth performance of growing pigs

The traditional approach to formulating pig diets is based only on minimizing cost while meeting nutritional requirements and thus does not consider the environmental impacts associated with producing feed ingredients. To reduce the overall environmental impact of pork production, feed ingredients can be considered to formulate environmentally friendly diets. However, their potential effects on pig performance could decrease environmental benefits at the farm gate. The objective of this study was to quantify the effects of such eco-friendly pig diets on nitrogen (N) and energy (E) balances, the components of heat production (HP), and the performance of growing pigs. Digestibility coefficients of dry matter (84.5% vs. 88.2%, P < 0.01) and N (80.4% vs. 86.3%, P < 0.01) were significantly lower for the eco-friendly diet than the Control-diet (a commercial diet used in France). N excretion in feces was significantly higher for the group of pigs fed the eco-friendly diet than for the group fed the Control-diet (9.8 vs. 6.9 g/d, respectively, P = 0.01), while the N retention tended to be lower (27.8 vs. 30.3 g/d, respectively; P = 0.06). The metabolizable E:digestible E ratio did not differ between diets, but total HP was significantly lower for the eco-friendly diet group than for the Control-diet group (1,340 vs. 1,388 kJ/kg body weight0.60/d, respectively, P = 0.03). Using feed ingredients with lower environmental impacts, such as locally produced protein or co-products from wheat processing, is an effective way to decrease the environmental impacts of pig production. However, the nutritional composition of these eco-friendly ingredients could be overestimated, in particular the true digestibility of amino acids. This indicates the need to better estimate and consider the true digestibility of eco-friendly diets to decrease environmental impacts of livestock production without decreasing animal performance.

From straw to salmon: a technical design and energy balance for production of yeast oil for fish feed from wheat straw

BACKGROUND

Aquaculture is a major user of plant-derived feed ingredients, such as vegetable oil. Production of vegetable oil and protein is generally more energy-intensive than production of the marine ingredients they replace, so increasing inclusion of vegetable ingredients increases the energy demand of the feed. Microbial oils, such as yeast oil made by fermentation of lignocellulosic hydrolysate, have been proposed as a complement to plant oils, but energy assessments of microbial oil production are needed. This study presents a mass and energy balance for a biorefinery producing yeast oil through conversion of wheat straw hydrolysate, with co-production of biomethane and power.

RESULTS

The results showed that 1 tonne of yeast oil (37 GJ) would require 9.2 tonnes of straw, 14.7 GJ in fossil primary energy demand, 14.6 GJ of process electricity and 13.3 GJ of process heat, while 21.5 GJ of biomethane (430 kg) and 6 GJ of excess power would be generated simultaneously. By applying economic allocation, the fossil primary energy demand was estimated to 11.9 GJ per tonne oil.

CONCLUSIONS

Fossil primary energy demand for yeast oil in the four scenarios studied was estimated to be 10-38% lower than for the commonly used rapeseed oil and process energy demand could be met by parallel combustion of lignin residues. Therefore, feed oil can be produced from existing non-food biomass without causing agricultural expansion.

Life cycle environmental impacts of using food waste liquid fodder as an alternative for pig feeding in a conventional Cuban farm

This work aimed to compare cleaner production alternatives for pig production in the Cuban context through the Life Cycle Assessment (LCA) approach emphasizing the utilization of food waste (FW) as a substitute for traditional grain-based pig feeding. A conventional waste management method (lagooning) was assessed, including more environmentally friendly approaches (use of anaerobic digestion (AD) process); including the substitution of a fraction of solid fodder with food waste liquid fodder (LF), obtained from food waste. The analysis was based on one porcine equivalent livestock unit. The environmental impact categories assessed were global warming, terrestrial ecotoxicity, human carcinogenic toxicity, freshwater ecotoxicity, terrestrial acidification, and freshwater eutrophication. The major environmental benefits for pig production were observed when the maximum capacity of pigs was considered. In addition, favorable environmental performance was achieved by considering the substitution of solid fodder by LF, the AD as a waste management process, and the valorization of the solid and liquid effluents. The avoided products-related activities were the main contributor to freshwater ecotoxicity, human carcinogenic toxicity, and terrestrial ecotoxicity impact categories (up to 71 %). The sensitivity analysis showed that the variation in LF composition (protein concentration) could have a remarkable impact in all impact categories. Climate change performed as the more sensible impact category, suggesting that greenhouse gas (GHG) emissions, such as CO₂ and N₂O, are important drivers to change the environmental impact and need more attention. This research demonstrates that the environmental profile of the process can be improved by applying a cleaner production approach (AD as a waste management alternative and LF substituting solid fodder).

