Table 3.

Effects of inclusion of different additives in diets with 2 levels of concentrate on fermentation parameters in a dual-flow continuous culture system

Item†	Concentrate level‡		Additives§					SEM	P-value
	Low	High	Control	Yeast cells	Blend 1	Blend 2	Monensin		Diet	Additive	Diet × Addit
Total VFA, mmol	55.2	98.2	77.9a	74.0b	78.3a	77.7a	75.7ab	1.49	<0.01	0.04	0.66
VFA profile, mol/100 mol
Acetate	72.6	46.7	60.3a	60.1a	58.5b	59.9a	59.4ab	0.46	<0.01	<0.01	0.77
Propionate	16.7	36.8	26.2b	26.2b	27.2a	26.9ab	27.1a	0.61	<0.01	0.02	<0.01
Butyrate	7.41	10.7	9.07	9.09	8.85	9.04	9.28	0.44	<0.01	0.64	0.74
Iso-butyrate	0.74	0.28	0.51	0.51	0.51	0.52	0.51	0.01	<0.01	0.89	0.28
Valerate	1.19	5.01	3.10ab	3.28a	3.16ab	2.95c	3.02bc	0.22	<0.01	0.01	<0.01
Iso-valerate	1.07	0.51	0.83ab	0.85a	0.76c	0.77bc	0.74c	0.55	<0.01	<0.01	<0.01
BCVFA	1.82	0.79	1.34ab	1.37a	1.27bc	1.29bc	1.25c	0.06	<0.01	0.01	<0.01
Acetate:propionate	4.37	1.28	2.90a	2.84ab	2.81b	2.81b	2.77b	0.65	<0.01	0.04	0.02
NH3–N, mg/100 mL	0.69	1.30	1.02ab	0.98ab	0.88b	1.09a	1.03ab	0.17	<0.01	0.17	0.04
pH	6.84	5.40	612	6.07	6.14	6.13	6.15	0.06	<0.01	0.15	0.56

^a,b,cDifferent letters on the same line indicate significant differences between means related to additives (P < 0.05).

^†VFA = Volatile fatty acids; BCVFA = Branched-chain volatile fatty acids; SEM = Standard error of the mean.

^‡High (80% concentrate), low (20% concentrate).

^§Control—diet without additive inclusion; Yeast cells (Saccharomyces cerevisiae) hydrolyzed, inactivated, and dried by spray at 2,133 mg/kg DM (BioHydro Yessinergy LTDA, Campinas, SP, Brazil); Blend 1—yeast culture (Saccharomyces cerevisiae), beta-glucans, fructooligosaccharides, galactooligosaccharides, and mannanoligosaccharides at 1,600 mg/kg DM (Golf Yessinergy LTDA, Campinas, SP, Brazil); Blend 2—beta-glucan and mannanoligosaccharide fractions from Saccharomyces cerevisiae at 1,600 mg/kg DM (GlucanMos Yessinergy LTDA, Campinas, SP, Brazil); Monensin (Rumensin, 25 mg/kg DM).