体外法评价玉米秸秆、小麦秸秆与玉米秸秆青贮的组合效应

Associative Effects of Cornstalk,Wheat Straw and Corn Stalk Silage by Gas Production Technique in Vitro

试验旨在利用体外产气法研究玉米秸秆(CS)、小麦秸秆(WS)与玉米秸秆青贮(CSS)的组合效应。试验采用单因素试验设计,首先研究CS与WS,筛选出的最优CS-WS组合后,再与CSS选出最优组合,每个组合设3个重复。结果表明:不同饲料组合间产气量达显著(P<0.05)或极显著(P<0.01)差异,CS与WS组合的SFAEI在60∶40比例时达到最优、最优CS-WS组合与CSS组合在40∶60产气量达到最优;各饲料间的干物质消失率影响达显著(P<0.05)或极显著(P<0.01)水平,其最优SFAEI的比例组合分别是50∶50和20∶80;不同饲料组合间pH差异不显著(P>0.05);微生物蛋白产量在两组饲料组合中达极显著(P<0.01)影响,分别是随小麦秸秆比例的增加而减少、随玉米秸秆青贮比例的增加而增加,其最优SFAEI的比例组合分别是60∶40和40∶60;不同饲料组合间氨态氮浓度影响显著(P<0.05),在10.71~26.05mg/dl变化,均在正常浓度范围内;用多项组合效应指数评定各饲料组合的最优比例分别为:CS和WS为60∶40;最优CS-WS组合(60∶40)与CSS为20∶80。综合分析得出:玉米秸秆、小麦秸秆和玉米秸秆青贮三者的适宜组合比例为12∶8∶80。

This research was to investigate the associative effects of cornstalk （CS）, wheat straw （WS）, and corn stalk silage （CSS） by gas production technique in vitro. Single factor experiment was de- signed to begin with CS and WS to screen for the best combination of CS-WS, followed by a second screen for the best combination of CS-WS-CSS with the best combination of CS-WS and CSS. All combinations a- bove were tested with the ratios of 100 ： 0, 80 ： 20, 60 ： 40, 50 ： 50, 40 ： 60, 20 ： 80 and 0 ： 100, with 3 replicates. Gas production （GP）, rate of dry matter loss, pH, microbial crude protein （MCP）, ammonia nitrogen （NH3-N）, as well as their single factor associative effects index （SFAEI） and multiply factors as- sociative effects index （MFAEI） were evaluated. The results are shown as follows： Different combinations showed significant differences （P〈0.05 or P〈0.01） on the rate of gas production. To produce the best SFAEI of gas rate, the optimal ratio for CS and WS was 60 ： 40, and the best combination of CS-WS and CSS was 40：60; Significant differences （P〈0.05 or P〈0.01） were detected for dry matter loss rate be- tween different combinations, and the best SFAEI of dry matter loss was the combination of 50：50 and 20：80, respectively. There was no significant difference on pH between different feed combinations （P〈 0.05）. MCP yield was extremely significantly （P〈0.01） different between the two feed combinations. To be specific, MCP decreased when increasing WS proportion, while increased when CSS proportion increased, and the best SFAEI of MCP was the combination of 60 - 40 and 40 ： 60, respectively. NH3-N concentration was significantly different （P〈0.05） between different feed combinations, changing from 10.71 to 26.05 mg/dl, but they were within the normal range. Using MFAEI to assess the optimal ratios of associative effects, CS and WS were 60 ： 40, the best combination of CS-WS （60 ： 40） and CSS were 20 ： 80. Overall, the best combination of CS-WS-CSS was 12 ： 8 ： 80.