Suitability of operational N direct field emissions models to represent contrasting agricultural situations in agricultural LCA: Review and prospectus

N biogeochemical flows and associated N losses exceed currently planetary boundaries and represent a major threat for sustainability. Measuring N losses is a resource-intensive endeavour, and not suitable for ex-ante assessments, thus modelling is a common approach for estimating N losses associated with agricultural scenarios (systems, practices, situations). The aim of this study is to review some of the N models commonly used for estimating direct field emissions of agricultural systems, and to assess their suitability to systems featuring contrasted agricultural and pedoclimatic conditions. Simple N models were chosen based on their frequent use in LCA, including ecoinvent v3, Indigo-N v1/v2, AGRIBALYSE v1.2/v1.3, and the Mineral fertiliser equivalents (MFE) calculator. Model sets were contrasted, among them and with the dynamic crop model STICS, regarding their consideration of the biophysical processes determining N losses to the environment from agriculture, namely plant uptake, nitrification, denitrification, NH₃ volatilisation, NO₃ leaching, erosion and run-off, and N₂O emission to air; using four reference agricultural datasets. Models' consideration of management drivers such as crop rotations and the allocation of fertilisers and emissions among crops in a crop rotation, over-fertilisation and fertilisation technique, were also contrasted, as well as their management of the mineralisation of soil organic matter and organic fertilisers, and of drainage regimes. For the four agricultural datasets, the ecoinvent model predicted significantly lower values for NH₃ than AGRIBALYSE and STICS. For N₂O, no significant differences were found among models. For NO₃, ecoinvent and AGRIBALYSE predicted significantly higher emissions than STICS, regardless of the fertilisation regime. For both emissions, values of Indigo-N were close to those of STICS. By analysing the reasons for such differences, and the underlying factors considered by models, a list of recommendations was produced regarding more accurate ways to model N losses (e.g. by including the main drivers regulating emissions).

Eco-Friendly Feed Formulation and On-Farm Feed Production as Ways to Reduce the Environmental Impacts of Pig Production Without Consequences on Animal Performance

Animal feeding has a major contribution to the environmental impacts of pig production. One potential way to mitigate such effects is to incorporate an assessment of these impacts in the feed formulation process. The objective of this study was to test the ability of innovative formulation methodologies to reduce the impacts of pig production while also taking into account possible effects on growth performance. We compared three different formulation methodologies: least-cost formulation, in accordance with standard practices on commercial farms; multiobjective (MO) formulation, which considered feed cost and environmental impacts as calculated by life cycle assessment (LCA); and MO formulation, which prioritized locally produced feed ingredients to reduce the impact of transport. Ninety-six pigs were distributed between three experimental groups, with pigs individually weighted and fed using an automatic feeding system from 40 to 115 kg body weight. Based on the experimental results, six categories of impacts were evaluated: climate change (CC), demand in non-renewable energy (NRE), acidification (AC), eutrophication (EU), land occupation (LO), and phosphorus demand (PD), at both feed plant gate and farm gate, with 1 kg of feed and 1 kg of live pig as functional units, respectively. At feed level, MO formulations reduced CC, NRE, AC, and PD impacts but sometimes increased LO and EU impacts. These formulations reduced the proportion of cereals and oil meals into feeds (feed ingredients with high impacts), while the proportion of alternative protein sources, like peas, faba beans, or high-protein agricultural coproducts increased (feed ingredients with low impacts). Overall, animal performance was not affected by the dietary treatment; because of this, the general pattern of results obtained with either MO formulation at farm gate was similar to that obtained at feed level. Thus, MO diet formulation represents an efficient way to reduce the environmental impacts of pig production without compromising animal performance.

Sustainability and Pet Food: Is There a Role for Veterinarians?

