瘤胃微生物对苜蓿茎降解特性及超微结构的影响

徐俊; 侯玉洁; 赵国琦; 霍永久; 邬彩霞

doi:10.3969/j.issn.1006-267x.2014.03.030

动物营养学报 >

2014 , Vol. 26 >Issue 3: 776 - 782

DOI: https://doi.org/10.3969/j.issn.1006-267x.2014.03.030

研究简报 Short Communications

瘤胃微生物对苜蓿茎降解特性及超微结构的影响

徐俊 ,
侯玉洁 ,
赵国琦 ,
霍永久 ,
邬彩霞

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扬州大学动物科学与技术学院, 扬州 225009

收稿日期: 2013-09-25

网络出版日期: 2014-03-04

基金资助

江苏省研究生科研创新计划（CXLX12_0933）；十二五国家科技支撑计划（2011BAD17B03）

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Effects of Rumen Microorganisms on Degradation Characteristics and Ultrastructure of Alfalfa Stem

XU Jun ,
HOU Yujie ,
ZHAO Guoqi ,
HUO Yongjiu ,
WU Caixia

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College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China

Received date: 2013-09-25

Online published: 2014-03-04

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摘要

本试验旨在研究瘤胃微生物对苜蓿茎降解特性及超微结构的影响。选用长势和株高相近的初花期苜蓿茎进行尼龙袋降解率试验，并截取第2节茎均分为6份，在瘤胃中分别降解6、12、24、48和72 h，利用扫描电镜和透射电镜观察其超微结构变化。结果表明：1）苜蓿茎干物质和中性洗涤纤维在瘤胃中的降解主要发生在24 h内，且在48 h后中性洗涤纤维只有很少部分被降解。2）非木质化的表皮、厚角组织、绿色组织、形成层、初生韧皮部和初生木质部薄壁组织均可在瘤胃微生物作用下快速降解，且在24 h时已完全降解，但木质化程度高的次生木质部纤维及导管几乎不能被降解。3）带荚膜球菌和不规则形状菌是降解纤维组织的主要细菌，且不同组织结构在微生物作用下的降解规律存在差异。由此可见，苜蓿茎在瘤胃微生物作用下可快速降解，但降解速率及程度受其组织结构及组分的影响，而高度木质化的结构在瘤胃中难以降解，提示了降低高度木质化组分含量是提高苜蓿茎降解率的有效途径。

关键词： 苜蓿茎; 扫描电镜; 透射电镜; 超微结构

本文引用格式

徐俊 , 侯玉洁 , 赵国琦 , 霍永久 , 邬彩霞 . 瘤胃微生物对苜蓿茎降解特性及超微结构的影响[J]. 动物营养学报, 2014 , 26(3) : 776 -782 . DOI: 10.3969/j.issn.1006-267x.2014.03.030

Abstract

This study was conducted to investigate the effects of rumen microorganisms on degradation characteristics and ultrastructure of alfalfa stem. Alfalfa stems with similar growth profile and plant height were harvested at early flowering to carried out a degradation rate experiment using nylon bags, at the same time, the second internode was longitudinally cut to six equal parts for samples which were incubated for 6, 12, 24, 48 and 72 h in the rumen, repectively. The changes of ultrastructure of alfalfa stem were observed under scanning and transmission electron microscopes. The results showed as follows: 1) dry matter and neutral detergent fiber were mostly degraded within 24 h of fermentation in rumen, and only a small part of neutral detergent fiber was degraded after 48 h. 2) The non-lignified epidermis, collencyma, chlorenchyma, cambium and primary xylem parenchyma were all quickly degraded, and completely degraded within 24 h of fermentation in rumen, but the lignified secondary xylem fiber and vessels remained undegraded. 3) Encapsulated cocci and irregularly shaped bacteria were the majorities of fiber digesters, and the degradation regularity was various with different structure of tissues. In conclusion, alfalfa stem can be rapidly degraded under the effects of rumen microorganisms, but the rate and content of degradation are related to the structure and composition of alfalfa stem, in addition, the highly lignified structures are difficult to be degraded in the rumen. Therefore, reducing the content of lignification composition is an effective method to improve degradation rate of alfalfa stem.

Key words： alfalfa stem; scanning electron microscopy; transmission electron microscopy; ultrastructure

参考文献

[1] HOLT M, EUN J S, THACKER C, et al.Effects of feeding brown midrib corn silage with a high dietary concentration of alfalfa hay on lactational performance of Holstein dairy cows for the first 180 days of lactation[J].Journal of Dairy Science, 2012, 96(1):515-523.

[2] MOWAT D, FULKERSON R, TOSSELL W, et al.The in vitro digestibility and protein content of leaf and stem portions of forages[J].Canadian Journal of Plant Science, 1965, 45(4):321-331.

[3] MOSONI P, FONTY G, GOUET P.Competition between ruminal cellulolytic bacteria for adhesion to cellulose[J].Current Microbiology, 1997, 35(1):44-47.

[4] JUNG H, ENGELS F.Alfalfa stem tissues:rate and extent of cell wall thinning during ruminal degradation[J].NJAS-Wageningen Journal of Life Sciences, 2001, 49(1):3-13.

[5] ENGELS F M, JUNG H J G.Alfalfa stem tissues:impact of lignification and cell length on ruminal degradation of large particles[J].Animal Feed Science and Technology, 2005, 120(3):309-321.

[6] AKIN D E, AMOS H E.Rumen bacterial degradation of forage cell walls investigated by electron microscopy[J].Applied Microbiology, 1975, 29(5):692-701.

[7] ØRSKOV E R, MCDONALD I.The estimation of protein degradability in the rumen from incubation measurements weighted according to rate of passage[J].The Journal of Agricultural Science, 1979, 92(2):499-503.

[8] 冯仰廉, 莫放.反刍动物蛋白质营养的新体系[M].动物营养研究进展, 1994, 65-83.

[9] ENGELS F, JUNG H.Alfalfa stem tissues: cell wall development and lignification[J].Annals of Botany, 1998, 82(5):561-568.

[10] FERNANDO W M, FLINT S, BRENNAN C S, et al.The influence of environmental factors on the adhesion of combinations of probiotics to rice fibre fractions[J].World Journal of Microbiology and Biotechnology, 2012, 28(6):2293-2302.

[11] LYND L R, WEIMER P J, VAN ZYL W H, et al.Microbial cellulose utilization:fundamentals and biotechnology[J].Microbiology and Molecular Biology Reviews, 2002, 66(3):506-577.

[12] AKIN D E.Evaluation by electron microscopy and anaerobic culture of types of rumen bacteria associated with digestion of forage cell walls[J].Applied and Environmental Microbiology, 1980, 39(1):242-252.

[13] JUNG H J, SAMAC D A, SARATH G.Modifying crops to increase cell wall digestibility[J].Plant Science, 2012, 185:65-77.

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