Table 2 Effect of the tannin-essential oil mixtures Q-2 and C-10 compared to negative control (NC) and positive control (PC) on production, composition and yield of ruminal gases

Daily production

 GP, L

3.41^a

3.19^b

3.26^ab

3.20^b

0.052

0.025

 CO₂, L

1.40^a

1.18^b

1.24^ab

1.24^ab

0.044

0.005

 CH₄, mL

187^a

164^b

175^ab

166^b

5.4

0.018

 H₂, mL

6.58^a

1.54^b

5.72^a

4.69^a

2.189

 < 0.001

 CH₄/CO₂, mL/L

135^c

139^b

144^ab

134^c

1.4

 < 0.001

% of GP

 CO₂

40.9^a

36.5^c

37.4^bc

39.6^ab

0.77

 < 0.001

 CH₄

5.52

5.09

5.40

5.32

0.112

0.119

 H₂

0.19^a

0.05^b

0.17^a

0.14^a

0.063

 < 0.001

CH₄ yield

 mL/g dry matter

14.1^a

12.5^ab

13.1^ab

12.4^b

0.41

0.029

 mL/g disappeared organic matter

31.0

29.4

30.1

28.1

1.02

0.287

 mL/g disappeared neutral detergent fibre

82.5^b

83.0^b

118.4^a

100.5^ab

5.45

 < 0.001

 mL/mmol volatile fatty acids

2.21

2.23

2.41

2.06

0.101

0.173