Sustainability has become a watchword for a wide array of resource-intensive goods and services. This is promulgated by an increasing global population and concerns that natural resources and a hospitable climate will not be preserved for future generations. Life-cycle analysis is a tool that provides a framework to determine the magnitude products contribute to carbon emissions and depletion of natural resources. In this review, published research has been summarized to provide an overview of the impacts that pet food production and pet ownership have on the environment and the prospective role of veterinary practitioners in advocating for sustainability.

Measures Matter-Determining the True Nutri-Physiological Value of Feed Ingredients for Swine

Many types of feed ingredients are used to provide energy and nutrients to meet the nutritional requirements of swine. However, the analytical methods and measures used to determine the true nutritional and physiological ("nutri-physiological") value of feed ingredients affect the accuracy of predicting and achieving desired animal responses. Some chemical characteristics of feed ingredients are detrimental to pig health and performance, while functional components in other ingredients provide beneficial health effects beyond their nutritional value when included in complete swine diets. Traditional analytical procedures and measures are useful for determining energy and nutrient digestibility of feed ingredients, but do not adequately assess their true physiological or biological value. Prediction equations, along with ex vivo and in vitro methods, provide some benefits for assessing the nutri-physiological value of feed ingredients compared with in vivo determinations, but they also have some limitations. Determining the digestion kinetics of the different chemical components of feed ingredients, understanding how circadian rhythms affect feeding behavior and the gastrointestinal microbiome of pigs, and accounting for the functional properties of many feed ingredients in diet formulation are the emerging innovations that will facilitate improvements in precision swine nutrition and environmental sustainability in global pork-production systems.

The Reduction of Crude Protein with the Supplementation of Amino Acids in the Diet Reduces the Environmental Impact of Growing Pigs Production Evaluated through Life Cycle Assessment

Two experiments were performed to determine the digestibility of diets with crude protein (CP) reduction supplemented with amino acids (18.15; 17.15; 16.15 and 15.15%) to growing pigs (30–50 kg), to assess the use of nutrients and account for the manure excretion, and to evaluate the performance, backfat thickness, Longissimus lumborum depth, and plasma urea, aiming to evaluate the environmental impact through life cycle assessment (LCA); for the first time in Brazil interacting experiments were developed to evaluate the CP reduction and LCA. The CP reduction resulted in greater daily weight gain (p = 0.011), final weight (p = 0.020), better use of N and P, through the greater N and P retained (p = 0.003 and p = 0.017, respectively). There was a linear reduction in acidification potential (p = 0.015), eutrophication potential (p = 0.001), and land occupation (p = 0.005) when dietary CP decreased from 18.15 to 15.15%. The reduction in CP and supplementation of amino acids in diets for growing pigs (30–50 kg) improved final and daily weight gain. Through LCA, and performance and metabolism data, it was concluded that for the acidification, eutrophication and land occupation categories, impacts were reduced as the protein concentration was reduced.

Qualitative market segmentation of broiler grillers by using alternative proteins to soybeans and lipid sources in feeding programmes

1. The aim of the present study was to investigate increasing amount of n-3 fatty acids (FA) in common edible chicken meat cuts by testing different levels of extruded linseeds (LS) and rapeseed oil in growing and finishing diets. Another challenge was to replace a part of soybean meal by faba beans.2. For that purpose, 3168, one-day-old Hubbard JV15 strain chickens were distributed into six groups: R1 = control diet, R2 = 3% then 5% LS, R3 = 4% then 6% LS, R4 = 5% then 7% LS, R5 = 3% then 5% LS and a low amount of soybean meal in the finishing diet and R6 = 3% then 5% LS and no soybean meal in the finishing diet. The growing performance was recorded throughout the trial. At 30 days of age, all chickens were slaughtered in a commercial slaughter plant at an average weight of 1322 g, to mirror the production of low body weight 'broiler griller' birds commonly available for export markets. Thirty carcases per group were processed to determine cut yields. The edible parts from each half carcase were removed to determine the chemical composition and fatty acid composition of meat with skin. The sensorial quality of thighs was evaluated for 20 carcases per group, after roasting. The environmental and economic impacts of the feeding programmes were further evaluated.3. This study showed that it was possible to replace a part of the soybean meal in finishing diet by faba beans and to enrich meat with n-3 FA of broiler meat portions without altering growth performance, carcase composition and sensorial quality of meat. The environmental impact was reduced by these dietary interventions, whereby climate change parameters, expressed as kg CO2 eq./T, and phosphorus and fossil energy consumption were lower, but the land occupation was increased. The extra feed cost was +3 to +8% for groups fed R2 to R6 compared to the control group R1.

