Abstract
The first limiting nutrient for sheep at maintenance receiving poor quality hay is rumen degradable protein (RDP), and addition of urea can substitute part of the RDP (Köster et al., 1997). However, urea is highly soluble and can cause rapid increases in rumen ammonia (NH3-N) concentrations. The aim of this study was to determine whether a slow release nitrogen (N) source (Optigen II) can be substituted in place of a rapid release N source (urea) without having any negative effects on intake, digestibility, rumen fermentation and microbial protein synthesis when the sheep are fed poor quality roughage.
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Acknowledgments
The authors would like to acknowledge the national research foundation (NRF) and the international foundation for science (IFS) for providing research grant to cover the running cost of this study.
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Mentz, A.M., Hassen, A., Van Niekerk, W.A., Mynhardt, H., Coertze, R. (2013). The effect of substituting urea for a commercial slow release urea as supplement to sheep fed a poor quality Eragrostis curvula hay. In: Oltjen, J.W., Kebreab, E., Lapierre, H. (eds) Energy and protein metabolism and nutrition in sustainable animal production. Energy and protein metabolism and nutrition in sustainable animal production, vol 134. Wageningen Academic Publishers, Wageningen. https://doi.org/10.3920/978-90-8686-781-3_23
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DOI: https://doi.org/10.3920/978-90-8686-781-3_23
Publisher Name: Wageningen Academic Publishers, Wageningen
Online ISBN: 978-90-8686-781-3
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