Taro (Alocasia odora (C) Koch, Xanthosoma nigra (vell) Stellfeld and Colocasia esculenta  (L) schott)  in Central Vietnam: biomass yield, digestibility and nutritive value 

Du Thanh Hang, Nguyen Trung Kien  and T R Preston

Hue University of Agriculture and Forestry
Hue City, Vietnam
hangduthanh@yahoo.com.vn

Abstract

Four Taro varieties were investigated for biomass yield and nutritive value. Biomass yield was highest in Ao Trang (Colocasia esculenta) and Chia voi (Alocasia odora) from 26.3 to 26.7 kg per 10m² equivalent to 26.3 to 26.7 tonnes/ha, followed by Mon Tim (Alocasia odora) 23 tonnes/ha  and lowest in Mon Quang ((Xanthosoma nigra) 11 tonnes/ha. The chemical composition of Taro did not change with age but oxalate content had a trend to be less (from 4.1 to 2.6% in dry matter (DM)). DM contain in leaves was higher than in petioles (14.5 compared 6.6 %). Crude protein(CP) contain in leaves also higher than in petioles (22% compared 8% in DM).

Using three of ensiling of varieties which higher than biomass (Ao trang, Chia voi and Mon Tim) for intake trials. Results shown that the contribution of DM intake was higher than in Ao trang (50% total DM compared 42% in Chia Voi and Tim); CP intake from ensiled taro forages contributed 58% total CP in Ao Trang  compared 49% in Chia Voi and Mon Tim.

Final experiment in this study, comparation of digestibility and biological value (BV) between only basal diet (mixed of rice bran and maize) (BD) and bsal diet plus 50%  ensiled taro in DM (BDET) and BDET plus 5% rice wine by-product (BDETW) and BDET plus 0,2% DL-methionine (BDETM). The results shown that added 50% ensiled taro in basal diet (BD) increasing biological value (BV) from 52 to 73%; Added 5% rice wine-by-product in ensiled diet (BDETW) improved BV from 73 to 81%. And added methionine in diet (BDETM) is not effect on digestibility and N retention in growing pigs.

Key word: Taro, Biomass yield, pig, intake, digestibility, biological value, rice wine-by-product, methionine.