Economic and environmental assessments of combined genetics and nutrition optimization strategies to improve the efficiency of sustainable pork production

We evaluated the economic and environmental impacts of strategies that incorporated selection for pig feed efficiency and dietary optimization based on a single or multiple objectives tailored to meet the population nutritional requirements, with the goal to optimize sustainable farm feed efficiency. The economic and environmental features of the strategy were evaluated using life cycle assessment (LCA) and bio-economic models. An individual trait-based LCA model was applied to evaluate global warming potential, terrestrial acidification potential, freshwater eutrophication potential (EP), and land occupation of the combined genetics and nutrition optimization to produce 1 kg of live pig weighing 120 kg at the farm gate. A parametric individual trait-based bio-economic model was developed and applied to determine the cost breakdown, revenue, and profit to be gained from a 120-kg live pig at the farm gate. Data from two genetic lines with contrasted levels of feed efficiency were used to apply the combined genetics and nutrition optimization: accounting for the average nutritional requirements for each line, the individual pig responses to diets formulated for least cost, least environmental impacts, or minimum combination of costs and environmental impacts objectives were predicted with INRAPorc. Significant differences in the environmental impacts (P < 0.0001) and profit (P < 0.05) between lines predicted with the same reference diet showed that selection for feed efficiency (residual feed intake) in pigs improves pig production sustainability. When pig responses were simulated with their line-optimized diets, except for EP, all the line environmental impacts were lower (P < 0.05) than with the reference diet. The high correlations of feed conversion ratio with the environmental impacts (> 0.82) and the profit (< −0.88) in both lines underlined the importance of feed efficiency as a lever for the sustainability of pig production systems. Implementing combined genetics and nutrition optimization, the inherent profit and environmental differences between the genetic lines were predicted to be reduced from 23.4% with the reference diet to 7.6% with the diet optimized jointly for economic and environmental objectives (joint diet). Consequently, for increased pig sustainability, diet optimization for sustainability objectives should be applied to cover the specific nutritional requirements arising in the herd from the pigs genetic level.

Housefly Maggot Meal as a Potent Bioresource for Fish Feed to Facilitate Early Gonadal Development in Clarias gariepinus (Burchell,1822)

Food security is threatened by the global increase of human population, climate change, inequality of wealth distribution, the state of natural resources, peace and sustainability, among others. Aquaculture has become an important part of the food supply, hence contributing to food security. Sustainable fish production, which represents an important affordable protein supply, should therefore involve feed formulation and production techniques that are not dependent on fish meal as the protein source. It is on this basis that bioeconomy becomes very important to promote the resourceful use of biomass for feed, food, biomaterials, and bioenergy. This study presents housefly maggot meal as an efficient alternative protein source to fishmeal and a valuable bioresource. Clarias gariepinus fingerlings (male and female) were fed maggot meal supplemented diets for 24 weeks and we assessed their growth and gonadal development. The findings of this study revealed that maggot-meal-enhanced diets promoted growth and faster gonadal development in fish. Maggot meal represents a quality alternative protein source to fish meal and an excellent bioresource, which can help us attain sustainable aquaculture production.

Reducing environmental impacts of feed using multiobjective formulation: What benefits at the farm gate for pig and broiler production?

