Effects of Different Parts on the Chemical Composition, Silage Fermentation Profile, In Vitro and In Situ Digestibility of Paper Mulberry

Abstract

Paper mulberry (Broussonetia papyrifera, PM) is high protein but unutilized as a feed source. The study explores the different parts (leaf, stem, and whole plant) of PM chemical composition, silage fermentation, and in vitro and in situ digestibility, aiming to give some guidelines to PM usage as feed. The result showed that the leaf had a higher fresh weight than the stem (p < 0.05). The dry matter contents of the three groups had no differences. The highest crude protein, ether extract, water-soluble carbohydrate, ash, calcium, phosphorus, amino acid contents, and butter capacity were observed in the leaf (p < 0.05). The stem had the highest (p < 0.05) neutral detergent fiber, acid detergent fiber, and lignin contents. After ensiling, the stem silage had the lowest pH value, ammonia nitrate (NH3-N), lactate, acetate, and propionate (p < 0.05). The leaf silage had the highest pH value (p < 0.05). The lactate, acetate, and propionate in the leaf and whole plant silage had no difference. The butyrate was not detected in all silage. The in vitro and in situ digestibility experiments showed the leaf had the highest digestibility (p < 0.05), which could produce more volatile fatty acids and have a higher effective digestibility. These results allow a greater understanding of PM to be used as a feedstuff.