青贮时间对不同品种玉米青贮品质的影响

Effects of silage time on silage quality of different maize varieties

为探究内蒙古高原(东华北地区)玉米(Zea mays)青贮时间对青贮品质的影响,确定最适玉米青贮用品种及青贮时间,促进畜牧业发展。选用‘先锋38P05’、‘先玉1409’、‘海玉11’、‘利合228’和‘A6565’5个品种,设置青贮0、15、30、45、60和90 d,测定其青贮发酵品质及营养成分。结果表明,各品种青贮30 d后pH小于4.00;青贮过程中不同品种间乳酸(LA)、乙酸(AA)存在显著差异(P<0.05),丙酸(PA)、氨态氮/总氮(AN/TN)差异不显著(P>0.05),‘先玉1409’青贮45 d的LA最高占鲜物质(FM)的6.18%。各品种青贮45 d后营养成分变化趋于稳定;青贮90 d后‘先玉1409’的干物质(DM)、粗脂肪(EE)和相对饲喂价值(RFV)最高,干物质为21.73%,EE和RFV分别占干物质(DM)的5.43%、170.36%,粗蛋白(CP)损失率和酸性洗涤纤维(ADF)含量最低,CP损失率为36.63%,ADF占干物质的23.21%。综上,玉米青贮45 d后品质基本达到稳定状态,内蒙古高原(东华北地区)选用‘先玉1409’作为青贮原材料,青贮效果最佳。

To explore the effect of the silage time of maize(Zea mays)on silage quality in the Inner Mongolia Plateau(East and North China),we determined the most suitable maize varieties for silage and the optimal silage time to promote the development of animal husbandry.The fermentation quality and nutrient composition of‘Xianfeng 38P05’,‘Xianyu 1409’,‘Haiyu 11’,and‘Lihe 228’and‘A6565’were selected for assessment after 0,15,30,45,60,and 90 days of silage.The results showed that after 30 days,the pH of each variety was lower than 4.00.During silage,there were significant differences(P<0.05)in the lactic acid(LA)and acetic acid(AA)content between all varieties,but no significant differences(P>0.05)in propionic acid(PA)content and ammonium nitrogen/total nitrogen ratio(AN/TN).The highest LA content was 6.18 mg·g−1 fresh matter(FM)(‘Xianyu 1409’after 45 days of silage).Each index was stable after 45 days of silage.After 90 days of silage,‘Xianyu 1409’had the highest dry matter(DM),ether extract(EE),and relative feeding value(RFV),which were 21.73%DM,5.43%DM,and 170.36%DM,respectively.The CP loss rate and acid detergent fiber(ADF)content were 36.63%and 23.21%DM,respectively.In conclusion,the quality of maize silage reached a stable state after 45 days.‘Xianyu 1409’was selected as the raw material for silage in the Inner Mongolia Plateau(East and North China)as it showed the best silage effect.