Feed production is the main contributor to several environmental impacts of livestock. To decrease environmental impacts of feed, those of feedstuffs should be considered during formulation. In particular, multiobjective feed formulation (MOF) can help reduce several environmental impacts simultaneously while keeping any increase in feed price moderate. The objective of this study was to assess environmental benefits of MOF at the farm gate for fattening pigs and broilers. For pigs, three feeding strategies were tested: classic 2-phase (2P), 2-phase with lower net energy content (2P-), and multiphase (MP). For broilers, two strategies were tested: classic 3-phase (3P) and 3-phase with higher digestible amino acid contents and lower metabolisable energy content (3P+). Diets were formulated using both least-cost formulation (LCF) and MOF, yielding six pig scenarios and four broiler scenarios. Environmental impacts at the farm gate were estimated using a modelling approach based on life cycle assessment. Indicators for six impact categories were then calculated: climate change (CC), cumulative non-renewable energy demand (CEDNR), acidification (AC), eutrophication (EU), land occupation (LO), and phosphorus demand (PD). As expected, MOF had lower farm-gate impacts than LCF (as much as -13%), but the degree of decrease varied by feeding strategy and impact. For pigs, MOF was equally effective in all strategies at reducing PD (-6 to -9%) and AC (-2%). In contrast, MOF was more effective in 2P and 2P- at decreasing CC (-5% to -7%), LO (-9% to -13%) and EU (-6% to -8%) than in MP (CC: -2%; LO: -4%; EU: -3%). The benefit of MOF was found greater in 2P (-7%) than in other pig strategies for CEDNR (-3 to +0%). For broilers, MOF was equally effective in both strategies tested at decreasing PD (-12%), AC (-2%), and EU (-4%). For CC and CEDNR, MOF was more effective in 3P (CC: -9%; CEDNR: -11%) than 3P+ (-6% for both impacts), but not for LO (+3% in 3P vs -1% in 3P+). These differences were due mainly to differences in animal performance (especially feed conversion ratio) among the strategies tested. Finally, in all scenarios, gross margin at the farm gate decreased with MOF comparatively to LCF (pigs: -3% to -11%); broilers: -7% to -11%). These results demonstrate the importance of comprehensive economic and environmental optimisation of feeding strategies by simultaneously considering feed impacts, animal performance, and manure management. To do so, further research is therefore required to develop new modelling tools.

Evaluating environmental impacts of selection for residual feed intake in pigs

To identify a proper strategy for future feed-efficient pig farming, it is required to evaluate the ongoing selection scenarios. Tools are lacking for the evaluation of pig selection scenarios in terms of environmental impacts to provide selection guidelines for a more sustainable pig production. Selection on residual feed intake (RFI) has been proposed to improve feed efficiency and potentially reduce the associated environmental impacts. The aim of this study was thus to develop a model to account for individual animal performance in life cycle assessment (LCA) methods to quantify the responses to selection. Experimental data were collected from the fifth generation of pig lines divergently selected for RFI (low line, more efficient pigs, LRFI; high line, less efficient pigs, HRFI). The average feed conversion ratio (FCR) and daily feed intake of LRFI pigs were 7% lower than the average of HRFI pigs (P < 0.0001). A parametric model was developed for LCA based on the dietary net energy fluxes in a pig system. A nutritional pig growth tool, InraPorc®, was included as a module in the model to embed flexibility for changes in feed composition, animal performance traits and housing conditions and to simulate individual pig performance. The comparative individual-based LCA showed that LRFI had an average of 7% lower environmental impacts per kilogram live pig at farm gate compared to HRFI (P < 0.0001) on climate change, acidification potential, freshwater eutrophication potential, land occupation and water depletion. High correlations between FCR and all environmental impact categories (>0.95) confirmed the importance of improvement in feed efficiency to reduce environmental impacts. Significant line differences in all impact categories and moderate correlations with impacts (>0.51) revealed that RFI is an effective measure to select for improved environmental impacts, despite lower correlations compared to FCR. Altogether more optimal criteria for efficient environment-friendly selection can then be expected through restructuring the selection indexes from an environmental point of view.

Effects of interactions between feeding practices, animal health and farm infrastructure on technical, economic and environmental performances of a pig-fattening unit

