Effect of steam explosion of crop residues on chemical compositions and effi cient energy values

3^rd International Conference on Veterinary & Livestock

November 02-03, 2017 Bangkok, Thailand

Xin Wu, Yongfeng Zhao and Qingxiang Meng

China Agricultural University, China

Posters & Accepted Abstracts: J Vet Sci Technol

Abstract :

In China, less than 15% crop residues were used as feedstuff because of its poor palatability and low digestibility. Steam explosion is a physical and chemical feed processing technology which has great potential to improve sapidity and digestibility of crop residues. To investigate the eff ect of steam explosion on chemical compositions and effi cient energy values, crop residues (rice straw, wheat straw and maize stover) were processed by steam explosion (steam temperature 120-230 �?°C, steam pressure 2-26 kg/cm2, 40 min). Steam-exploded crop residues were regarded as treatment groups and untreated ones as control groups, nutritive compositions were analyzed and eff ective energy values were calculated by prediction model in INRA (1988, 2010) for both groups. Results indicated that the interaction between treatment and variety has signifi cant eff ect on chemical compositions of crop residues. Steam explosion treatment of crop residues decreased neutral detergent fi ber (NDF) signifi cantly (P<0.01) and compared with untreated material, NDF content of rice straw, wheat straw and maize stover lowered 21.46%, 32.11%, 28.34%, respectively. Acid detergent lignin (ADL) of crop residues increased signifi cantly aft er steam explosion (P<0.05). Th e content of crude protein (CP), ether extract (EE) and ash increased signifi cantly aft er steam explosion (P<0.05). Moreover, predicted eff ective energy values of each steam-exploded residue were higher than that of untreated ones. Th e digestible energy (DE), metabolizable energy (ME), net energy for maintenance (NEm) and net energy for gain (NEg) of steam-exploded rice straw were 3.06, 2.48, 1.48 and 0.29 MJ/kg, respectively and increased 46.21%, 46.25%, 49.56% and 110.92% compared with untreated ones (P<0.05). Correspondingly, the energy values of steam-exploded wheat straw were 2.18, 1.76, 1.03 and 0.15 MJ/kg, which were 261.78%, 261.29%, 274.59% and 1014.69% greater than that of wheat straw (P<0.05). Th e above predicted energy values of steam exploded maize stover were 5.28, 4.30, 2.67 and 0.82 MJ/kg and raised 109.58%, 107.71%, 122.57% and 332.64% compared with the raw material (P<0.05). In conclusion, steam explosion treatment could signifi cantly alter the cell wall and the other components of crop residues. Th ere existed strong interaction between steam explosion treatment and species of crop straw. Th e eff ect of steam explosion was much more obvious for wheat straw than the other two kinds of residues under the same condition.