Potential of Cull Banana Fruit at Two Maturity Stages as a Feed Supplement for Cattle: Effects on In Vitro Ruminal Fermentation, Kinetics of Gas Production and Digestibility

An in-vitro study was conducted to characterize the nutrient profile of banana fruit and peel at two stages of maturation, as well as its effects on ruminal fermentation parameters, kinetics of gas production, and digestibility when used as livestock feed. Substrates included whole green fruit and peel (GF), green peel (GP), ripe peel (RP), whole ripe fruit and peel (RF), and kikuyo grass (KG), with KG characterized due to utilization in regions of banana production. Digestibility (P < 0.01) was greatest in RF compared with KG, and maximal gas production (P < 0.01) was greatest in GF and RF compared with KG and RP. Lag time of fermentation (P < 0.01) for banana substrates did not differ, however, more time was required for KG. Methane production (P < 0.01) and concentration of ammonia nitrogen (P = 0.02) was greatest in GF and RF; however, production of hydrogen sulfide (P = 0.04) was greatest in KG and GF, with GF similar to remaining substrates. A decrease in pH (P < 0.01) was observed in banana substrates compared with KG, with RF and GF having decreased acetate (P < 0.01) but increased butyrate (P = 0.02) molar proportions. Maturity of banana substrates did not affect ruminal fermentation; however, banana fruit fermentation was similar to concentrate diets. Supplementation of rejected banana waste as feedstuff for livestock provides a viable source of energy to the rumen, thus decreasing competition between human and livestock for land use and consumption. Graphic Abstract: [Figure not available: see fulltext.]