European pig production faces economic and environmental challenges. Modelling can help farmers simulate and understand how changes in their management practices affect the efficiency of their production system. We developed an individual-based model of a pig-fattening unit that considers individual variability in performance among pigs, farmers' feeding practices and animal management and estimates environmental impacts (using life cycle assessment) and economic results of the unit. We previously demonstrated that this model provides reliable estimates of farm performance for different combinations of management practices, pig types and building characteristics. The objectives of this study were to quantify how interactions between feeding practices and animal management influence fattening unit results in healthy or impaired health conditions using the model. A virtual experiment was designed to evaluate effects of interactions between feeding practices, health status of the pig herd and infrastructure constraints on the technical performance, economic results and environmental impacts of the unit. The virtual experiment consisted of 96 scenarios, which combined chosen values of 6 input parameters of the model: batch interval (35 days and 7 days), use or non-use of a buffer room to manage the lightest pigs, feed rationing (ad libitum and restricted) and sequence plans (two-phase (2P), daily-phase (DP)), scale at which the feeding plan is applied (i.e. room, pen and individual) and health status of the pig herd (i.e. healthy v. impaired). Variance analysis was used to test effects of the factors in these 96 scenarios, and multivariate data analyses were used to classify the scenarios. Healthy populations obtained on average higher economic results (e.g. gross margin of 11.20 v. 1.50 €/pig) and lower environmental impacts (e.g. 2.24 v. 2.38 kg CO2-eq/kg pig live weight gain) than the population with impaired health. With 35 days batch interval and DP feeding, populations with impaired health reached gross margin similar to healthy populations with 2P ad libitum feeding and 7 days batch interval. Restricted, DP and individual feeding plans improved the economic and environmental performances of the unit for both health statuses. This study highlighted that health status of the pig herd is the main factor that affects technical, economic and environmental performances of a pig-fattening unit, and that adequate feeding strategies and animal management can compensate, to some extent, the effects of impaired health on environmental impacts but not on gross margin.

The source of performance and excretion data affects the environmental impact of pig rearing estimated by life cycle assessment

The objective of this study was to calculate the environmental impact of raising pigs fed diets with 192, 182, 172, or 162 g kg−1crude protein (CP) from 15 to 30 kg live weight, using a life cycle assessment (LCA) based on either predicted or observed performance and excretion data. The predicted data were calculated for two animal profiles: one with feed intake and weight gain data being representative of the national Brazilian average (yp-AVG), and the other being representative of the specific experimental farm conditions (yp-SPC). Performance and excretion of pigs were either measured (yobs) or predicted (yp) for each CP scenario by using InraPorc®model and LCA impacts were calculated from these data. The ypand yobsdata of performance, nutrient excretion, and LCA were then compared using a Bayesian paired approach. Whatever the calculation methods, the decrease in dietary CP reduced the environmental impacts per kilogram of weight gain on acidification potential (AP), eutrophication potential (EP), and land occupation. Predicted data from yp-SPCdid not differ from yobsdata except for nitrogen excretion and AP and EP impacts. Predicted data from yp-AVGdiffered from yobsfor all criteria except for body weight gain, phosphorus excreted, and cumulative energy demand, mainly because of the lower feed conversion ratio for average data. It was concluded that the use of predicted data calculated from specific farm indicators could better explain the environmental impact of pig farming in Brazil compared with the use of national average indicators.

Life Cycle Assessment of Iberian Traditional Pig Production System in Spain

Traditional Iberian pig production is characterized by outdoor systems that produce animals fed with natural resources. The aim of this study was to assess the environmental impacts of such systems through Life Cycle Assessment. Environmental impacts were analysed per kilogram of live weight at farm gate. Iberian pig production in montanera had the lowest impacts for climate change (CC), acidification (AC), eutrophication (EU) and cumulative energy demand (CED), being 3.4 kg CO2 eq, 0.091 molc H+ eq, 0.046 kg PO43− eq, and 20.7 MJ, respectively, due to the strict use of natural resources (acorns and grass) during the fattening period. As Iberian farms had a greater dependence on compound feed in cebo campo, environmental impacts on CC, AC, EU and CED were 22, 17, 95 and 28% higher, respectively, than with montanera. For land occupation (LO), however, cebo campo had a lower impact (31.6 m2·year) than montanera (43.0 m2·year) system. Traditional Iberian pig production systems have environmental impacts higher than conventional systems studied in literature but are similar to other traditional systems. Based on the present assessment, it is necessary to account for the contribution of emissions resulting from the consumption of natural resources to avoid the underestimation of environmental impacts.

Multiobjective formulation is an effective method to reduce environmental impacts of livestock feeds

Environmental and economic performances of livestock production are related largely to the production of complete feeds provided on commercial farms. Formulating feeds based on environmental and economic criteria appears a suitable approach to address the current challenges of animal production. We developed a multiobjective (MO) method of formulating feed which considers both the cost and environmental impacts (estimated via life cycle assessment) of the feed mix. In the first step, least-cost formulation provides a baseline for feed cost and potential impacts per kg of feed. In the second, the minimised MO function includes normalised values of feed cost and impacts climate change, P demand, non-renewable energy demand and land occupation. An additional factor weights the relative influence of economic and environmental objectives. The potential of the method was evaluated using two scenarios of feed formulation for pig, broiler and young bulls. Compared to baseline feeds, MO-formulated feeds had lower environmental impacts in both scenarios studied (−2 to −48 %), except for land occupation of broiler feeds, and a moderately higher cost (1–7 %). The ultimate potential for this method to mitigate environmental impacts is probably lower than this, as animal supply chains may compete for the same low-impact feed ingredients. The method developed complements other strategies, and optimising the entire animal production system should be explored in the future to substantially decrease the associated impacts.

