Effect of progressive inoculation of fauna-free sheep with holotrich protozoa and total-fauna on rumen fermentation, microbial diversity and methane emissions
Effect of progressive inoculation of fauna-free sheep with holotrich protozoa and total-fauna on rumen fermentation, microbial diversity and methane emissions
复制标题
DOI：
10.1093/femsec/fiu026
复制
发表时间：
2015-03-01
影响因子：
4.2
通讯作者：
Newbold, Charles J.
中科院分区：
文献类型：
--
作者：
Belanche, Alejandro;de la Fuente, Gabriel;Newbold, Charles J.
瘤胃产甲烷是反刍动物的一种能源浪费，也是温室气体的重要来源;因此，需要进行综合研究以充分了解这一过程。选用8只无动物区系绵羊，研究了连续接种全志贺氏原生动物和动物区系对瘤胃甲烷生成的影响。接种Holotrichs既不改变瘤胃发酵率，也不改变饲料消化率，但增加了乙酸（+15%），丁酸（+57%），厌氧真菌（+0.82 log），产甲烷菌（+0.41 log）和产甲烷（+54%）的浓度。进一步接种全部动物增加瘤胃原生动物浓度（+1.0 log），细菌（+0.29 log），厌氧真菌（+0.78 log），VFA（+8%），氨和纤维消化率（+17%），而不影响产甲烷菌或产甲烷水平。瘤胃产甲烷菌种群结构和多样性较为稳定，而细菌群落结构受处理影响较大。接种全鞭毛虫原生动物增加了细菌多样性。进一步接种总动物群降低了细菌的多样性，但增加了某些丙酸和乳酸生产细菌的浓度，这表明替代H-2汇可能是相关的。本实验表明，全壁原生动物比内甲虫对瘤胃甲烷生成的影响更大。因此，进一步的研究是必要的，以了解全沟原生动物对甲烷形成的影响，并评估其消除瘤胃作为一个潜在的甲烷减排策略。
Rumen methanogenesis represents an energy waste for the ruminant and an important source of greenhouse gas; thus, integrated studies are needed to fully understand this process. Eight fauna-free sheep were used to investigate the effect of successive inoculation with holotrich protozoa then with total fauna on rumen methanogenesis. Holotrichs inoculation neither altered rumen fermentation rate nor diet digestibility, but increased concentrations of acetate (+15%), butyrate (+57%), anaerobic fungi (+0.82 log), methanogens (+0.41 log) and methanogenesis (+54%). Further inoculation with total fauna increased rumen concentrations of protozoa (+1.0 log), bacteria (+0.29 log), anaerobic fungi (+0.78 log), VFA (+8%), ammonia and fibre digestibility (+17%) without affecting levels of methanogens or methanogenesis. Rumen methanogens population was fairly stable in terms of structure and diversity, while the bacterial community was highly affected by the treatments. Inoculation with holotrich protozoa increased bacterial diversity. Further inoculation with total fauna lowered bacterial diversity but increased concentrations of certain propionate and lactate-producing bacteria, suggesting that alternative H-2 sinks could be relevant. This experiment suggests that holotrich protozoa have a greater impact on rumen methanogenesis than entodiniomorphids. Thus, further research is warranted to understand the effect of holotrich protozoa on methane formation and evaluate their elimination from the rumen as a potential methane mitigation strategy.