Climate Smart Norwegian Sheep Production

Norway has large unused outfield resources. The political goal of increased domestic food production based on national resources in line with population growth necessitates the use of these outfields by grazing ruminants. At the same time, the agriculture sector is committed to reduce its greenhouse gas (GHG) emissions. The challenge is thus to increase ruminant production based on outfield grazing while simultaneously reducing GHG from livestock. Scientific knowledge of the level and variation in GHG emissions from Norwegian sheep production is currently lacking. This project aims to contribute to a sustainable, climate smart sheep production based on utilization of national feed resources, including outlying pastures, with lowest possible climate impacts. The project goals will be reached by developing a farm-scale model for the estimation of GHG emissions from Norwegian sheep production. The whole-farm model, HolosNorSheep, is based on collected data from various sources (e.g. Sheep recording System (SRS), Account results etc.) to ensure relevance for Norwegian conditions. The model is dynamic to be able to account for the variation between farms, e.g., in natural resources, pasture- types and periods, animal performance and different lamb slaughter groups etc. HolosNorSheep includes several sub-models to calculate GHG emissions from various sources. Enteric methane is calculated from feed intake estimated using a planning tool developed by the advisory service (Nortura). Methane and nitrous oxide emissions from storage and spreading of animal manure are calculated using the methodology in the national inventory. Other included emissions sources are nitrous oxide from the use of fertilizers, use and production of input factors (such as concentrates, fuels and fertilizers) and soil carbon balance. HolosNorSheep estimates the total on farm GHG emissions, additionally GHG are also allocated per kg of co-products (lamb and sheep carcass and wool) (i.e., emission intensities). Emission intensities per kg carcass calculated for five geographical regions (East, West, South, Mid and North) based on average account results (e.g., herd size, weights, number of lambs, use of input factors, manure handling systems etc.) varied substantially from 20 (Mid) to 24 kg CO2-equivalents/kg (North) (economic allocation). The corresponding values for wool were 17 and 20 kg CO2-equivalents/kg. Enteric methane was the most important emission source (44-51%), followed by soil nitrous oxide (15-19%). The difference between North and Mid is mainly related to higher use of fuels and N-fertilizer in North, related to the natural conditions (i.e., shorter growing season and only one cut). This results in a lower gras yield and thus a need for a larger ley area. Weighted average emission intensities for carcass and wool, based on the geographical distribution of sheep, was estimated to 21 and 18 kg CO2 equivalents/kg, respectively. HolosNorSheep is now being facilitated as a Climate calculator in cooperation with Landbrukets Klimaselskap and will be used as a on farm tool by the advisory services. HolosNorSheep is currently being applied to 32 test-farms, with large variation in geographical location, animal performances and natural conditions. Most test-farms have several years of data (2-3 years). Initial data analyses show large variations in emission intensities between farms. Based on the results, factors related to animals and management that are of relevance for on-farm GHG emissions will be identified. Finally, the model will be used to compare alternative production systems for sheep related to breeds, concentrates, roughages, pastures etc., related to resource use and emissions intensities. The result will be used as a basis for choosing mitigation strategies to reduce the environmental impact of Norwegian sheep production. Some preliminary analyses include variation in silage quality, manure handling systems, age at first lambing and no. of weaned lambs per ewe. A comparison between the average performance in SRS with the best performing third for number of born lambs and lamb mortality shows that the emission intensity per kg carcass can be reduced with 4%. Similarly, 10% increased lamb growth rate can reduce emission per kg carcass with 5%. A combination of these measures can reduce the emission intensity with 9%. Other alternative production systems will be selected in cooperation with the project partners. HolosNorSheep is also used in the project “Grass to Gas” (Strategies to mitigate GHG emissions from pasture-based sheep systems) financed by JPIFACCE- Agriculture, Food Security and Climate Change. In “Grass to Gas”, two different breeds are compared: the Norwegian White Sheep (NWS) and the Old Norwegian Spæl (ONS). These breeds vary considerable with respect to size and the number of weaned lambs per ewe. The calculations with HolosNorSheep revealed that NWS have lower emission intensities per kg carcass

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Norway has set political goals to increase domestic food production based on domestic resources in line with the population growth, while at the same time reducing the greenhouse gas (GHG) emissions from agriculture (currently 8% of total domestic GHG emissions). The agricultural area is small, 3% of the total land area. Cereals are only grown on one-third of this area, due to constraints in climate and topography. The rest of the area (66%) is cultivated grass production. In addition, substantial valuable feed resources are located in outfields, i.e. uncultivated vegetation in the forests and mountains. These areas (140 000 square km) represent a 50% unexploited grazing capacity, corresponding to 3.6 million sheep. Thus, utilization of natural feed resources is inevitably related to ruminant livestock, which is a challenge in relation to reducing GHG emissions. This project aims to contribute to a sustainable, climate smart sheep production based on exploitation of national feed resources, including outlying pastures, combined with lowest possible climate impacts. The project goals will be reached by developing a farm-scale model for the estimation of GHG emissions from Norwegian sheep production.Further, the model will be used as a tool to identify factors related to animals and management that are of relevance for the on-farm GHG emissions. This can be used as a basis for mitigation options to reduce the environmental impact of the sheep meat production. Finally, the project will examine how alternative sheep production systems will affect GHG emissions and use of resources, and recommend mitigation strategies to reduce GHG emissions from Norwegian sheep farms.