摘要
[目的]本文旨在评价甲酸、纤维素酶和乳酸菌对水稻秸秆青贮发酵品质和结构性碳水化合物降解的影响。[方法]试验设无添加对照组(CK)、甲酸添加(6 m L·kg~(-1))组(F)、纤维素酶添加(0.5 g·kg~(-1))组(C)、乳酸菌添加1×106CFU·g~(-1)组(L)和乳酸菌+纤维素酶组合添加组(CL),添加量以鲜质量计。水稻秸秆青贮6、15、30和60 d后采集样品,分析青贮饲料发酵品质和结构性碳水化合物的组分变化。[结果]与对照组相比,添加甲酸(F组)显著提高水溶性碳水化合物含量(P<0.05),降低氨态氮/总氮值,但一定程度上抑制乳酸发酵;纤维素酶组对水稻秸秆青贮发酵品质具有一定的改善效果;添加乳酸菌L组显著提高乳酸含量和乳酸/乙酸值(P<0.05),显著降低pH值、氨态氮/总氮值和乙酸含量(P<0.05),明显改善水稻秸秆青贮发酵品质;相对于L组,CL组并没有进一步改善青贮发酵品质。整个青贮过程中,F组始终显示最低的纤维素和半纤维素含量(P<0.05),C组和CL组纤维素和半纤维素含量显著低于对照组(P<0.05),CL组纤维素和半纤维素含量又低于C组(P>0.05)。[结论]甲酸对纤维素和半纤维素降解作用最为明显,乳酸菌和纤维素酶组合添加不但提高了发酵品质,还对纤维素和半纤维素具有较为明显的降解作用。
[Objectives]The objective of this study was to evaluate the effects of formic acid,cellulase and lactic acid bacteria on fermentation quality and structural carbohydrates degradation of rice straw silage. [Methods]The treatments were ensiled with: no additive control( CK); 6 m L·kg~(-1)formic acid( F); 0.5 g·kg~(-1)cellulase( C); 1×106CFU·g~(-1)lactic acid bacteria( L); C+L( CL),based on fresh matter. The silos from each treatment were opened on 6,15,30 and 60 d of ensiling,and then the fermentation quality and structural carbohydrates compositions of rice straw silage were analyzed. [Results]Compared with the control silage,addition of formic acid significantly increased water soluble carbohydrate content( P<0.05),and decreased ammonia nitrogen/total nitrogen( P<0.05),but the lactic acid fermentation was inhibited. Rice straw added with cellulase had an improvement effect on silage quality. L treatment obviously improved the fermentation quality of rice straw silage as indicated by higher lactic acid content and lactic acid/acetic acid( P<0.05),and lower pH,ammonia nitrogen/total nitrogen and acetic acid contents than those of the control silage( P<0.05). Compared with L silage,CL treatment did not further improve the fermentation quality. F treatment showed the lowest cellulose and hemicellulose contents during ensiling( P<0.05). C and CL treatment had lower cellulose and hemicellulose contents compared with CK( P<0.05),and CL silage had lower hemicellulose and cellulose contents than C silage( P>0.05). [Conclusions]The addition of formic acid was the most effective in degrading cellulose and hemicellulose,and cellulase combination of lactic acid bacteria not only improved fermentation quality,but also degraded cellulose and hemicellulose effectively.
引文
[1]汪营,张义鹏,刘天义,等.体外发酵技术研究秸秆粗饲料营养价值及降解特性[J].畜牧与兽医,2016,48(12):24-29.Wang Y,Zhang Y P,Liu T Y,et al. Evaluation of the nutritive value and dynamic digestibility characteristics of roughage forage by in vitro fermentation[J]. Animal Husbandry&Veterinary Medicine,2016,48(12):24-29(in Chinese with English abstract).
