CHEMICAL COMPOSITION AND FERMENTATION CHARACTERISTICS OF MIXED MAIZE COB (Zea mays) AND SWEET POTATO VINE (Ipomoea batatas) SILAGE

Abstract

The study was conducted to assess the effect of dry matter levels on silage characteristics of maize cob and sweet potatoes vine mixtures. Maize cob (MC) and sweet potato vine (SPV) were chopped and mixed to provide dry matter levels of 70 %, 65 %, 60 % and 55 %, thus each level was considered as treatment T1, T2, T3 and T4, respectively. The materials were ensiled for 45 days in a ziploc polyethene bags and then placed in plastic containers. Each container carried one treatment with five replicates. There was significant (p <0.05) difference in dry matter (902.40±0.40 – 975.55±2.74 g/kg), crude protein (39.70±5.25 – 69.40±1.44 g/kg), neutral detergent fibre (525.55±1.07 – 661.70±30.48 g/kg), and hemicellulose (163.45±2.34 – 302.30±4.04 g/kg) across the treatments. A linear decrease (p <0.05) was observed in crude protein (CP) content, but dry matter (DM) and neutral detergent fibre (NDF) increased (p<0.05) across the treatments. Similarly, total volatile fatty acids (8.00±0.58 – 10.67±1.33 µmol/L) showed a numerical decrease (p>0.05) at lower DM levels. However, pH (4.22±0.13 – 4.73±0.06) increased (p<0.05) linearly across the treatments. It was concluded that low dry matter levels encourage formation of high quality silage. It was further deduced that microbial activities increased with a decrease in dry matter levels. Hence, for good quality silage using maize cob and sweet potato vine, 55 % DM level is recommended.