Amazing Grazing: N use efficiency of 60 individual dairy cows under intensive grazing
| Autor: | Klootwijk, C.W., Zom, R.L.G., van den Pol, A., van Middelaar, C.E., Holshof, G., de Boer, I.J.M. |
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| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: | |
| Zdroj: | Sustainable meat and milk production from grasslands. Wageningen Academic Publishers Sustainable meat and milk production from grasslands |
| Popis: | The Dutch dairy sector aims to improve nitrogen (N) use efficiency (NUEN) of intensive dairy farms while supporting grazing. To gain insight into the NUEN of intensive dairy farms, we need insight into the NUEN at cow level. We performed a 2 x 2 factorial grazing trial with 60 Holstein Friesian cows (7.5 cows ha-1), in which we compared NUEN of individual cows under two grazing systems, i.e. compartmented continious grazing (CCG) and strip grazing (SG) and two levels of dietary rumen-degradable protein balance (OEB), i.e. low and high (a difference of 500 g OEB cow-1 day-1). Grass and supplementary intakes and faecal and milk outputs were quantified and analysed for N content, during two weeks in July and September 2016. Results showed a higher NUEN for cows in CCG (39%) compared to cows in SG (36%) in July, due to lower grass (N) intake in CCG. Low OEB showed a higher NUEN (40%) compared to high OEB (34%). Our results are key to exploring strategies to improve NUEN of farms that apply innovative grazing systems. |
| Databáze: | OpenAIRE |
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