[2]李蓓蓓,李秋凤,曹玉凤,等.玉米秸秆青贮饲料和谷草组合效应的研究[J].畜牧与兽医,2017,49(6):32-38.Li B B,Li Q F,Cao Y F,et al. Associative effects study between corn straw silage and millet straw[J]. Animal Husbandry&Veterinary Medicine,2017,49(6):32-38(in Chinese with English abstract).
[3]原现军,闻爱友,郭刚,等.添加酶制剂对西藏地区青稞秸秆和黑麦草混合青贮效果的影响[J].畜牧兽医学报,2013,44(8):1269-1276.Yuan X J,Wen A Y,Guo G,et al. Effect of adding cornzyme on fermentation and nutritive quality of mixed silage of hullessbarley straw and perennial ryegrass in Tibet[J]. Acta Veterinaria et Zootechnica Sinica,2013,44(8):1269-1276(in Chinese with English abstract).
[4] Cai Y M. Development of lactic acid bacteria inoculant for whole crop rice silage in Japan[C]//Proceedings of the International Symposium on Production and Utilization of Whole Crop Rice for Feed,2006:85-89.
[5] McD onald P,Henderson A R,Heron S J E. The Biochemistry of Silage[M]. Aberystwyth:Cambrian Printers Ltd.,1991.
[6] Jaakkola S,Huhtanen P,Hissa K. The effect of cell wall degrading enzymes or formic acid on fermentation quality and on digestion of grass silage by cattle[J]. Grass and Forage Science,2010,46(1):75-87.
[7]肖慎华,原现军,董志浩,等.添加乳酸菌制剂和糖蜜对箭筈豌豆和苇状羊茅混合青贮发酵品质的影响[J].南京农业大学学报,2016,39(6):1017-1022. DOI:10.7685/jnau.201607038.Xiao S H,Yuan X J,Dong Z H,et al. Effects of inoculant and molasses additives on fermentation quality of mixed silages of tall fescue(Festuca arundinacea Schreb.)and common vetch(Vicia sativa L.)[J]. Journal of Nanjing Agricultural University,2016,39(6):1017-1022(in Chinese with English abstract).
[8]朱春娟,原现军,董志浩,等.添加剂对饲料型四倍体刺槐青贮发酵品质和体外消化率的影响[J].南京农业大学学报,2017,40(4):725-731. DOI:10.7685/jnau.201612012.Zhu C J,Yuan X J,Dong Z H,et al. Effect of additives on fermentation quality and in vitro digestibility of tetraploid black locust(Robinia pseudoacacia L.)silage[J]. Journal of Nanjing Agricultural University,2017,40(4):725-731(in Chinese with English abstract).
[9]王奇,余成群,李志华,等.添加酶和乳酸菌制剂对西藏苇状羊茅和箭筈豌豆混合青贮发酵品质的影响[J].草业学报,2012,21(4):186-191.Wang Q,Yu C Q,Li Z H,et al. Effect of adding coenzyme and lactic acid bacteria on fermentation quality of mixed silages of tall fescue(Festuca arundinacea)and common vetch(Vicia sativa)in Tibet[J]. Acta Prataculture Sinica,2012,21(4):186-191(in Chinese with English abstract).
[10] Kung L,Carmean B R,Tung R S. Microbial inoculation or cellulase enzyme treatment of barley and vetch silage harvested at three maturities[J].Journal of Dairy Science,1990,73(5):1304-1311.
[11] Zhang Q,Yu Z,Yang H,et al. The effects of stage of growth and additives with or without cellulase on fermentation and in vitro degradation characteristics of Leymus chinensis silage[J]. Grass and Forage Science,2016,71(4):595-606.
[12]原现军,余成群,夏坤,等.添加青稞酒糟对西藏箭筈豌豆与苇状羊茅混合青贮发酵品质的影响[J].畜牧兽医学报,2012,43(9):1408-1414.Yuan X J,Yu C Q,Xia K,et al. Effect of adding wet hullessbarley distillers,grains on fermentation quality of common vetch(Vicia sativa)and tall fescue(Festuca arundinacea)in Tibet[J]. Acta Veterinaria et Zootechnica Sinica,2012,43(9):1408-1414(in Chinese with English abstract).
