Effect of quebracho tannins supplementation on nutrients utilization and rumen fermentation characteristics in sheep

الملخص EN

This experiment was conducted to evaluate the potential impacts of commercial quebracho tannins (QT) supplementation to male Barki sheep on dry matter intake, digestion coefficients of nutrients, nitrogen balance and rumen fermentation characteristics.

Digestibility trial was carried out on Barki sheep (n=12), which were allocated into three groups (4 animals each).

The supplementation levels of QT; 0, 26 and 52 g/h/d, were mixed with the concentrate mixture.

The results showed that inclusion of 52 g/h/d of QT decreased (P<0.05) the dry matter intake, while low dose had no negative impact on dry matter intake as compared to the control group.

The low level (26 g/h/d) of QT supplementation decreased (P<0.05) digestion coefficients of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) relative to control, while the high level (52 g/h/d) of QT supplementation had no significant impacts on nutrients digestion coefficients, except improving (P<0.05) that of ether extract (EE) compared to the control and to the low level of QT supplementation.

Moreover, total digestible nutrients (TDN) and digestible crude protein (DCP) decreased (P<0.05) by inclusion of 26g QT /h/d compared to the other levels of QT.

Faecal and urinary N increased (P<0.05) when QT was supplemented at 26g/h/d as compared to the control group, while the high level of QT had no effect on faecal or urinary N execration.

Also, the low level of QT caused decrease (P<0.05) in the N balance as compared to the other levels of QT.

Inclusion of QT at 52g /h/d decreased (P<0.05) the ruminal NH3-N concentration but the reduction in volatile fatty acids (VFA) was not significant when compared to the control group.

It can be concluded that low level of QT had negative impacts on nutrients utilization and it is recommend that more studies with lower levels of QT should be conducted.