. 2015 Oct;28(10):1449–1453. doi: 10.5713/ajas.15.0016

Table 3.

Gas production (GP) and fermentation parameters of mixed substrates with pelletized broccoli byproducts (PBB) at different levels of substitution after incubation at 24 h

	PBB	Levels of PBB (%, DM basis)

		0	10	20	30	40	SEM
GP parameters¹
GP (mL)	37.4	43.0^a	42.0^a	40.5^ab	39.9^ab	37.5^bc	1.88
a+b (mL)	35.9	47.5^a	46.3^ab	46.8^ab	43.8^c	44.9^bc	0.70
c (%/h)	7.7	7.6^a	6.9^ab	7.3^ab	6.6^b	5.3^c	0.14
Fermentation parameters
pH	6.81	6.88	6.87	6.86	6.87	6.86	0.024
Ammonia-N (mg/dL)	29.5	25.6^ab	25.0^b	27.2^a	26.8^a	26.9^a	0.42
Total VFA (mmol/L)	48.2	34.9^c	35.5^bc	35.3^bc	37.3^a	36.4^ab	0.28
Proportion (mmol/100 mmol)
Acetate (%)	75.0	75.4^b	76.3^ab	76.6^ab	77.2^ab	78.0^a	0.81
Propionate (%)	17.0	16.1^a	15.7^ab	15.5^ab	15.3^ab	14.9^b	0.18
Butyrate (%)	8.0	8.5	8.1	7.8	7.5	7.1	0.35
Ac:Pro ratio	4.4	4.7^b	4.9^ab	4.9^ab	5.0^ab	5.1^a	0.03

SEM, standard error of the mean; VFA, volatile fatty acid; Ac:pro, acetate:propionate.

a, b and c: constants in the model GP = a+b (1−e⁻^c^t) (Ørskov et al., 1980).

^{a, b, c}

Means within the same row with different superscripts differ significantly (p<0.05).