[13]董志浩,原现军,闻爱友,等.添加乳酸菌和发酵底物对桑叶青贮发酵品质的影响[J].草业学报,2016,25(6):167-174.Dong Z H,Yuan X J,Wen A Y,et al. Effect of lactic acid bacteria and fermentation substrates on the quality of mulberry(Morus alba)leaf silage[J].Acta Prataculture Sinica,2016,25(6):167-174(in Chinese with English abstract).
[14] Liu Q H,Shao T,Bai Y F. The effect of fibrolytic enzyme,Lactobacillus plantarum and two food antioxidants on the fermentation quality,alphatocopherol and beta-carotene of high moisture napier grass silage ensiled at different temperatures[J]. Animal Feed Science and Technology,2016,221:1-11.
[15]荣辉,陈杰,余成群,等.添加甲酸对象草青贮发酵品质的影响[J].草地学报,2012,20(6):1105-1111.Rong H,Chen J,Yu C Q,et al. Effect of adding formic acid on fermentation quality of Napier grass[J]. Acta Agrestia Sinica,2012,20(6):1105-1111(in Chinese with English abstract).
[16] Stokes M R. Effects of an enzyme mixture,an inoculant,and their interaction on silage fermentation and dairy production1[J]. Journal of Dairy Science,1992,75(3):764-773.
[17] Liu W J,Pang H L,Zhang H P,et al. Biodiversity of lactic acid bacteria[M]//Pang H L,Cai Y M. Lactic Acid Bacteria. Dordrecht:Springer,2014:103-203.
[18]原现军,王奇,李志华,等.添加糖蜜对青稞秸秆和多年生黑麦草混合青贮发酵品质及营养价值的影响[J].草业学报,2013,22(3):116-123.Yuan X J,Wang Q,Li Z H,et al. Effect of molasses addition on fermentation and nutritive quality of mixed silage of hulless barley straw and perennial ryegrass in Tibet[J]. Acta Prataculture Sinica,2013,22(3):116-123(in Chinese with English abstract).
[19] Guo G,Yuan X J,Li L X,et al. Effects of fibrolytic enzymes,molasses and lactic acid bacteria on fermentation quality of mixed silage of corn and hulless-barely straw in the Tibetan Plateau[J]. Grassland Science,2014,60(4):240-246.
[20] Yuan X,Yu C,Shimojo M,et al. Improvement of fermentation and nutritive quality of straw-grass silage by inclusion of wet hulless-barley distillers’grains in Tibet[J]. Asian-Australasian Journal of Animal Sciences,2012,25(4):479.
[21] Desta S T,Yuan X J,Li J F,et al. Ensiling characteristics,structural and nonstructural carbohydrate composition and enzymatic digestibility of Napier grass ensiled with additives[J]. Bioresource Technology,2016,221:447-454.
[22] Zhang Q,Yang H,Yu Z. Effects of sucrose,formic acid and lactic acid bacteria inoculant on quality,in vitro rumen digestibility and fermentability of drooping wild ryegrass(Elymus nutans Griseb.)silage[J]. Journal of Animal and Feed Sciences,2017,26(1):26-32.
[23] Yahaya M S,Kawai M,Takahashi J,et al. The effects of different moisture content and ensiling time on silo degradation of structural carbohydrate of orchardgrass[J]. Asian Australasian Journal of Animal Sciences,2002,15(2):1-14.
[24] Stokes M R,Chen J. Effects of an enzyme-inoculant mixture on the course of fermentation of corn silage 1[J]. Journal of Dairy Science,1994,77(11):3401-3409.
[25] Baytok E,Aksu T,Karsli M A,et al. The effects of formic acid,molasses and inoculant as silage additives on corn silage composition and ruminal fermentation characteristics in sheep[J]. Turkish Journal of Veterinary&Animal Sciences,2014,29(2):469-474.