Mineral profile, carbohydrates fractionation, nitrogen compounds and in vitro gas production of elephant grass silages associated with cactus pear

Bulletin of the National Research Centre

Table 4 In vitro gas production of elephant grass associated with different levels of cactus pear (n = 5)

Variables	Cactus pear levels (g/kg DM)				SEM	P-value
Variables	0	150	300	450	SEM	L	Q
Vt (mL/g DM)	249.3	246.2	255.8	234.1	8.72	0.383	0.291
Vf1 (mL/g DM)	147.7	152.0	148.7	138.5	4.65	0.176	0.156
kd1 (mL/g DM/h)	0.07	0.08	0.08	0.08	0.003	0.067	0.157
Vf2 (mL/g DM)	102.5	94.0	105.2	94.8	7.98	0.749	0.912
kd2 (mL/g DM/h)	0.02	0.02	0.02	0.02	0.001	0.059	0.375
λ (h)	6.5	7.4	7.0	8.2	0.51	0.063	0.768

Vt, maximum total volume of gas produced; Vf1, maximum gas volume for the fast-digesting fraction (non-fiber carbohydrates; NFC); Vf2, maximum gas volume for the slow digested fraction (fibrous carbohydrates; FC); kd1, specific growth rate for the rapid degradation fraction; kd2, specific growth rate for the slow degradation fraction; λ (Lag time)—duration of initial digestion events (latency phase), common to both phases; SEM standard error of the mean, L linear effect, Q quadratic effect
Significance at 5% of probability