| The utilization rate of stalks is poor though stalks have been treated for one hundred years. The present trials were aimed at the effects of maize stalk treated rapidly by compound-alkali and combination of urea and lime in vitro, in sacco and in vivo, respectively.Three experiments in vitro were to choose the treatment condition of lime(the level of lime, moisture and reaction period ) , compound-alkali (different levels of sodium hydroxide or urea were added to 40g lime kg"1 DM stalk)and combination treatment of urea and lime(reaction period). Four different rations were fed to four individually housed rumen-cannulated Northeast hemi-fine-fleece sheep in a 4X4 Latin square experiment, the design was to study influences of stalk treated by compound-alkali and combination of urea and lime on rumen digestion and rumen metabolism . A feeding trial of 16 Texel X Northeast hemi-fine-fleece sheep cross-bred ram was conducted to study effects of the treated rations on the growth and metabolism of lamb.Results showed thai :1 The moisture treatments of 40%, 50% and 60% had no significant difference in the concentration of NDF,ADF and DMD48, and the reaction time between one week and two weeks had no significant difference yet. The effects were significant with the increasing level of Lime. It is limited that the level of Calcium in lamb ration, so 40g lime kg' DM stalk was chosen.2 The compound treatment was more effective than lime. The compound treatment of lime and sodium hydroxide was more effective than the treatment of Lime and urea. The treatment of 40g lime and 20g sodium hydroxide kg"1 stalk DM with 40% moisture for one week was optimized. High pH value, 40g lime and 20g urea kg"1 DM stalk couldn't inhibit the mould in maize stalk, the following experiment showed that the treatment of compound- alkali for three days was optimized.3 Rate of hydrolysis of urea was accelerated by adding excessive lime, the reaction period of combination urea and lime treatment was only 14days, and 16 days was shorted compared with traditional urea treatment at 20?7癈 (ambient temperature). The reaction period of combination urea and lime treatment was only 27days and 33 days was shorted compared with traditional urea treatment at 11 ?4 癈 (ambienttemperature).4 The stalk treated by compound-alkali and combination of urea and lime could improve the disappearance of DM, OM, NDF, ADF incubated 48 hours in rumen-cannulated sheep, the improvement of disappearance of DM, OM, NDF, ADF as control was 45.54%, 45.03%; 42.02%, 44.64%; 5056%, 49.09%; 36.81%, 40.14% , respectively.5 The total mixed rations based on maize stalk treated by compound-alkali and combination of urea and lime had no influence on pH value and concentrations of NH3 -N and total nitrogen in rumen liquor.6 The treated rations by compound-alkali and combination of urea and lime could improve voluntary intake as control by 22.36%, 22.50%; enhance average daily gain by 58.04%, 58.84%; decrease voluntary intake/average daih gain by22.55%, 22.89%, respectively.7 The treated rations by compound-alkali and combination of urea and lime could increase effectively apparent digestibility of DM, OM, CP, NDF, ADF as control by 12.50%, 11.20%; 8.42%, 8.21%; 4.98%, 16.07%; 19.18%, 22.06%; 18.32%, 18.31%, respectively.8 The treatments had no effect on nitrogen balance and the rate of nitrogen deposit, but combination urea and lime treatment had a higher nitrogen balance and the rate of nitrogen deposit.Master Candidate: He Yonghui Supervisor: Prof. Li Jie Major: Animal Nutrition and Feed Science...
|
PDF Full Text Request