Cao Bin-Bin, Jin Xin, Yang Hong-Jian, Li Sheng-Li, Jiang Lin-Shu
State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China.
Beijing Key Laboratory for Dairy Cow Nutrition, Beijing University of Agriculture, Beijing, 102206, China.
J Sci Food Agric. 2016 Jan 30;96(2):650-5. doi: 10.1002/jsfa.7136. Epub 2015 Mar 3.
Ferulic acid (FA) and p-coumaric acid (PCA) are widely distributed in graminaceous plant cell walls. This study investigated the in vitro and in vivo digestibility of ester-linked FA (FAest) and PCA (PCAest) in lactating dairy cows.
Regarding corn stover, ensiled corn stover, whole corn silage, Chinese wild ryegrass and alfalfa hay with different phenolic acid profiles, the in vitro rumen digestibility of forage FAest and PCAest was negatively correlated with the ether-linked FA content and original PCA/FA ratio in the forages. The concentration of both phenolic acids in culture fluids was low after a 72 h incubation, and the mixed rumen microorganisms metabolized nearly all phenolic acids released into the culture fluids. FAest digestibility in the whole digestive tract was negatively correlated with dietary PCA/FA ratio, but a converse result occurred with dietary PCAest digestibility. The digestibility in either the rumen or the whole digestive tract was greater for FAest than for PCAest.
Forage PCAest in comparison with FAest is not easily digested in either the rumen or the whole digestive tract, and they were negatively affected by forage FAeth content and lignification extent indicated by the original dietary PCA/FA ratio.
阿魏酸（FA）和对香豆酸（PCA）广泛分布于禾本科植物细胞壁中。本研究调查了泌乳奶牛中酯键连接的FA（FAest）和PCA（PCAest）的体外和体内消化率。
对于具有不同酚酸谱的玉米秸秆、青贮玉米秸秆、全株玉米青贮、中华羊茅和苜蓿干草，饲草FAest和PCAest的体外瘤胃消化率与饲草中醚键连接的FA含量和原始PCA/FA比值呈负相关。经过72小时培养后，培养液中两种酚酸的浓度都很低，混合瘤胃微生物几乎代谢了释放到培养液中的所有酚酸。全消化道中FAest的消化率与日粮PCA/FA比值呈负相关，但日粮PCAest消化率则相反。瘤胃或全消化道中FAest的消化率均高于PCAest。
与FAest相比，饲草PCAest在瘤胃或全消化道中都不容易被消化，并且它们受到饲草FAeth含量和原始日粮PCA/FA比值所表明的木质化程度的负面影响。
