Publikasjoner
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2024
Sammendrag
Housing and indoor feeding of sheep is required throughout the cold season, which can last more than half a year, in Nordic highlands and Alpine regions. This study aimed to examine and evaluate the housing costs, including labour requirements, according to type of sheep housing system and degree of mechanized feeding by investigating systems commonly used in Nordic and Alpine regions. Detailed cost data were obtained from 61 surveyed sheep farmers in Norway with sheep houses built between the years 2008 and 2015. Costs were calculated for a baseline scenario (2021-prices) as well as for five scenarios at low and high discount rates and opportunity cost of labour, and high energy prices. The median (interquartile range) flock size was 150 (100) winter-fed sheep. Houses with slatted floors were more expensive than deep-litter systems. Costs of bedding material and feed waste were however higher, and the net value of the manure were lower in houses with deeplitter systems. At the baseline assumptions, overall net housing costs per sheep was not statistically different among the main housing types studied. Multiple regression analyses showed that net housing costs per sheep were lower in larger flocks and for centrally located farms (control variables). Undertaking daily chores, such as feeding of roughages twice a day rather than once, resulted in significantly higher net housing costs. Mechanized feeding of roughages, and even more so for concentrates, were not economically justified since labour savings were not sufficient to pay for the additional capital costs. A round bale chopper lowered net housing costs, significantly at a high labour cost. None of the scenarios found slatted floors to be significantly more expensive than deep-litter systems. High costs of labour and capital favoured deep-litter systems, while slatted floor systems were more advantageous at rising prices of energy that resulted in increased values of organic manures and costs of feed wastes and bedding materials. The study was based on a decade old data from common Norwegian sheep house variants. Farmers that consider constructing a new sheep house today, still must compare these variants as their main alternatives. We encourage other researchers to include effects of housing systems and mechanized feeding on animal performance, health, and welfare. Moreover, future studies should preferably also be undertaken in other environmental or socio-economic settings to produce more general results.
Sammendrag
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Forfattere
Akhil Reddy Pashapu Sigridur Dalmannsdottir Marit Jørgensen Marian Schubert Odd Arne Rognli Mallikarjuna Rao KoviSammendrag
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Forfattere
Mekjell Meland Oddmund Frøynes Milica Fotirić Akšić Naris Pojskić Belma Kalamujić Stroil Merima Miralem Almira Konjić Fuad GasiSammendrag
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Sammendrag
To facilitate nutrient management and the use of manure as a feedstock for biogas production, manure is often separated into a solid and a liquid fraction. The former fraction is usually high in P and low in N, so when incorporated in the soil as fertilizer, it needs to be supplemented by N from, e.g., mineral fertilizers or nitrogen-fixing species. To explore strategies to manage N with solid-separated manure, we examined how the amount of digestate and the N:P ratio of pig digestate, i.e., manure that had partially undergone anaerobic digestion, affected the productivity of Westerwolds ryegrass and red clover in a pot experiment with one soil which was rich and another which was poor in plant nutrients. The soil and plant species treatments were combined with four doses of digestate, which gave plant available phosphorus (P) concentrations of 2, 4, 8, or 16 mg P100 g−1 soil. Ammonium nitrate was dosed to obtain factorial combinations of digestate amount and N:P ratios of 1.8, 4, 8, and 16. Clover was harvested once at the beginning of flowering (15 weeks after seeding), while Westerwolds ryegrass was allowed to regrow three times after being cut at the shooting stage (in total, 4 cuts, 6, 9, 12, and 15 weeks after seeding). Ryegrass yield increased by up to 2.9 times with digestate dosage. Interactions with the N:P ratio and soil type were weak. Hence, the effect of increasing the N:P ratio was additive across digestate dosages. Red clover biomass also increased by up to 39% with digestate dosage. Residual nutrients in the soil after red clover cultivation were affected by the initial differences in soil characteristics but not by digestate treatment or biomass of harvested red clover. A targeted N management is required to benefit from the P-rich digestate in grass cultivation, while the long-term effects of red clover culture on N input need further investigation.
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