Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2019
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Authors
Luc Graamans Isabella Righini Bram Vanthoor Michel Verheul Muhammad Naseer Henk Maessen Tomas Persson I. Tsafaras Cecilia StanghelliniAbstract
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Authors
Isabella Righini Bram Vanthoor Michel Verheul Muhammad Naseer Henk Maessen Tomas Persson I. Tsafaras Cecilia StanghelliniAbstract
No abstract has been registered
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Michel VerheulAbstract
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Gunnhild SøgaardAbstract
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Klaus MittenzweiAbstract
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Klaus MittenzweiAbstract
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Abstract
An annual sheep production system in Norway incorporates grazing natural pastures for five months. Yet no measurements of enteric methane emissions from grazing sheep have been performed under Norwegian conditions. A pilot study was conducted with 12 Norwegian White ewes to test the feasibility of using the sulphur hexafluoride (SF6) tracer technique under Norwegian conditions. The ewes were split onto one of two pastures, mixed grass (Bromus inermis dominated, Poa pratensis, Festuca pratensis) or white clover (Trifolium repens). After five days adaptation to pastures, breathe samples were collected into evacuated one L PVC canisters over three consecutive days where capillary tubes (0.38 to 0.42 mL/min initial flow) restricted flow. Gas samples were analysed by gas chromatography. Feed intakes were not recorded. Average live weights were 64 kg and 66 kg for ewes on grass and clover pastures, respectively. Methane emissions were 23.9 g/d from sheep on mixed grass and 28.2 g/d for sheep on white clover. Methane emissions were not correlated (p=0.33) to ewe live weight. One explanation for the 15% difference in methane emission could be differences in feed intake. The few days of sample collection could also explain some of the observed difference since the technique is recommended to be used over five days to reduce errors in observations. This pilot study shows that using the SF6-technique is a feasible method for future research. More experiments measuring enteric methane emission over a longer period from grazing sheep and cattle under Norwegian conditions are planned for the future.
Authors
Anna Birgitte MilfordAbstract
No abstract has been registered