Goat tannins

Several mechanisms have been proposed to explain the antimicrobial properties of tannins. The antimicrobial effects of phenolic compounds are probably related to the inhibition of bacterial enzymes, alterations in cell wall permeability, an increase in the hydrogen ion activity of the microbial environment, a reduction in the surface and/or interfacial tension and perhaps chelation of essential minerals, particularly iron with a concomitant impairment of the microbial oxidative metabolic system (Chung et al. 1998). The antimicrobial activities of tannins are ascribed to the interactions of goats tannins with the extracellular enzymes secreted and... 

Min, B. R., Pomroy, W. E., Hart, S. P. and Sahlu, T. (2004). The effect of short-term consumption of a forage containing condensed tannins on gastro-intestinal nematode parasite infections in grazing wether goats . Small Ruminant Research, 44, 81-87. 

Browsers such as mule deer, 0. hcmionus, have proUne-rich salivary proteins that bind tannins this enables them to feed on tanniniferous plants (Robbins etal, 1991). By contrast, grazers such as sheep and cattle do not possess tanninbinding proteins (Austin etal, 1989 Robbins etal, 1991), and neither do mixed feeders such as goats (Distel and Provenza, 1991). Rat and mouse saliva also contain proline-rich proteins that bind tannins. In human saliva, about 70% of total protein is rich in proline (Fig. 11.9) (Mehansho etal, 1987). 

Streptococcus sp. KNl Goat Cocci Positive TA, 30 Desmodium tannins, 0.8 - Nelson et al. (1998)... 

Animut G, Goetsch AL, Puchala R, Patra AK, Satilu T, Varel VH, Wells J (2008a) Methane emission by goats consuming diets with different levels of condensed tannins from lespedeza. Anim Peed Sci Technol 144 212-227... 

Bhatta R, Krishnamoorthy U, Mohammed F (2001) Effect of tamarind Tamarindus indica) seed husktarmins on in vitro rumen fermentation. Anim Feed Sci Technol 90 143-152 Brooker JD, O Donovan LA, Skene I, Clarke K, BlackaU L, Muslera P (1994) Streptococcus caprinus sp. nov., a tannin-resistant mminal bacterium from feral goats. Lett Appl Microbiol 18 313-318... 

Provenza, F.D., E.A. Burritt, T.P. Clausen, J.P. Bryant, P.B. Reichardt R.A. Distel. 1990. Conditioned flavor aversion a mechanism for goats to avoid condensed tannins in black brush. Am. Nat. 136 810-828. 

Animut, G., R. Puchala, A.L. Goetsch, A.K. Patra, T. Sahlu, V.H. Varel and J. Wells, 2008a. Methane emission by goats consuming different sources of condensed tannins. Anim. Feed Sci. Technol. 144,228-241. 

Puchala, R, B.R. Min, A.L. Goetsch and T. Sahlu, 2005. The effect of a condensed tannin-containing forage on methane emission by goats. J. Anim. Sci. 83, 182-186. 

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