体外产气法评价不同青贮添加剂处理下汽爆玉米秸秆品质

Quality evaluation on steam-exploded corn strawfermented with different additives by invitro gas production

摘要:

为评价不同青贮添加剂处理对汽爆玉米秸秆饲用价值的影响,采用体外产气法并结合扫描电镜,对比添加剂Sila-max(MAX)、Sila-mix(MIX)、纤维活性菌(活性菌)以及空白(CK)处理的汽爆玉米秸秆微观结构、体外消化率及瘤胃发酵特性。结果表明:添加剂组体外48 h累积产气量显著高于CK组(P＜0.05);MAX组体外干物质消化率(DMD)、中性洗涤纤维消化率(NDFD)最高,分别达51.59%、31.06%,MIX组体外酸性洗涤纤维消化率(ADFD)最高,达31.50%,不同处理间均无显著差异(P＞0.05);MAX组体外挥发性脂肪酸(TVFA)含量最高,与其他处理组差异显著(P＜0.05);不同处理下NH3-N浓度、pH均在瘤胃适宜的范围内;MIX组微生物蛋白(MCP)含量最高,与MAX组无显著差异(P＞0.05),二者与其他处理组差异显著(P＜0.05);通过扫描电镜观察,加入添加剂对秸秆纤维结构有明显破坏作用。综上,不同添加剂对汽爆玉米秸秆的作用不同,其中MAX处理的汽爆玉米秸秆产气效果较好,可推广使用。

Abstract:

This study aimed to evaluate the effects of different additives on the feeding value of steam-exploded corn straw.The microstructure,in vitro digestibility and rumen fermentation characteristics of steam-exploded corn straw,treated with different additives including Sila-max(MAX),Sila-mix(MIX) and Fiber active bacteria(Active bacteria) together with without any additives as the blank(CK),were analyzed using SEM and in vitro gas production method.The results showed that the cumulative gas production at 48 hours in all additive treatments were significantly greater than in CK(P＜0.05).DMD and NDFD in MAX group were the greatest,reaching 51.59% and 31.06% respectively.ADFD in MIX group was 31.50%,but did not differ between CK and other group.TVFA in MAX group were significantly higher than that in the other groups(P＜0.05).NH3-N and pH were in normal range of rumen for all treatments.MCP content in MIX group was the greatest and did not differ significantly from that in MAX group,while significantly differed from that in the other treatments(P＜0.05).SEM results showed that additives could obviously damage the structure of straw fiber.In conclusion,different additives had different effects on steam exploded corn straw.Sila-max(MAX) treatment had better gas production and fermentation parameters,which could be used widely in silage practice.