The impact of condensed tannins from dock (Rumex obtusifolius) on the growth of rumen proteolytic bacteria in vitro
Dock (Rumex obtusifolius) is commonly regarded as a weed, but it prevents bloat in cattle and the condensed tannins (CT) in dock are able to reduce the viability of gastrointestinal parasite eggs and larvae under in vitro conditions. These benefits, with other attributes of CT from a variety of forages promoted this study to examine effects of CT extracted from dock on the growth of five strains of proteolytic rumen bacteria in vitro. Streptococcus bovis NCFB 2476, Eubacterium sp. C124b, Prevotella bryantii B14, Butyrivibrio fibrisolvens H17c and Clostridium proteoclasticum B316T were tested against 200, 400 and 600 μg CT/ml. In the absence of CT, all bacterial strains showed typical growth and reached maximum optical density (OD 600 nm) after 6-8 h of incubation at 39 C. All strains continued to grow in the presence of 200 μg of the CT from dock per ml but attained significantly lower (P＜0.001) OD 600 nm values than their counterparts in the control incubation. The addition of 400 and 600 μg CT/ml reduced (P＜0.001) the growth of all bacterial strains tested compared to controls. All strains except P. bryantii did not initiate growth after the addition of 600 μg/ml relative to the growth before addition of CT. C. proteoclasticum was the most sensitive to the action of CT followed by B. fibrisolvens, S. bovis, Eubacterium sp. and P. bryantii. These results suggest that the dock CT have the ability to modify the growth of rumen proteolytic bacteria either directly or indirectly by preventing access to the protein.
dock condensed tannins rumen bacteria
A.L.Molan G.T.Attwood W.C.McNabb
Institute of Food, Nutrition and Human Health, Massey University Palmerston North, New Zealand Food, Metabolism and Microbiology, Food & Health Group, AgResearch Limited, Grasslands Research Cent
国际会议
The 7tb International Symposium on the Nutrition of Herbivores(ISNH-7)(第七届国际草食动物营养研讨会)
北京
英文
617-623
2007-09-16（万方平台首次上网日期，不代表论文的发表时间）