瞬时弹射式蒸汽爆破对玉米秸秆微贮营养成分和牛瘤胃营养物质消失率的影响

Effect of ICSE on nutritional components of corn stover and rumen reduction rate in cow rumen

关键词:  微贮  弹射式蒸汽爆破  玉米秸秆  瘤胃消化率

Key words:  silage  ICSE  corn stover  rumen digestibility

摘要:

为研究干黄玉米秸秆经瞬时弹射式蒸汽爆破(ICSE)预处理后微贮产品营养成分及奶牛瘤胃营养物质消失率的变化规律，使用气压2.0 MPa保持150 s、气压1.8 MPa保持 200 s和气压1.2 MPa 保持200 s 3组预处理条件，每组4个重复，用ICSE技术对玉米秸秆进行预处理，并接种乳酸菌在厌氧条件下微贮60 d；微贮后的秸秆产品进行氨基酸成分分析、主要营养成分测定和真菌毒素含量检测；采用尼龙袋法测定并评价微贮秸秆产品的奶牛瘤胃干物质消失率。结果表明:1.8 MPa 200 s预处理后微贮饲料的品质最佳，其中粗蛋白质含量10.85%，是2.0 MPa 150 s预处理组(5.99%)近两倍(P<0.05)，高于对照组(8.38%)和1.2 MPa 200 s预处理组(10.46%)；1.8 MPa 200 s预处理组的奶牛瘤胃干物质消失率也最高，达到77.36%，极显著高于对照组和1.2 MPa 200 s预处理组(P<0.01)，显著高于2.0 MPa 150 s预处理组(P<0.05)。综上，瞬时弹射式蒸汽爆破预处理结合乳酸菌微贮后的干黄玉米秸秆品质较好，在反刍动物养殖中具有一定应用价值。

Abstract:

The purpose of this study was to investigate the changes of nutrient components and material digestion rate of the dried corn stalks in the dairy cows rumen after instant catapult steam explosion(ICSE)pretreatment. ICSE pretreatment of dried corn stalks was carried out under conditions of 2. 0 MPa 150 s, 1. 8 MPa 200 s, and 1. 2 MPa 200 s, with 4 repetitions in each group. Corn stalks were pretreated by ICSE, inoculated with Lactobacillus, and then stored under anaerobic conditions for 60 days. After that, amino acid composition, main nutrient components, and mycotoxin content of the corn silage were analyzed. The nylon bag method was used to evaluate the dry matter(DM)reduction rate in dairy cow rumen. The results showed that quality of the corn silage was excellent in the condition of 1. 8 MPa 200 s pretreatment containing 10. 85% crude protein, which was significantly(P<0. 05)two-folds higher than that in the 2. 0 MPa 150 s pretreatment group(5. 99%). Further, the crude protein of 1. 8 MPa 200 s pretreatment group was higher than that in control(8. 38%)and 1. 2 MPa 200 s pretreatment(10. 46%)groups. Further, 1. 8 MPa 200 s pretreatment group exhibited the superior DM degradation rate(77. 36%), which was extremely significantly(P<0. 01)higher than that of control and 1. 2 MPa 200 s pretreatment, while it also presented significantly(P<0. 05)higher DM degradation rate than 2. 0 MPa 150 s pretreatment group. Therefore, the dried corn stover product has preferable quality by combining ICSE pretreatment and silage associated with lactic acid bacteria, which will have a promising application value in ruminant breeding area.