Effects of inoculant application on fermentation quality and rumen digestibility of high moisture sorghum-sudangrass silage

Figures & data

Table 1. Chemical compositions and in vitro digestibility of sorghum-sudangrass forages before ensiling (%, DM).

Item	SX^a	SU
Dry matter	22.8	23.3
Crude protein	11.8	11.2
Ether extract	2.80	3.41
Crude ash	8.64	9.13
Neutral detergent fibre	67.3	67.5
Acid detergent fibre	37.3	37.9
IVDMD^b	57.4	58.4
IVNDFD	52.9	53.8

^aSX, SX-17 sorghum-sudangrass hybrid; SU, Speed-up sorghum-sudangrass hybrid.

^bIVDMD, in vitro dry matter digestibility; IVNDFD, in vitro neutral detergent fibre digestibility.

Table 2. Effects of new inoculant on the chemical composition of high moisture sorghum-sudangrass silages ensiled for 60 days (%, DM).

Item	SX^a		SU		SEM	Contrast^b
	CON	INO	CON	INO		H	I	H*I
Dry matter	17.2	18.5	18.6	20.9	0.819	0.002	0.002	0.323
Crude protein	11.5	12.5	11.3	12.4	0.176	0.057	<.001	0.327
Ether extract	2.50	2.66	3.03	3.51	0.340	0.002	0.084	0.373
Crude ash	9.14	9.08	9.52	10.0	0.385	0.006	0.302	0.182
Neutral detergent fibre	68.3	68.6	68.6	68.9	0.121	0.020	0.010	0.822
Acid detergent fibre	39.5	40.4	38.6	39.7	0.879	0.112	0.046	0.863

^aSX, SX-17 sorghum-sudangrass hybrid; SU, Speed-up sorghum-sudangrass hybrid; CON, silage treated without inoculant; INO, silage inoculated with a combination of Lactobacillus plantarum R48-27 and Lactobacillus buchneri R4-26 at 2 × 10⁵ of fresh forage.

^bH, hybrid effect; I, inoculant effect; H*I, interaction between hybrid and inoculant effect.

Table 3. Effect of new inoculant on fermentation indices and microbial counts of high moisture sorghum-sudangrass silages ensiled for 60 days.

Item	SX^a		SU		SEM	Contrast^b
	CON	INO	CON	INO		H	I	H*I
Fermentation indices
pH	4.32	4.44	4.25	4.37	0.026	0.001	<.001	0.769
Ammonia-N, % of DM	0.08	0.07	0.07	0.06	0.009	0.044	0.044	0.585
Lactate, % of DM	2.08	1.81	1.89	1.81	0.098	0.183	0.045	0.182
Acetate, % of DM	0.69	0.81	0.68	1.01	0.069	0.054	0.001	0.032
Butyrate, % of DM	0.89	0.73	0.81	0.76	0.073	0.540	0.047	0.298
Lactate: Acetate ratio	3.01	2.22	2.78	1.79	0.085	0.054	<.001	0.518
Microbial counts, log10 cfu/g
Lactic acid bacteria	7.81	7.91	7.82	7.94	0.017	0.732	0.112	0.909
Yeast	7.48	7.65	7.59	7.71	0.107	0.161	0.025	0.649
Mold	ND^c	ND	ND	ND	–	–	–	–

^aSX, SX-17 sorghum-sudangrass hybrid; SU, Speed-up sorghum-sudangrass hybrid; CON, silage treated without inoculant; INO, silage inoculated with a combination of Lactobacillus plantarum R48-27 and Lactobacillus buchneri R4-26 at 2 × 10⁵ of fresh forage.

^bH, hybrid effect; I, inoculant effect; H*I, interaction between hybrid and inoculant effect.

^cNot detected.

Table 4. Effect of new inoculant on yeast and mold count of high moisture sorghum-sudangrass silages during aerobic exposure (log₁₀ cfu/g).

Item	Aerobic days	SX^a		SU		SEM	Contrast^b
		CON	INO	CON	INO		H	I	H*I
Yeast	1	7.48	7.66	7.61	7.74	0.110	0.070	0.015	0.659
	2	7.74	7.69	7.62	7.74	0.105	0.565	0.915	0.244
	3	7.83	7.76	7.79	7.74	0.108	0.647	0.263	0.902
	4	7.92	7.81	7.89	7.76	0.100	0.613	0.044	0.913
	6	7.96	7.82	8.02	7.79	0.107	0.827	0.010	0.409
	8	7.97	7.94	8.03	7.82	0.045	0.039	0.002	0.010
Mold	1	ND^c	ND	ND	ND	–	–	–	–
	2	ND	ND	ND	ND	–	–	–	–
	3	ND	ND	ND	ND	–	–	–	–
	4	ND	ND	ND	ND	–	–	–	–
	6	ND	ND	ND	ND	–	–	–	–
	8	ND	ND	ND	ND	–	–	–	–

^aSX, SX-17 sorghum-sudangrass hybrid; SU, Speed-up sorghum-sudangrass hybrid; CON, silage treated without inoculant; INO, silage inoculated with a combination of Lactobacillus plantarum R48-27 and Lactobacillus buchneri R4-26 at 2 × 10⁵ of fresh forage.

^bH, hybrid effect; I, inoculant effect; H*I, interaction between hybrid and inoculant effect.

^cNot detected

Table 5. Effect of new inoculant on in vitro rumen digestibility and fermentation characteristic of high moisture sorghum-sudangrass silages after incubated for 72 h.

Item	SX^a		SU		SEM	Contrast^b
	CON	INO	CON	INO		H	I	H*I
IVDMD^c, % of DM	49.3	52.6	54.4	57.3	1.355	<.001	0.003	0.772
IVNDFD, % of DM	56.4	56.8	57.0	58.0	0.754	0.065	0.147	0.553
pH	6.27	6.42	6.28	6.35	0.031	0.055	<.001	0.056
Ammonia-N, mg/dL	33.8	43.9	29.8	35.2	3.472	0.001	0.003	0.484
Total VFA, mM/L	73.8	73.8	74.4	73.9	1.801	0.709	0.835	0.831
Acetate, % of molar	53.8	54.8	54.1	54.8	0.574	0.697	0.014	0.599
Propionate, % of molar	23.9	22.8	23.4	22.7	0.633	0.463	0.015	0.512
Iso-butyrate, % of molar	1.98	1.97	2.04	2.03	0.065	0.113	0.769	0.943
Butyrate, % of molar	12.3	11.8	12.4	12.0	0.435	0.456	0.082	0.831
Iso-valerate, % of molar	4.95	5.2	4.83	5.12	0.260	0.380	0.075	0.902
Valerate, % of molar	3.06	3.42	3.22	3.32	0.156	0.808	0.012	0.136
Acetate: Propionate ratio	2.25	2.41	2.31	2.41	0.081	0.600	0.009	0.528

^aSX, SX-17 sorghum-sudangrass hybrid; SU, Speed-up sorghum-sudangrass hybrid; CON, silage treated without inoculant; INO, silage inoculated with a combination of Lactobacillus plantarum R48-27 and Lactobacillus buchneri R4-26 at 2 × 10⁵ of fresh forage.

^bH, hybrid effect; I, inoculant effect; H*I, interaction between hybrid and inoculant effect.

^cIVDMD, in vitro dry matter digestibility; IVNDFD, in vitro neutral detergent fibre digestibility.