Influence of chemical, enzymatic and phytogenic ensiling preparations on digestibility, degradability and PDI and NEL content of lucerne and red clover

Lucerne and red clover cut at the beginning of the flowering stage were conserved by chemical (formic acid; Na-formiate; Ca-propionate), enzymatic (based on cellulases, hemicellulases, amylases and glucose oxidases, including microbial inoculants) or phytogenic (plant oils) preparations. The effective degradability of crude protein (CP) was measured in two steers with rumen cannulas, intestinal digestibility of the undegraded protein (UDP) in two cows equipped with duodenal T-cannulas, and the apparent CP and organic matter (OM) digestibility in eight wethers. The PDI (protein digestible in the intestine) and NEL (net energy of lactation) were calculated using the above mentioned values. The differences among ensiling preparations were significant both in lucerne and clover, regarding CP effective degradability (P < 0.01), PDI (P < 0.01), and NEL (P < 0.05). CP effective degradability of red clover preserved with the enzymatic or phytogenic preparations was higher (P < 0.01) compared with the chemical agents. The mean of all PDI values of red clover ensiled with the phytogenic preparations did not differ (P > 0.05) from that of PDI values of chemically conserved clover. The UDP intestinal digestibility of the lucerne conserved by the chemical or enzymatic preparations was higher (P < 0.01) than that of clover. The difference in the UDP intestinal digestibility between samples conserved with formic acid or the enzymatic preparation was not proved (P > 0.05) either in the lucerne or in the red clover. Formic acid was recommended as the best preparation for ensiling lucerne and red clover regarding PDI and NEL content.