【作者】 郭雪峰；

【导师】 卢德勋； 金海；

【作者基本信息】 内蒙古农业大学 ， 动物营养与饲料科学， 2008， 博士

【摘要】 本论文分三部分:第一部分根据常规方法和CNCPS体系测定牧草各项营养指标建立内蒙古白绒山羊体外甲烷产生量的估测模型;第二部分利用SF₆示踪技术实测常规牧草的体内甲烷产生量,验证由体外法建立模型的可靠性;第三部分测定不同放牧期内蒙古白绒山羊的甲烷产生量,并研究瘤胃内环境指标、牧草营养成分和消化率的动态变化、甲烷菌多态性和总甲烷菌的相对量研究对甲烷产生的影响,探讨放牧绒山羊瘤胃甲烷产生的影响因素。第一部分内蒙古白绒山羊甲烷产生量模型的建立。通过测定内蒙古荒漠化草原上内蒙古白绒山羊经常采食的4科31种牧草常规营养成分,并按照康乃尔净蛋白碳水化合物体系（CNCPS）的指标对饲料营养素进行进一步划分,同时利用体外培养技术（IVGPT）在体外培养条件下测定每种牧草的甲烷产生量,建立由饲草营养指标估测内蒙古白绒山羊甲烷产生量的数学模型。IVGPT技术与常规饲料营养成分指标及CNCPS划分指标的相关性分析得知:甲烷产生量与蛋白质部分、体外干物质降解率及消化率呈正相关性关系,而与碳水化合物除CB2外均呈负相关关系。通过牧草常规营养成分建立体外法估测甲烷产生量的模型分别为:豆科: Y=-3.108-1.594CP+0.855NDF-1.193ADF-0.102IVDMR+1.266IVDMD （ n=7 ,R²=0.999）藜科:Y=69.544-1.059CP-0.473NDF+0.618ADF+0.812ADL- 1.333NFE+0.349IVDMD（n=10,R²=0.940）菊科:Y=100.117+0.687CP-1.139ADF-0.224IVDMR- 0.575IVDMD（n=6,R²=0.995）禾本科:Y=199.864+1.140CP-3.172NDF+1.417ADF-1.725ADL -0.845IVDMR+0.178IVDMD（n=8,R²=0.984）通过CNCPS建立体外法估测甲烷产生量的模型分别为:豆科:Y=88.501-3.234CA+0.577CB1-1.731CC+6.249PB1 +40.381PB3-43.412PC（n=7,R²=0.999）藜科:Y=54.5924+0.828CB1-0.193CC-2.130PA-0.565PB1+16.082PB3 -15.717PC-0.161CHO-0.431NFC（n=10,R²=0.986）菊科:Y=38.783+0.130CB1-0.124CB2-0.529CC+1.051PB3-1.714PC（n=6,R²=0.999）禾本科:Y=-410.282+0.530CA+3.613CB2+19.284CC-161.365PA +54.942PB1-89.731PB3+45.747PC（n=8,R²=0.999）第二部分对体外法建立甲烷产生量估测模型的验证。试验以4只健康体重相近（29±1kg）、年龄相同的内蒙古白绒山羊成年羯羊为实验动物,通过SF₆示踪法实测6种日粮在体内的甲烷产生量。6种试验日粮是:D1（干苜蓿）,D2（玉米青贮）,D3（玉米秸秆）,D4（冰草）、D5（沙打旺）,D6（M）（维持水平:20%苜蓿+80%羊草）,并比较了在采食D6日粮条件下限饲（维持水平）与自由采食（L）两种饲喂制度下的甲烷产生量;同时通过IVGPT技术测定上述日粮在体外培养条件下的甲烷产生量。结果显示:日粮D1、D2、D3、D4、D5、D6（M）和D6（L）的体内甲烷产生量分别为21.02、19.39、20.26、20.37、17.99、18.06和17.71g/kgDMI;相应的体外甲烷产生量分别为:20.62、17.23、19.01、19.74、17.01、17.12和16.44g/kgDM,体内外甲烷产生量差异不显著,其相关系数为0.941（P=0.002）。第三部分不同放牧期内蒙古白绒山羊瘤胃甲烷产生量的测定及其影响因素的研究。1本研究选用6只体重相近、体况良好的内蒙古白绒山羊,试验地点为内蒙古乌拉特中旗巴音哈太种羊场,利用链烷烃技术测定不同放牧期内蒙古白绒山羊采食量及采食牧草植物学组成。结果表明:内蒙古白绒山羊不同放牧期的采食量分别为:幼嫩期0.779 kg/d、旺盛期0.845 kg/d和枯黄期1.632kg/d,采食牧草植物学组成分别为:幼嫩期为寸苔草13.42%、小白蒿6.43%、短花针茅71.85%、彭氏鸢尾3.93%和骆驼蓬4.35%;旺盛期为蒺藜7.9%、骆驼蓬42.28%、牤牛儿苗8.78%、沙葱12.1%、狗尾草8.56%和早熟禾20.4%;枯黄期为黄蒿68.9%、黄花蒿13.3%和寸苔草17.82%;2本研究利用IVGPT结合不同放牧期内蒙古白绒山羊的采食量及采食牧草植物学组成结果测定不同放牧期内蒙古白绒山羊的甲烷产生量。结果表明:不同放牧期甲烷产生量分别为:幼嫩期16.76g/d、旺盛期19.02g/d和枯黄期33.92g/d。3本研究对不同放牧期内蒙古白绒山羊采食牧草的营养成分动态变化,及牧草营养成分消化率的动态变化与甲烷产生量的相关性进行了分析。结果表明:不同放牧期牧草中的蛋白含量与内蒙古白绒山羊的每千克干物质所产生的甲烷产生量成正相关关系,而与ADF和NDF的含量呈负相关关系;不同放牧期内蒙古白绒山羊每天甲烷产生量与牧草中NDF和ADF的消化率与甲烷产生量呈正相关性关系,与CP和OM的消化率呈负相关关系。4本研究对舍饲条件下与不同放牧期内蒙古白绒山羊瘤胃内环境指标的动态变化,包括氨氮（NH3-N）、pH值、挥发性脂肪酸（VFA）的动态变化与甲烷产生量的相关性进行了分析。结果表明:不同放牧期及舍饲条件下瘤胃内pH值的动态变化没有显著性变化;不同放牧期及舍饲条件下瘤胃内NH3-N浓度与牧草中CP的含量呈正相关关系,与每千克干物质所产生的甲烷呈正相关关系;不同放牧期及舍饲条件下瘤胃内乙丙酸比例枯黄期极显著高于幼嫩期和旺盛期,显著高于舍饲条件（P﹤0.05）,与每天的甲烷产生量呈正相关关系。5本研究通过MCRa基因技术研究了不同放牧期内蒙古白绒山羊瘤胃内甲烷菌多态性。结果显示:不同放牧期内蒙古白绒山羊瘤胃内至少存在6个不同的基因类型,测序结果表明上述基因型均属于未培养系列,但部分基因类型达到97%的同源性,不同放牧期瘤胃内甲烷菌多态性无显著性差异（P﹥0.05）。6本研究利用荧光染料结合Real Time PCR技术测定了不同放牧期及舍饲条件下晨饲前2h、0h和晨饲后2h的总甲烷菌数对甲烷产生量的影响。结果表明:舍饲条件下晨饲后2h的甲烷菌数最高;舍饲及放牧条件下瘤胃内总甲烷菌数为舍饲条件﹥牧草生长幼嫩期﹥旺盛期﹥枯草期,3个时间点得甲烷菌总数与甲烷产生量无显著性相关性。更多还原

【Abstract】 The papers divided into three parts. Part one was to establish methane production models for pastures grazed by Inner Mongolian Cashmere goats by use of nutritional values of pastures based on routine analysis and CNCPS. Part two was to determine methane production of Inner Mongolian Cashmere goats by Sulfur Hexafluoride （SF₆）tracer technique in order to validate above established models. Part three was to determine the methane production of Inner Mongolian Cashmere goats in different pastures growing periods and to study the influencing factors on methane production at different pastures growing periods,such as pH value rumen and other fermentation parameters in the rumen, nutritional