Table 4.

Effects of tannins on productivity of monogastric animals.

Tannin Concentrations	Tannin Source	Monogastric Animal	Influenced/Affected Parameter	References
0.16–0.19%	Chestnut	Pigs	Increased growth performance	[4]
0.71–1.5%	Chestnut	Pigs	No effect on feed intake, body weight gain and carcass traits; reduced feed efficiency	[81]
1–3%	Chestnut	Pigs	Increased small intestinal villus height, villus perimeter and mucosal thickness	[70]
5–10%	Grape pomace	Broilers	No effect on growth performance; increased oxidative stability and polyunsaturated fatty acids content of thigh meat	[75]
1%	Tannic acid	Broilers	Decreased body weight gain and feed intake; improved the fatty acid profile of breast muscle	[71]
	Chestnut	layers	No effect on egg weights, cell thickness or yolk colour; reduced cholesterol content	[72]
0.45% and 0.5%	Chestnut	Rabbits	Increased live weight gain and feed intake of rabbits	[79,86]
0.5% and 1.0%	Quebracho and chestnut	Rabbits	Had no effect on growth performance	[62,84]
4%	Acacia karroo, Acacia nilotica and Acacia tortilis	Rabbits	No significant differences in intake and digestibility	[83]