Nutritional characterization of banana by-products under irrigation (In case of Arba Minch, South Ethiopia)

The present study evaluated the nutritional values of banana by-products (BBP) obtained from irrigated areas of Arba minch, Gamo Zone Southern Ethiopia. By-product fractions (leaf, shoot, rhizome, fruit bunch and whole mixture) were collected from farmers' gardens during fruit harvesting. Collected fractions were separately chopped and air-dried in shades lined with plastic sheets until transported to Hawassa University, Animal Nutrition Laboratory, where chemical composition and existence of associative effects were evaluated using an in vitro system. The dry matter (DM) content of BBP was 18.5, 7.6, 8.3, 6.2 and 10.2% for leaves, pseudostem, rhizome, FB-stem and whole mixture, respectively. The CP values obtained ranged from 2.5 to 8.6%, the lowest for the pseudostem, while the highest was for the leaf. The IVDMDs of leaves, pseudostem, rhizome, FB-stem, and the whole BBP mixture were 35.5, 41.3, 35.4, 46.21, and 39.6%, respectively. Potential gas production (a+b) was rated highest for Wmix (41.3 ml) and rhizome (40.0 ml) and lowest for leaf (18.8 ml). The ranges of metabolisable energy (ME), organic matter digestibility (OMD) and short-chain fatty acids (SCFA) values were 2.7 to 4.5 MJ/kg dry weights, 29.26 to 33.27% and 0.22 to 0.33 µmol, respectively. ME, OMD and SCFA values ranked as, pseudo stem > Wmix > rhizome > Fb stem > leaf. The higher values obtained for potential gas production (a+b), ME, OMD and SCFA in pseudostem and Wmix could mean higher availability of nutrients for rumen microorganisms. The results showed that pseudostem and Wmix could have higher nutritional value in ruminant feed than other fractions, but appropriate treatment/supplementation with high-quality feed or additives is needed to balance nutrients.