composition and digestibility of pastures, phylogenic and population of methanogensPART I Established prediction models of methane production for pastures grazed by Inner Mongolian Cashmere goats.Nutritional composition of 31 species in 4 families growed in desert grassland were analyzed based on CNCPS and routine analysis, meanwhile methane production of the pastures was determined by in vitro gas production technique（IVGPT）. The results showed that positive correlations were found between the methane production and CP content, IVDMD, IVDMR, but negative correlation between methane production and CHO of the pastures except CB2.The prediction models of the pastures methane production based on nutritional composition were as follows: Leguminous pastures: Y=-3.108-1.594CP+0.855NDF-1.193ADF-0.102IVDMR+1.266IVDMD（R²=0.999,n=7） Chico pastures: Y=69.544-1.059CP-0.473NDF+0.618ADF+0.812ADL-1.333NFE+ 0.349IVDMD（R²=0.940,n=10） Composite pastures: Y=100.117+0.687CP-1.139ADF-0.224IVDMR-0.575IVDMD（R²=0.995,n=6） Germanous pastures: Y=199.864+1.140CP-3.172NDF+1.417ADF-1.725ADL-0.845IVDMR+ 0.178IVDMD（R²=0.984,n=8） Prediction models of methane production based on CNCPS were as follows: Leguminous pastures: Y=88.501-3.234CA+0.577CB1-1.731CC+6.249PB1+40.381PB3-43.412PC（R²=0.999,n=7） Chico pastures: Y=54.5924+0.828CB1-0.193CC-2.130PA-0.565PB1+16.082PB3-15.717PC- 0.161CHO-0.431NFC（R²=0.986,n=10） Composite pastures: Y=38.783+0.130CB1-0.124CB2-0.529CC+1.051PB3-1.714PC （R²=0.999,n=6） Germanous pastures: Y=-410.282+0.530CA+3.613CB2+19.284CC-161.365PA+54.942PB1 -89.731PB3+45.747PC（R²=0.999,n=8）Part 2 Validation of the methane production prediction models. Four Cashmere goats, aged 1.5±0.21years and BW of 30±1.2 kg were used for measuring methane production for 6 diets by SF₆ tracer technique. The diets were Alfalfa dry （D1）, Erect Milkvetch （D2）, Wheatgrass （D3）, Corn silage （D4）, Corn straw （D5） and restricted feeding: 20%Alfalfa+80%Chinese Wildrye （D6）, the methane production of the goats fed D6（M）at restricted feeding and D6（L）ad labium feeding was compared. The results showed that methane production determined by IVGPT were 20.62、17.23、19.01、19.74、17.01、17.12 and 16.44g/kgDM for D1,D2,D3,D4,D5,D6（M） and D6（L）,the corresponding values by SF₆ trace technique were 21.02、19.39、20.26、20.37、17.99、18.06 and 17.71g/kgDM.There was significant correlation between the values measured by IVGPT and SF₆ techique,and the coefficient correlation was 0.941（P=0.002）.Part 3 Study on determination of methane production of grazing Inner Mongolian Cashmere goats in different patures growing periods and influencing factors on methane production of grazing Inner Mongolian Cashmere Goats1 Dry matter intake, pasture botanical composition of grazing Inner Mongolian Cashmere goats were measured in different pastures growing periods （young, prosperity and dry period） using Alkane technique. Six Inner Mongolia Cashmere goats, aged 1.5±0.21years and BW of 25±1.2 kg were selected from BAYINHATAI Cashmere goats Breeding farm,in WULATEzhongqi, Inner Mongolian. The results showed that dry matter intake（DMI） at different pastures growing periods were 0.779、0.845 and 1.632kg/d respectively. Pasture botanical composition were Carex duriusula 13.42%、Artemisia frigida Willd 6.43%、Stipa breviflora 71.85%、Iris bungei maxim 3.93% and Peganum harmala L4.35% in young pasture period and Puncturevine Caltrop Fruit 7.9%、Peganum harmala L 42.28% Erodium stephanianum Willd 8.78%、Allium victorialis L 12.1%、Green Bristlegrass Herb 8.56% and Poa alpigena 20.4% in