Table 3

Forages	Levels of Glycerin					Regression Equations	R²	p-value
Forages	0%	30%	50%	70%		Regression Equations	R²	p-value
Concentration of Acetate(µmol mL^-1)
Elephant grass	26.51^b	26.6^b	28.60^a	24.69^b	Ŷ =27.084+0.012x		0.01	0.8073
Sugar cane	24.89^b	22.26^b	23.00^b	21.37^b	Ŷ =24.543+0.044x		0.43	0.0206
Corn silage	37.72^a	30.27^a	25.76^b	22.11^b	Ŷ =37.399+0.224x		0.90	<.0001
Brachiaria grass	12.60^c	10.26^c	5.10^c	35.93^a	Ŷ =14.023+0.788x-0.015x2		0.79	0.0013
Concentration of Propionate (µmol mL^-1)
Elephant grass	11.76^d	22.13^b	27.79^a	18.56^b	Ŷ =11.255-0.675x-0.007x2		0.48	0.0474
Sugar cane	22.27^b	25.62^a	25.14^b	27.77^a	Ŷ =22.546-0.070x		0.45	0.0175
Corn silage	19.63^c	24.22^a	33.17^a	36.42^a	Ŷ =18.825-0.254x		0.79	0.0001
Brachiaria grass	35.37^a	25.44^a	23.34^c	39.24^a	Ŷ =30.149-0.018x		0.01	0.8279
Concentration of Butyrate (µmol mL^-1)
Elephant grass	3.343^a	5.42^a	5.80^a	4.16^a		Ŷ =3.298-0.125x-0.001x2	0.52	0.0198
Sugar cane	10.07^b	11.61^b	11.27^c	10.95^c		Ŷ =10.535-0.011x	0.05	0.4869
Corn silage	12.41^a	9.95^b	12.72^b	13.52^b		Ŷ =11.335-0.021x	0.11	0.2914
Brachiaria grass	16.61^c	22.24^c	28.10^d	32.83^d		Ŷ =16.139-0.234x	0.94	<.0001

*Means in the same column with different letters differ statistically by the Tukey test at 5% probability.

Table 3: Mean values, probability (p-value) and regression equations illustrating the effects on production of volatile fatty acids (VFAs) when different levels of glycerin.