Chittavong Malavanh et al., 2008. Livest. Res. Rural Dev., 20 (Supplement)

An experiment was carried out at laboratory scale to determine the optimum level of molasses for ensiling taro (Colocasia esculenta (L.) Shott) leaves. The leaves were collected from Nongveng village, near Vientiane City in Laos, and were chopped into small pieces (2 to 3 cm) and ensiled in plastic bags (capacity 2 kg) with levels of sugarcane molasses of 0, 2, 4 and 6% (dry matter [DM] basis). The mean total sugar content (°Brix) of the molasses was 77. Each molasses level was repeated five times, corresponding to ensiling periods of 0, 7, 14, 21 and 28 days. At each ensiling date samples were taken for determination of pH, DM, ammonia nitrogen (NH3-N), water extractable DM and N, and total N. Physical characteristics, such as smell and colour, were observed and recorded. After 7 days the colour for all treatments had changed from green to yellow-brown and was darker at higher levels of molasses. Each treatment had an acceptable smell. The pH values for all treatments were around 6 at day 0 and then quickly fell below 5, the value being dependent on ensiling time and the level of molasses (P<0.05). At day 0 the concentration of NH3-N was very low on all treatments, but from 7 days onwards the concentration had increased with the time of ensiling on all treatments; the highest value was 5,900 mg/kg DM on the 0% level of molasses at 28 days. The ammonia-N concentration decreased as the level of molasses increased. Ensiling for 28 days with 4% molasses reduced oxalate concentration from 2.20 to 0.37% of DM. A level of 4% molasses and an ensiling period of between 14 and 21 days appeared to be the most appropriate procedures for ensiling Taro leaves as determined by pH, ammonia concentration and water extractable DM and N.