利用体外产气法对不同处理秸秆-薯渣混合料营养价值的评价研究

摘要

本试验旨在通过体外产气法评定不同处理水稻秸秆-马铃薯淀粉渣混合料（PSF：秸秆-薯渣混合料、SSF：秸秆-薯渣固态发酵产物、SFS：秸秆-薯渣青贮）的营养价值。混合料通过体外发酵试验，测定不同时间点的累积产气量，以及24 h体外发酵参数和养分降解率，并分析其发酵动力学参数与养分之间的相关性。结果表明：SFS除72 h，其余时间点的累积产气量均显著高于PSF和SSF（P＜0.05），SFS和SSF理论最大产气量显著高于PSF（P ＜0.05），分别提高67.2%和71.6%，但PSF产气速度、产气延滞期显著高于SSF和SFS（P＜0.05）。相比PSF，SSF和SFS显著提高体外干物质降解率（IVDMD）、体外中性洗涤纤维降解率（IVNDFD）和体外粗蛋白质降解率（IVCPD）（P＜0.05），分别提高34.5%和5.1%、41.8%和5.9%、57.8%和50.0%。饲料最大产气量与酸性洗涤纤维（ADF）含量呈显著正相关关系（P ＜0.05），产气速度与ADF呈显著负相关关系（P ＜0.05），产气延滞期与ADF之间呈极显著负相关关系（P ＜0.01），饲料发酵参数与粗蛋白质（CP）、粗灰分（Ash）、中性洗涤纤维（NDF）无相关性（P＞0.05）。结合产气量与体外降解数据可知，SSF和SFS饲用价值较高，为秸秆-薯渣混合料作为饲料原料合理配制反刍动物日粮提供理论指导。%The objective of this study was to evaluate the nutritional value of straw-pulp at different treatments using in vitro gas production.The treatments were PSF,SSF and SFS.The PSF was the combination of the rice straw and the potato pulp with no additive.The SSF was the solid-state fermentation of the rice straw and the potato pulp.The SFS was the silage of the rice straw and the potato pulp.The volume of gas production in different time ,fermentation parameters and nutrient degradation rate of the three different feeds(PSF,SSF,SFS)at 24 h by in vitro were measured.Otherwise,the rela-tionships between fermentation kinetics and nutrient composition were analyzed.The results showed that the volume of gas production of the SFS,was significantly increased except at 72 h compared with PSF and SSF (P < 0.05).The theoretical gas production of the SFS and SSF were significantly increased compare with the PSF (P < 0.05),the value were 67.2%and 71.6%.But the rate of gas production and the demurrage time of the gas production in PSF were both higher than the other two groups(P < 0.05).The IVDMD,IVNDFD and IVCPD of the SSF and SFS were higher than the PSF(P < 0.05). Comparing to PSF the IVDMD in the two groups were increased by 34.5% and 5.1%,the IVNDFD were increased by 41.8%and 5.9%;the IVCPD were increased by 57.8%and 50.0%.Correlation analyses indicated that the theoretical maxi-mum gas production was significant positively related to ADF (P < 0.05),the rate of gas production was significant nega-tively related to ADF(P<0.05),and the demurrage time of the gas production was extremely significant negatively related to ADF(P < 0.01).But the gas production kinetic parameters were no significant related to CP,Ash and NDF(P > 0.05). Considering to the gas production and the degrade rate,the SSF and SFS have the high nutrition value as forage,which could supply scientific basis for diet formulation in dairy practice.