Study And Appraise On The Assay Method Of Cellulose And Hemicellulose In Roughage

It has been a puzzle for herbivore nutritionist that digestion and metabolism rat of cellulose and hemicellulose are only 30 to 60 percent even though rumen bacteria remain relatively homeostasis in herbivore anaimal.The effort to study how the roughage cellulose and hemicellulose influence digestion and metabolism rat will certainly facilitate to improve the roughage digestibility and develop the animal nutrition science.First,the Van Soest method for roughage determination was improved in this paper:i.e.the neutral detergent in NDF was replaced by the pH2.0 sulfuric acid detergent to get rid of pectin, and the acid detergent in ADF was replaced by the 2.0mol/L hydrochloric acid detergent to get rid of hemicellulose,making the assay easier and more accuracy.It was found that the measured value of cellulose and hemicellulose were generally low by this method than Van Soest method. The contant of hemicellulose was high than Van Soest method.And the contant of cellulose was low than Van Soest method.In this experiment,the cellulose and hemicellulose in roughage were divided into enzyme-hydrolysable(EH)and non-enzyme-hydrolysable(NEH)by enzyme methods.The assayed EH cellulose and EH semicellulose in corn stalk,wheat straw,rice straw and cotton stalk were 44.37%,43.04%,51.80%and 19.3%,and 60.23%,46.20%,47.60%and 66.35%respectively, which significance was not yet illustrated.The contant of the lignin and the ash were identical with Van Soest method.There are three forms of substances in the electron microscopy map of NDF.The forms are rabdoid,clew,and other irregularity shapes.There are two forms,namely rabdoid and clew in the electron microscopy map of treated samples with 2mol/l HCl and hemicellulase.And there is only one namely rabdoid in the electron microscopy map of treated ADF samples with cellulase. Moreover,there is only a form that is rabdoid in he electron microscopy map of NDF and ADF of animal's dung.From the forms,the irregularity shape is possiblly free state of hemicellulose that the former was hydrolyzed easily by enzyme.And the clew is possiblly free state of cellulose that the former was hydrolyzed easily by enzyme.And the rabdoid is combination of hemicellulose, cellulose and lignin named lignocellulose hard to hydrolyzed by enzyme.The assay method was verificated by three independent experiments of digestion and metabolism of sheep.ExperimentⅠStudy on the effects of magnetic-treated water on digestion and metabolism of sheep.Six 2-3-year-old non-pregnant Small Tail Han ewes,45.1±9.2 kg of average body weight, fed with diet composed of 66%of maize straw and 34%of concentrate,were received two treatments assigned with self-contrast experiment design.Animals in treatment 1(control)were given water and in treatment 2 MTW was supplied to study the effect of MTW on digestion and metabolism of sheep.The results showed that the digestibility of EH semicellulose and EH cellulose were 94.75～98.65%and 95.10～98.76%;the digestibility of NEH semicellulose and EH cellulose were 0～12.38%and 0～14.34%;the total digestibility of semicellulose and cellulose were 49.73～61.10%and 46.57～58.87%in diet.ExperimentⅡStudy on the effect of diets with different ratios of concentrate to with straw on digestion and metabolism of pregnant Small Tail Han ewe.eleven 2-3-year-old non-pregnant Small Tail Han ewes,48.70±5.87kg of average body weight.Sheep were divided into 3 groups, and were fed with 3 diets which ratios of concentrate to maize straw were 20:80,30:70 and 40:60 respectively,to study the effect of diet ratio of concentrate to roughage on STHS in the early period(50-65days)and the late period(110-125days)of pregnancy.The results showed that the digestibility of EH semicellulose and EH cellulose were 93.11～97.90%and 92.73～97.21%;the digestibility of NEH semicellulose and EH cellulose were 0～10.01%and 0～16.11%;the total digestibility of semicellulose and cellulose were 53..43～62.18%and 45.72～59.07%in diet.ExperimentⅢThe effect of drinking formalin on the digestion and metabolism of small tail Han sheep.Five 3-4-year-old non-pregnant Small Tail Han ewes,54.32±3.56 kg of average body weight,fed with same diet.Sheep were divided into two treatments assigned with self-contrast experiment design.The results showed that the digestibility of EH semicellulose and EH cellulose were 93.42～97.77%and 93.22～96.58%;the digestibility of NEH semicellulose and EH cellulose were 0～10.64%and 0～12.29%;the total digestibility of semicellulose and cellulose were 38.96～59.35%and 48.47～63.59%in diet.Bellows are major conclusions of this study: 1.Some roughage cellulose and hemicelluloses are enzyme-hydrolysable which give pretty stable and high digestibility,approximately 95%.Others of them are totally non-enzyme-hydrolysable and give very low even 0%digestion rat.This finding has significance in herbivore animal nutrition practice.2.The results of this study show that digestibility difference to cellulose and hemicelluloses among sheep individual is mainly due to their digestion ability to non- enzyme-hydrolysable parts of roughage.More complete degradation to non- enzyme-hydrolysable parts give high total digestion rat.So,critical nutritional study strategies should be put on metabolism of absorption and digestion to non- enzyme-hydrolysable cellulose in ruminate herbivore animal nutritional research.3.In three independent animal experiment,the first two different animal group can all gives the highest digestion rat to non- enzyme-hydrolysable cellulose and hemicelluloses.But in the last experiment,one animal display highest digestibility to both of non- enzyme-hydrolysable cellulose and hemicelluloses compare with other individual in same group.This results suggest that inheriting factor is not likely to play a important role in this process.A interesting result of this study is that sheep individual show coordinate digestibility to both of cellulose and hemicelluloses.It's significance remain to be elucidated in further study.