The effect of cereal incorporation on the fermentation of spring-and autumn-cut silages in laboratory silos

The effect of adding ground oats and barley on the ensiling characteristics of autumn-and spring-harvested ryegrass was studied in laboratory scale silos.
The addition of oats or barley at rates of 13 or 53 kg t⁻¹ of grass significantly improved the fermentation of late autumn ryegrass silage in the first year. Ammonia N levels were reduced from over 20% of total N to 11% or less. Similar addition to autumn-cut ryegrass higher in soluble carbohydrate content in the second year also significantly reduced pH and ammonia levels but all silages were well fermented. Addition of cereals to spring-cut ryegrass containing over 20% soluble carbohydrate had no effect on fermentation. Cereal addition increased silage DM and decreased silage fibre content in all experiments.
The results are discussed in relation to the potential advantage of cereal addition in the ensiling of grass crops.