Degradation of Duckweed Protein in the Rumen of Sheep

Degradation of plant N in the rumen results in the formation of ammonia-N and NAN. Rumen bacteria utilise these breakdown products to synthesise their cell proteins. This study was carried out to investigate the in vivo degradation of N-labelled duckweed in the rumen and the utilisation of the degradation products by rumen bacteria. We found that duckweed protein was relatively resistant to rumen degradation, and therefore concluded that duckweed provides a potentially useful source of ‘escape’ protein for sheep. The results also indicated that plant N breakdown products more complex than ammonia-N were extensively assimilated by rumen bacteria. An appreciable intra-ruminal N recycling (48% of N intake) occurred in the sheep in this study.