Table 1.

Box Behnken design for the evaluation of effects of protected fat, choline and yeast extract on in vitro rumen fermentation parameters

Runs	Variable
	Protected fat		Choline		Yeast
	Coded	Uncoded (%)	Coded	Uncoded (%)	Coded	Uncoded (%)
1	−1	0.01	−1	0.0005	0	0.01
2	1	0.1	−1	0.0005	0	0.01
3	−1	0.01	1	0.01	0	0.01
4	1	0.1	1	0.01	0	0.01
5	−1	0.01	0	0.0015	−1	0.005
6	1	0.1	0	0.0015	−1	0.005
7	−1	0.01	0	0.0015	1	0.05
8	1	0.1	0	0.0015	1	0.05
9	0	0.02	0	0.0005	−1	0.005
10	0	0.02	1	0.01	−1	0.005
11	0	0.02	−1	0.0005	1	0.05
12	0	0.02	0	0.01	1	0.05
13	0	0.02	0	0.0015	0	0.01
14	0	0.02	0	0.0015	0	0.01
15	0	0.02	0	0.0015	0	0.01