The Effects of Adding Lactic Acid Bacteria and Cellulase in Oil Palm (Elais Guineensis Jacq.) Frond Silages on Fermentation Quality, Chemical Composition and in Vitro Digestibility

Figures & data

Table 1. Selected indexes of fermentation of oil palm frond, before and after an ensiling period of 12 weeks.

	Before ensiling	Experimental silages				SEM	P
		No additive	LAB	Cellulase	LAB+cellulase
LAB, log10 cfu/g	6.05	6.28^b	7.22^a	6.92^a	7.02^a	0.09	0.001
WSC, g/kg DM	10.57	3.18^d	4.67^c	6.10^b	7.56^a	0.57	0.001
Lactic acid, g/kg DM	nd	9.19^d	15.05^b	12.02^c	19.68^a	0.67	0.001
pH	6.12	4.88^a	4.18^b	4.28^b	4.09^c	0.11	0.001
NH3-N, g/100 g total N	1.58	9.9^a	8.3^b	7.9^b	6.7^b	0.55	0.017
Ethanol, g/kg DM	4.72	7.58^c	9.01^bc	10.41^b	12.50^a	0.36	0.001
Acetic acid, g/kg DM	2.46	32.74^a	18.72^b	21.18^b	23.30^ab	1.74	0.001
Propionic acid, g/kg DM	0.51	166^b	3.16^a	3.13^a	3.35^a	0.18	0.001
Butyric acid, g/kg DM	0.03	1.10^a	0.62^b	0.67^b	0.58^b	0.09	0.001
Acetic acid:propionic acid	4.80	19.72^a	5.92^b	6.76^b	6.96^b	0.39	0.001

LAB, lactic acid bacteria; WSC, water soluble carbohydrates; nd, not detected (zero value was used in statistical analysis); DM, dry matter.

^a-dMeans within the same rows with different superscripts are significantly different at P<0.05.

Table 2. Chemical composition and in vitro dry matter digestibility of oil palm frond before and after an ensiling period of 12 weeks.

	Before ensiling	Experimental silages				SEM	P
		No additive	LAB	Cellulase	LAB+cellulase
DM, g/kg	448	389	385	375	374	4.88	0.653
Digestibility, %	50.0	50.5^b	52.0^ab	54.0^a	55.1^a	1.01	0.031
Ash, g/kg DM	68.1	72.4	75.3	75.1	75.9	1.85	0.659
CP, g/kg DM	43.5	44.6^b	47.8^a	47.8^a	51.0^a	0.92	0.031
EE, g/kg DM	31.4	27.3^b	28.5^ab	29.7^a	29.5^a	0.30	0.025
NDF, g/kg DM	741	729^a	726^a	693^b	674^b	8.86	0.027
ADF, g/kg DM	517	503^a	494^ab	460^b	456^b	6.55	0.007
Cellulose, g/kg DM	335	328^a	315^a	294^ab	284^b	6.61	0.034
Hemicellulose, g/kg DM	223	226	232	233	218	10.6	0.813
ADL, g/kg DM	182	175	179	166	172	2.54	0.325

LAB, lactic acid bacteria; DM, dry matter; CP, crude protein; EE, ether extract; NDF, neutral detergent fibre; ADF, acid detergent fibre; cellulose, ADF-ADL; hemicellulose, NDF-ADF; ADL, acid detergent lignin.

^a,bMeans within the same rows with different superscripts are significantly different at P<0.05.

Table 3. Total fatty acid content (mg/g DM) and fatty acid composition (g/100 g of total identified fatty acids) of oil palm frond before and after ensiling for 12 weeks.

	Before ensiling	Experimental silages				SEM	P
		No additive	LAB	Cellulase	LAB+cellulase
TFA	36.70	31.44	32.58	31.61	30.69	0.21	0.193
C12:0	1.97	2.36	2.56	2.52	2.65	0.05	0.281
C.14:0	3.97	3.40	3.66	3.73	3.65	0.06	0.186
C15:0	0.62	0.21	0.39	0.38	0.32	0.03	0.061
C15:1	3.44	1.73	2.53	2.26	2.38	0.09	0.864
C16:0	35.14	35.80	35.19	35.48	34.93	0.35	0.061
C16:1	0.90	1.24	1.21	1.54	1.52	0.06	0.140
C17:0	2.10	2.46	2.69	2.51	2.74	0.08	0.531
C17:1	0.62	0.57	0.54	0.50	0.51	0.02	0.734
C18:0	7.44	6.11	5.93	6.27	6.01	0.25	0.061
C18:1n-9	6.58	8.98^a	7.98^b	8.33^ab	7.80^b	0.16	0.034
C18l:1trans-11	0.00	0.36^b	2.10a	1.75a	2.15a	0.20	0.001
C18:2n-6	12.76	12.44	12.23	12.61	12.49	0.28	0.975
C18:3n-3	24.47	22.36	22.98	22.12	22.83	0.29	0.738
Total SFA^°	51.23	52.33	50.43	50.89	50.31	0.33	0.101
Total MUFA^#	11.54	12.88^b	14.36^a	14.39^a	14.37^a	0.33	0.034
Total n-3PUFA^§	24.47	22.36	22.98	22.12	22.83	0.24	0.738
Total n-6PUFA^∧	12.76	12.44	12.23	12.61	12.49	0.29	0.975
n-6:n-3^$	0.52	0.56	0.53	0.57	0.55	0.02	0.912
UFA:SFA	0.95	0.91	0.98	0.97	0.99	0.01	0.116
PUFA:SFA	0.73	0.67	0.70	0.68	0.70	0.01	0.116

LAB, lactic acid bacteria; TFA, total fatty acids; SFA, saturated fatty acids; MUFA, monounsaturated fatty acids; PUFA, polyunsaturated fatty acids; UFA, unsaturated fatty acids.

°Total SFA, sum of C12:0, C14:0, C15:0, C16:0, C17:0, C18:0

^#total MUFA, sum of C15:1, C16:1, C17:1, C18:1n-9

^§total n-3PUFA, C18:3n-3

∧total n-6PUFA, C18:2n-6

^$n-6: n-3, total PUFA n-6 (C18:2n-6):total PUFA n-3 (C18:3n-3).

^a,bMeans within the same rows with different superscripts are significantly different at P<0.05.