The effects of dried pistachio (Pistachio vera L.) by-product addition on corn silage fermentation and in vitro methane production

Figures & data

Table 1. Chemical composition, condensed tannin content, methane production, IVOMD and ME of corn ensiling material and DPB.

Chemical composition	CM	DPB
DM	30.82	93.40
Ash	5.93	15.79
CP	8.22	9.43
NDF	61.85	29.19
ADF	34.18	23.15
CT	2.29	26.17
CH4	12.51	1.77
IVOMD	68.40	61.79
ME	8.92	7.11

Notes: CM: corn ensiling material; DPB: dried pistachio by-product; DM: dry matter, %; Ash: crude ash, %; CP: crude protein, %; NDF: neutral detergent fiber, %; ADF: acid detergent fiber, %; CT: condensed tannin, g/kg DM; CH₄: methane, as a percentage of total gas production, %; IVOMD :in vitro organic matter digestibility, %; ME: metabolisable energy, MJ/kg DM.

Table 2. Effect of different levels of DPB on silage nutrient composition.

Item	Treatments						SEM
	Control	2% DPB	4% DPB	6% DPB	8% DPB	10% DPB
DM	29.40^d	29.61^d	30.75^c	31.61^b	31.41^b	32.42^a	0.182
Ash	6.98^d	7.14^cd	7.33^bc	7.52^b	7.90^a	7.88^a	0.118
CP	8.22^b	8.46^b	8.28^b	8.39^b	8.79^a	8.72^a	0.079
NDF	57.19^a	55.69^b	56.22^ab	56.21^ab	56.15^ab	55.40^b	0.503
ADF	30.37^d	31.20^cd	31.63^bc	32.24^ab	32.82^a	33.06^a	0.330

Notes: ^a–dValues in the same row without a common superscript letter are significantly different (P < 0.05). DPB: dried pistachio by-product; DM: dry matter, %; Ash: crude ash, %; CP: crude protein, %; NDF: neutral detergent fiber, %; ADF: acid detergent fiber, %.

Table 3. Effect of different levels of DPB on pH, organic acids and ammonia nitrogen content of silages.

Item	Treatments						SEM
	Control	2% DPB	4% DPB	6% DPB	8% DPB	10% DPB
pH	3.89^b	3.85^c	3.92^ab	3.93^ab	3.86^c	3.91^ab	0.011
AA	16.21^a	15.76^ab	14.91^abc	13.92^cd	13.16^d	14.26^bcd	0.519
PA	0.34^d	0.47^a	0.44^ab	0.40^c	0.42^bc	0.41^c	0.01
LA	69.70	70.81	70.89	69.43	70.21	69.12	0.704
BA	ND	ND	ND	ND	ND	ND	ND
NH3-N	3.36^a	3.03^b	2.44^c	1.82^d	1.84^d	1.69^d	0.09

Notes: ^a–dValues in the same row without a common superscript letter are significantly different (P < 0.05). DPB: dried pistachio by-product; pH: pH value; AA: acetic acid, g/kg DM; PA: propionic acid, g/kg DM; ND: not detected; LA: lactic acid, g/kg KM; BA: butyric acid, g/kg KM; NH₃-N: ammonia nitrogen, NH₃-N/TN.

Table 4. Effect of different levels of DPB on in vitro gas and methane production.

Item	Treatments						SEM
	Control	2% DPB	4% DPB	6% DPB	8% DPB	10% DPB
GP	251.70^a	225.26^b	203.95^c	227.40^b	211.67^bc	196.76^c	5.550
CH4	12.11^a	10.95^b	10.96^b	10.32^c	9.82^d	8.44^e	0.169
IVOMD	70.26^a	65.88^b	62.15^cd	66.49^b	64.57^bc	61.62^d	0.957
ME	9.69^a	9.01^b	8.41^c	9.07^b	8.68^bc	8.27^c	0.149

Notes: ^a-eValues in the same row without a common superscript letter are significantly different (P < 0.05). DPB: dried pistachio by-product; GP: 24 h gas production ml/g DM; CH₄: methane production as a percentage of total gas production, %; IVOMD: in vitro organic matter digestibility, %; ME: metabolizable energy, MJ/kg DM.