prosperity pasture period, Sweet Wormwood Herb 68.9%、Artemisia annua L 13.3% and Carex duriusula 17.82% in dry pasture period.2 Methane production of the grazing Inner Mongolia Cashmere goats at different pasture growing periods was measured by IVGPT. The methane production of the different pasture growing periods were 16.76g/d（young pasture period）、19.02g/d（prosperity pasture period） and 33.92g/d（dry pasture period）.3 Correlation analysis of dynamic changes of nutritional composition and digestibility of pastures and the methane production and influencing factors on the methane production in different pastures growing periods were studied by dynamic changes of nutritional composition and digestibility of the pastures grazed by Inner Mongolian Cashmere goats. The results showed that a positive correlation between the methane production per kg DMI and CP content of pastures was found, but there was a negative correlation with ADF and NDF content. However positive correlation was also found between the methane production （g/d） of Inner Mongolian Cashmere goats and ADF and NDF digestibility of pastures and there was negative correlation with CP and OM digestibility.4 Correlation analysis of rumen environment values and the methane production and influencing factors on the methane production in different pastures growing periods were studied by dynamic changes of fluids pH and other fermentation parameters in the rumen of Inner Mongolian Cashmere goats, including NH3-N content, pH value and volatility fatty acid （VFA）.The results showed dynamic changes of pH values in the rumen had no significant between difference pastures growing periods and feedlot feeding periods, and had no significant impact on methane emission; the concentration of NH3-N in the rumen and CP content of pasture had a positive correlation with the methane production expressed as per kg DMI both in feedlot condition periods and grazing periods. The A/P ratio in the rumen in dry pasture period was significantly higher than that in young and prosperity pasture period, and the two values were higher than that in feedlot feeding periods, There was a positive relationship between A/P ratio and the methane production expressed as g/d both in different pastures growing periods and feedlot feeding periods.5 The methanogens phylogenic of Inner Mongolian Cashmere goats at different pastures growing periods was studied by MCRa gene method, and analysis of correlation with the methane production was made. The results showed that: In the rumen of Inner Mongolia Cashmere goats, there were at least 6 different gene styles at different pastures growing periods, sequencing analysis results showed the gene styles all belonged to uncultured styles, but there was 97% homology at some of different gene styles. There was no significant difference on methanogens species in the rumen at different pastures growing periods.6 The total methanogenes population was quantitated through fluor dye combined with Real Time PCR method at 2h before morning feeding and 0h、2h after morning feeding at different pastures growing periods and feedlot feeding periods .The results showed that at 2h after morning feeding in feedlot feeding periods, the population of methanogens was the the highest; the order of total methanogens population of three times was feedlot feeding periods﹥young pasture period﹥prosperity pasture period﹥dry pasture period; and the methanogens population had no significant coefficient correlation between the methane production and values.更多还原