Valorization of Agro-Industrial Waste of Cajanus cajan Shell, Plantain Peels (Musa spp.) and Zea mays Cob Husk on Rumen Degradation Kinetics and Mitigation of Greenhouse Gases Production in Ruminants

The aim of this research was to evaluate the effect of agro-industrial waste from C. cajan shell, plantain peels (Musa spp.), and Zea mays cob husk on in situ ruminal degradation kinetics and in vitro gas production. Rumen degradation of DM in the soluble fraction (A) was higher (p = 0.0001) in plantain peel (37.5%). The insoluble but potentially degradable fraction (B) was higher (p = 0.0001) in C. Cajan shell (71.7%). Regarding the degradation rate in percentage per hour (c: 0.13%/h), degradation potential (A + B: 86.3%) and effective degradation at the different passage rates (k) (0.02: 79.6%, 0.05: 72.4%, and 0.08: 67.3% k, respectively), it was higher (p < 0.05) in the plantain peels. Rumen NDF degradation was higher (p < 0.05) in plantain peels for all degradation parameters (A + B: 80.8, k: 0.02: 57.1%, 0.05: 44.9%, and 0.08: 37.6%, respectively). Total gas production kinetics (D; 333.3 mLgas/0.5 g degraded DM) and gas production at 24, 48, and 96 h were lower (p = 0.0001) in plantain peels. CH4 production was low (p = 0.0001) in plantain peels at all evaluated times (24 h: 32.7, 48 h: 37.9, and 96 h: 53.5 mL/0.5 g degraded DM). CO2 production was lower (p < 0.05) in C. Cajan and plantain peels at all evaluated times. Under the conditions of this study, it can be concluded that the use of plantain peels (Musa spp.) can be beneficial to animals when incorporated into the diet, as it contains a similar protein content to tropical forages, as well as low fiber content, high ruminal degradation, and secondary compounds that benefit energy maximization by mitigating enteric gas production in ruminants.