Abstract
The fibrous residue left after the extraction of leaf protein from broad bean (Vicia faba L.) was ensiled, and its food value was examined in digestion and nitrogen balance trials using sheep fed only the silage at 2.0% level of dry matter per kg body weight. The results obtained as follows ; 1. The digestibilities of organic matter, crude fat and NFE were significantly higher in silage feeding than in feeding of timothy hay as a control ration. The digestibility of crude protein, howevre, was significantly lower in silage feeding. 2. The urinary nitrogen excretion was high in silage feeding compared with that in hay feeding, and it was reduced in the feeding of silage plus hay (1:1/D.M.). As a whole, the retained nitrogen was similar in both feedings of silage and silage plus hay. Consequently, the net utilization of dietary nitrogen was the highest in silage plus hay feeding. 3. The concentrations of ruminal ammonia and VFAs were higher in silage feeding than in feeding of hay with or without silage. This might show a high ruminal fermentation after the silage feeding in sheep. 4. The blood glucose level was almost similar in both feedings of silage and hay. The concentration of plasma total protein was similar in all feedings of silage, hay and silage plus hay. The level of blood urea-nitrogen was higher after silage feeding than after hay or silage plus hay feedings. From the results described above, it is concluded that the silage made from a fibrous residue of broad bean, when used as roughage by sheep was some what superior in food value to timothy hay, and it is also suggested that nitrogen utilization of the silage may be efficiently improved by using hay jointly at the same time.
