Ensiling characteristics, ruminal nutrient degradabilities and whole tract nutrient utilization of berseem clover (Trifolium alexandrinum L.) silage

Abstract

A study was conducted to determine ensiling characteristics and nutrient utilization by ruminants of berseem clover silage (BCS). Ensiling characteristics were determined by ensiling forage in mini-silos for 0, 2, 4, 8, 16 and 70 d. Two lactating Holstein cows fitted with ruminal cannulas were utilized to determine ruminal nutrient degradabilities while six ram lambs were used to determine total tract nutrient digestibilities. Ruminal and whole tract nutrient utilization of BCS were compared with those of alfalfa silage (AS). Results showed that BCS went through a rapid fermentation as shown by a significant (P < 0.05) reduction in pH during the first 2 d post-ensiling. Most of the proteolytic activity took place between day 0 and day 2 as indicated by a reduction (P < 0.05) in true protein and neutral detergent insoluble protein and an increase (P < 0.05) in non-protein nitrogen. Relative to AS, BCS had a similar ruminal degradability of dry matter (DM), a lower degradability of crude protein (CP), and a higher (P < 0.05) degradability of neutral detergent fiber (NDF). Relative to AS, BCS had a higher (P < 0.05) whole-tract digestibility of DM (70.7 vs. 66.0%), organic matter (71.5 vs. 65.9%), NDF (65.6 vs. 54.5), acid detergent fiber (64.6 vs. 54.6) and gross energy (69.6 vs. 64.0), but a lower (P < 0.05) wholetract digestibility of CP (69.2 vs. 75.9%). These results suggest that BSC could replace AS as a forage source for ruminants. Key words: Berseem clover silage, ruminal degradability, total tract nutrient utilization