Microbial interactions with tannins: nutritional consequences for ruminants

• Published in: Animal feed science and technology 2001-05, Vol.91 (1), p.83-93
• Main Authors: McSweeney, C.S, Palmer, B, McNeill, D.M, Krause, D.O
• Format: Article
• Language: English
• Subjects: Animal productions; Animal, plant and microbial ecology; Biological and medical sciences; Ecology; Fundamental and applied biological sciences. Psychology; Microbial; Microbial ecology; Normal microflora of man and animals. Rumen; Rumen; Tannin; Terrestrial animal productions; Vertebrates
• ISSN: 0377-8401; 1873-2216
• DOI: 10.1016/S0377-8401(01)00232-2

Polyphenolics are widely distributed in the plant kingdom and are often present in the diet of herbivores. The two major groups of plant polyphenolic compounds other than lignin are condensed and hydrolysable tannins. These compounds can have toxic and/or antinutritional effects on the animal. It is well established that tannins complex with dietary proteins can reduce nitrogen supply to the animal, but the ability of gastrointestinal microorganisms to metabolise these compounds and their effects on microbial populations have received little attention. In this paper, we review recent literature on the topic as well as present research from our laboratories on the effect of condensed tannins on rumen microbial ecology and rumen metabolism. Interactions of tannins with dietary components and endogenous protein in the rumen and post-ruminally, and their impact on the nutrition of the animal are considered.