菠萝皮与不同比例王草和百香果藤混合青贮研究

Study on Mixed Silage of Pineapple Peel with Different Proportions ofKing Grass and Passion Fruit Vine

本试验旨在探究菠萝皮、王草和百香果藤不同混合比例对青贮饲料发酵品质和微生物多样性的影响。以菠萝皮、王草和百香果藤为原料,将三者分别按鲜重比3∶6∶1、3∶5∶2、3∶4∶3、3∶3∶4和3∶2∶5分为5个组进行混合青贮,在室温条件下青贮40 d后,对青贮饲料的发酵品质、营养成分含量和微生物多样性进行分析。结果表明:1)随着百香果藤混合比例的提高,青贮饲料pH以及氨态氮(NH 3-N)和丁酸(BA)含量呈提高趋势,其中3∶6∶1组pH最低,显著低于除3∶5∶2组外的其他组(P<0.05);且3∶6∶1组NH 3-N和BA含量显著低于其他各组(P<0.05)。此外,各组青贮饲料的品质得分评价均为好,其中3∶6∶1组品质得分最高。2)随着百香果藤混合比例的提高,青贮饲料干物质(DM)和粗蛋白质(CP)含量呈提高趋势,其中3∶2∶5组DM含量显著高于3∶6∶1组和3∶5∶2组(P<0.05),CP含量显著高于除3∶3∶4组外的其他各组(P<0.05);青贮饲料中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量呈降低趋势,其中3∶6∶1组NDF含量显著高于其他各组(P<0.05),ADF含量显著高于3∶3∶4组和3∶2∶5组(P<0.05)。3)随着百香果藤混合比例的提高,青贮饲料微生物群落香农指数呈降低趋势,其中3∶6∶1组香农指数显著高于3∶2∶5组(P<0.05);青贮饲料微生物群落Ace指数呈先升高后降低的趋势,其中3∶5∶2组Ace指数显著高于3∶3∶4组和3∶2∶5组(P<0.05)。青贮结束后,3∶6∶1组、3∶5∶2组和3∶2∶5组的优势菌门和优势菌属分别为厚壁菌门(Firmicutes)和乳杆菌属(Lactobacillus),而3∶4∶3组和3∶3∶4组的优势菌门和优势菌属分别为变形菌门(Proteobacteria)和泛菌属(Pantoea)。综上所述,3∶6∶1组青贮饲料发酵效果最好,在青贮生产实践中推荐菠萝皮、王草和百香果藤的混合比例为3∶6∶1。

This experiment was conducted to investigate the effects of different mixing ratios of pineapple peel,king grass and passion fruit vine on fermentation quality and microbial diversity of silage.Mixed silage with pineapple peel,king grass and passion fruit vine were divided into 5 groups according to fresh weight ratios of 3∶6∶1,3∶5∶2,3∶4∶3,3∶3∶4 and 3∶2∶5,respectively.The fermentation quality,nutrient contents and microbial diversity of silage were analyzed after silage at room temperature for 40 days.The results showed as follows:1)with the increase of the mixed proportion of passion fruit vine,the pH and the contents of ammonia nitrogen(NH 3-N)and butyric acid(BA)in silage showed an increasing trend,and the pH in 3∶6∶1 group was the lowest,which was significantly lower than that in the other groups except 3∶5∶2 group(P<0.05);the contents of NH 3-N and BA in 3∶6∶1 group were significantly lower than those in the other groups(P<0.05).In addition,the Flieg point evaluation of silage in all groups was good,and the Flieg point in 3∶6∶1 group was the highest.2)With the increase of the mixed proportion of passion fruit vine,the contents of dry matter(DM)and crude protein(CP)in silage showed an increasing trend,the DM content in 3∶2∶5 group was significantly higher than that in 3∶6∶1 and 3∶5∶2 groups(P<0.05),and the CP content was significantly higher than that in the other groups except 3∶3∶4 group(P<0.05);the contents of neutral detergent fiber(NDF)and acid detergent fiber(ADF)in silage showed a decreasing trend,the NDF content in 3∶6∶1 group was significantly higher than that in the other groups(P<0.05),and the ADF content was significantly higher than that in 3∶3∶4 and 3∶2∶5 groups(P<0.05).3)With the increase of the mixed proportion of passion fruit vine,the Shannon index of microbial community in silage showed a decreasing trend,and the Shannon index in 3∶6∶1 group was significantly higher than that in 3∶2∶5 group(P<0.05);the Ace index of microbial community in silage was firstly increased and then decreased,and the Ace index in 3∶5∶2 group was significantly higher than that in 3∶3∶4 and 3∶2∶5 groups(P<0.05).After silage,the dominant bacteria in 3∶6∶1,3∶5∶2 and 3∶2∶5 groups at phylum and genus levels were Firmicutes and Lactobacillus,while the dominant bacteria in 3∶4∶3 and 3∶3∶4 groups at phylum and genus levels were Proteobacteria and Pantoea,respectively.In conclusion,the fermentation effects on silage in 3∶6∶1 group is the best,and the recommended mixing ratio of pineapple peel,king grass and passion fruit vine is 3∶6∶1 in silage production.