Phytase supplementation in diets rich in fiber from rapeseed enhances phosphorus and calcium digestibility but not retention in broiler chickens

Two experiments were conducted on broilers to assess the effect of dietary fiber from 00-rapeseed meal (RSM) on phosphorus (P) and calcium (Ca) apparent ileal digestibility (AID) and retention (AR) during the growing (Exp1: 10 to 21 d) or finishing period (Exp2: 21 to 31 d) in diets supplemented or not with microbial phytase. Each experiment involved 144 male Cobb 500 fed one of 8 diets. Fiber content was modulated by incorporating whole RSM, RSM from dehulled rapeseeds, either raw or supplemented with 2 levels of defatted rapeseed hulls. Diets were supplemented or not with 750 phytase units of microbial phytase per kg. Excreta were collected from d 14 to d 17 (Exp1) and from d 27 to d 30 (Exp2) to measure AR. At the end of experiments, digestive tracts were sampled and weighed. The distal ileum and tibias were collected to measure AID and bone mineralization, respectively. Age did not significantly alter the response of birds to the addition of dietary fiber. Inclusion of hulls decreased growth performance (P < 0.05). The weight of the proventriculus-gizzard (PG) increased with the dietary fiber content in Exp1: The decreased weight observed using dehulled RSM was reversed following the inclusion of hulls. In both trials, while the presence of phytase increased the AID of P (P < 0.001) but not Ca, the inclusion of hulls with phytase improved the AID of P and Ca [linear (Lin), P < 0.05]. This effect could depend on the effect of fiber on PG development and physiology. Hulls decreased the moisture content of excreta (P < 0.01), suggesting higher water retention or lower water consumption with fiber. The AR of P was lower than AID of P with hulls, contrary to Ca, suggesting a metabolic imbalance. The decrease of AR together with the decrease of bone characteristics indicates a lack of Ca in diets with hulls and suggests that P and Ca provision should be adapted to the level and the origin of fiber inclusion.

Modelling interactions between farmer practices and fattening pig performances with an individual-based model

European pig production continues to encounter economic and environmental challenges. To address these issues, methods have been developed to assess performances of pig production systems. Recent studies indicate that considering variability in performances among pigs improves the accuracy and reliability of results compared with modelling an average animal. Our objective was to develop a pig fattening unit model able to (i) simulate individual pig performances, including their variability in interaction with farmers' practices and management, and (ii) assess their effects on technical, economic and environmental performances. Farmer practices included in the model were chosen from a typology generated from on-farm surveys focused on batch management, pig allocation to pens, pig feeding practices, practices of shipping to the slaughterhouse, and management of the remaining pigs. Pigs are represented using an individual-based model adapted from the InraPorc® model. To illustrate the model's abilities, four scenarios were simulated that combine two feed rationing plans (ad libitum, restricted to 2.5 kg/day) and two feed sequence plans (two-phase, 10-phase). Analysis of variance was performed on the simulated technical, economic and environmental indicators (calculated via Life Cycle Assessment). The feed rationing plan and feed sequence plan significantly affected all indicators except for the premium per pig, for which the feed sequence plan did not have a significant effect. The 'restricted 10-phase' scenario maximised gross margin of the fattening unit (14.2 €/pig) and minimised environmental impacts per kg of pig produced. In contrast, the 'ad libitum two-phase' scenario generated the lowest margin (8.20 €/pig) and the highest environmental impacts. The model appears to be a promising tool to assess effects of farmers' practices, pig characteristics and farm infrastructure on technical, economic and environmental performances of the fattening unit, and to investigate the potential of improvement. However, further work is needed, based on virtual experiments, in order to evaluate the effects of a larger diversity of practices.