淋雨和添加剂对苜蓿青贮品质的影响

Effect of Rain and Additives on Quality of Medicago sativa Silage

为研究淋雨和添加剂对苜蓿(Medicago sativa)青贮品质的影响,试验设新鲜和淋雨苜蓿青贮2个因素,添加剂分别为对照、甲酸、绿汁发酵液、改良绿汁发酵液、玉米粉、绿汁发酵液+玉米粉、改良绿汁发酵液+玉米粉7个水平,共14个处理。青贮90d后,测定各处理的pH、氨态氮、有机酸、营养成分和硝基化合物含量。结果表明:淋雨和添加剂均极显著降低苜蓿青贮饲料pH、氨态氮、乳酸和乙酸含量(P<0.01)。改良绿汁发酵液+玉米粉组的乳酸含量显著高于对照和其他处理组(P<0.05)。淋雨和添加剂显著影响苜蓿青贮饲料的干物质、酸性洗涤纤维、中性洗涤纤维含量和缓冲能值(P<0.05),添加剂对粗灰分、粗蛋白、粗脂肪和水溶性碳水化合物含量有显著影响(P<0.05)。淋雨、添加剂及其交互作用极显著影响苜蓿青贮饲料的硝酸盐和亚硝酸盐含量(P<0.01)。添加剂可改善淋雨苜蓿青贮的发酵品质,其中改良绿汁发酵液+玉米粉组合效果最明显。

The effect of rain and additives on the quality of Medicago sativa silage for fresh and rained alfalfa silage are reported.Additive treatments include control group（CK）,formic acid（FA）,previous fermented juice（PFJ）,improved previous fermented juice（IPFJ）,corn flour（CF）,and PFJ＋CF,IPFJ＋CF.The pH value,ammonia-N,organic acid,nutrients and nitryl compound contents of 14 treatments were determined after 90 d ensiling period.Results showed that the pH,ammonia-N,lactic acid and acetic acid contents of alfalfa silage were significantly affected by rain and additives（P0.01）.Lactic acid content of IPFJ＋CF was significantly higher than that of CK and other treatments（P0.05）.There was significant effect of rain and additives on DM,NDF,ADF and buffer capacity of alfalfa silage（P0.05）.Ash,CP,EE and WSC of alfalfa silage were significantly affected by additives（P0.05）.There were highly significant effects of raining,additives and interaction on nitrate and nitrite contents of alfalfa silage（P0.01）.Additives can improve fermentation quality of rained alfalfa silage.The IPFJ＋CF was the best additive compared to all tested ones.