Chemical composition of rumen microbial fraction and fermentation parameters as affected by tannins and saponins using an in vitro rumen fermentation system

Abstract

Castro-Montoya, J. M., Makkar, H. P. S. and Becker, K. 2011. Chemical composition of rumen microbial fraction and fermentation parameters as affected by tannins and saponins using an in vitro rumen fermentation system. Can. J. Anim. Sci. 91: 433–448. Post-rumen chemical composition of the microbial fraction is one of the factors that determines the nutrients absorbed and available for maintenance and production of the animal. The hypothesis was that tannins and saponins alter chemical composition of rumen microbes and fermentation parameters in the rumen. Purified quebracho, mimosa, chestnut and sumach tannins; and quillaja and gypsophilla saponins were incubated with 380 mg of substrate (hay:concentrate 70:30 wt/wt) for 24 h in an in vitro gas production system at concentrations from 0.25 to 1.25 mg mL−1. Saponins increased N and reduced sugar contents of the liquid-associated microbes. The ratio of crude protein to purine bases significantly increased on adding sumach and chestnut tannins and decreased on the addition of quebracho and mimosa tannins. Quebracho, mimosa and chestnut tannins reduced total short-chain fatty acid production. The acetate:propionate ratio decreased for all additives. Results suggest that in vitro (a) depending on the source and the concentration, tannins would have an effect on the nitrogen and sugar contents of the liquid associated microbes, (b) saponins are likely to increase N and reduce sugar contents of rumen liquid associated microbes, and (c) estimation of microbial protein synthesis based on purine bases may lead to under- or over-estimations in the presence of tannins and saponins. In vivo studies are required to validate these results.

Impact of Different Plant Secondary Metabolites Addition: Saponin, Tannic Acid, Salicin and Aloin on Glucose Anaerobic Co-Digestion

“…That explained why the yields of biogas were lower than those of the mixtures of Gl and Sap. This phenomenon was in accordance with that observed in the degradation of feed when the tannins are used as described in the literature [25,34,37,38]. However, it was observed higher methane yields than those of mixtures of Gl with Sap.…”

Rumen Microbiology: An Overview

“…In the rumen, CH 4 is produced by methanogens using H 2 to reduce CO 2 . The non-methanogenic hydrogenotrophic bacteria residing in the rumen include acetogens that reduce CO 2 to form acetate by the Wood-Ljungdahl pathway (i.e., reductive aceto- Ciliate protozoa 10 4-6 g −1 (25 genera) Source: Adapted from Mackie et al ( 1999 ), Castro-Montoya et al ( 2011 ) genesis), sulfate-reducing bacteria (SRB) that reduce sulfate to H 2 S (Morvan et al 1996 ), and bacteria that use H 2 to reduce fumarate to succinate (Asanuma and Hino 2000 ). Succinate, the product of fumarate reduction, is decarboxylated to propionate, a valuable animal nutrient (Wollin et al 1997 ).…”

Effects of monensin on the chemical composition of the liquid associated microbial fraction in an in vitro rumen fermentation system

“…After incubation for 24 h gas, methane, protozoa number, true dry matter digestibility (TDMD) and SCFA were determined as described in Castro-Montoya et al (2011). Partitioning factor (PF) and microbial mass production were calculated as described by Blümmel et al (1997).…”