Submitted to: International Silage Conference
Publication Type: Proceedings
Publication Acceptance Date: 1/2/2012
Publication Date: 7/3/2012
Citation: Marita, J.M., Hatfield, R.D., Brink, G.E., Mertens, D.R. 2012. Co-ensiling temperate grasses to improve protein use efficiency in ruminants. In: Proceedings of the XVI International Silage Conference, July 2-4, 2012, Hameenlina, Finland. p. 132-133. Interpretive Summary:
Technical Abstract: Preserving high-quality forage in cool humid regions of agricultural production remains a challenge due to potentially high levels of protein degradation during ensiling. Some forages such as red clover produce high levels of polyphenol oxidase (PPO) and o-diphenols to effectively inhibit proteolysis during the ensiling process. Previous work has shown that some temperate grasses (i.e., orchardgrass and smooth bromegrass) contain high levels of polyphenol oxidase, but not sufficient levels of o-diphenol substrates to inhibit proteolytic activity during ensiling. Other grasses such as tall fescue and timothy contain high levels of o-diphenols, but no PPO activity. Experiments were carried out to evaluate the feasibility of co-ensiling a PPO grass with one that contains high levels of o-diphenol substrates. Forages were cut, wilted to the appropriate moisture level, chopped, and macerated before ensiling in plastic-wrapped bales. Ensiled treatments contained single forages (controls) and mixtures of a PPO grass with an o-diphenol grass. After a minimum of thirty days of ensiling, silage bales were opened and fed to young lambs. Total feed intakes by individual lambs were measured, as well as their total feces and urine excretion. Protein use efficiency (crude protein metabolizability [CPM] and % of protein consumed and retained by the lambs) was calculated for each feeding trial. Ensiling a PPO grass with an o-diphenol grass increased CPM by 25 to 90%, depending upon the grass combinations. This work would indicate that co-ensiling grasses could be beneficial in preserving protein and increasing animal performance.