Grass/clover silage for growing/finishing pigs – effect of silage pre-treatment and feeding strategy on growth performance and carcass traits

Figures & data

Table 1. Ingredient composition (% of ingredients per kg feed), estimated energy content (MJ kg⁻¹ DM) and crude protein content (g kg⁻¹ DM) of the control feed, the silage pellet feed (SP) and the basal feed for the total mixed ration (TMR) diets.

	Control feed	SP feed	Basal feed
Wheat	43	51.83	30
Barley	25.53	–	–
Rye	–	–	12.69
Field beans	13.38	20.3	20
Peas	–	–	10
Rapeseed meal	12	–	–
Rapeseed	–	–	7.96
Soybean meal	0.95	–	–
Potato protein	–	4.37	5.2
Maize meal	–	–	10
Silage pellet	–	20	–
Limestone	1.11	0.89	0.6
Premix finishing pigs	0.12	0.12	0.22
Estimated energy and crude protein content
Dry matter, %	87	88	87
Net energy	10.8	10	12.2
Crude protein	184	198	207

Table 2. Chemical composition (g kg⁻¹ DM), energy content (MJ kg⁻¹ DM) and amino acid content (% feed) of the control feed, the silage pellet (SP) feed, the basal feed for the total mixed ration (TMR) and the chopped (SC) and intensively treated (SE) silage, and TMR as fed (SC and SE). TMR as fed represents the composition in a 40:60 ratio of silage and basal feed.

	Control feed	SP feed^a	Basal feed^b	Chopped silage, SC	Intensively treated silage, SE	TMR as fed SC	TMR as fed SE
Dry matter, %	88	89	88	34	35	66	67
Gross energy	18.3	18.9	19.5	16.7	17.2	18.4	18.6
Net energy^c	11.0	11.0	11.8	8.1	8.9	10.3	10.6
Crude protein	191	202	205	183	178	196	194
Crude fat	36	51	69	–	–	41	41
Ash	51	59	42	95	97	63	64
Neutral detergent fibre	126	157	117	384	361	224	215
Lysine	0.945	0.890	1.02	0.727	0.690	0.903	0.888
Methonine	0.270	0.247	0.282	0.288	0.269	0.284	0.277
Threonine	0.629	0.713	0.765	0.720	0.684	0.747	0.733
Valine	0.742	0.846	0.857	0.880	0.895	0.866	0.872

^a Commercial feed + ground silage, mixed and pelleted.

^b Basal feed optimised for mixing with silage in a TMR.

^c Estimated according to Lindberg and Andersson (1998), where energy digestibility (dE%) = 94.8 + (− 0.93 × NDF %). Digestible energy (DE) = dE × GE, ME = 0.95 × DE and NE = 0.75 × ME.

Table 3. Chemical composition and hygiene quality of fresh silage used in the chopped (SC) and intensively treated (SE) silage diets, and of the same silage after one week of storage at 4°C.

	Fresh silage	Silage stored for 1 week
Dry matter %	35	34
Crude protein (CP, g kg^−1 DM)	183	184
Gross energy (GE, MJ kg^−1 DM)	16.7	17.4
Water-soluble carbohydrates (g kg^−1 DM)	118	122
pH	4.22	4.15
Fermentation products, % of dry matter
Lactic acid	4.7	4.8
Formic acid	1.2	1.2
Acetic acid	0.8	0.9
Propionic acid	0.2	0.2
Butyric acid	< 0.02	<0.02
2,3-butandiol	0.04	0.06
Ethanol	0.1	0.1
Ammonia-nitrogen	3.3	3.4
(% of total nitrogen)

Table 4. Difference in daily average feed (kg), energy (MJ NE) and protein (g CP) intake between diets (SP = pellet with silage inclusion, SC = Basal feed + chopped silage fed as TMR, SE = Basal feed + intensively treated silage fed as TMR) and effect of diet on feed- and protein conversion ratio (MJ NE kg⁻¹ growth and g CP kg⁻¹ growth), presented for growing phase 1, 2 and all phases. The results are presented as least square means and pooled standard error (SEM). Level of significance was set at P < 0.05.

	Control (N = 32)	SP (N = 30)	SC (N = 31)	SE (N = 31)	SEM	P^#
Phase 1 30–65 kg
Days in phase 1	28.5	28.5	28.5	28.5	0.02	0.42
Feed intake	2.52^a	2.78^a	3.35^b	3.35^b	0.06	0.001
Energy intake	24.4^a	27.2^b	23.1^a	23.8^a	0.85	0.003
Protein intake	423.1^a	499.6^b	436.3^a	434.3^a	11.02	0.002
Feed conversion ratio	25.6	28.2	28.6	26.8	0.93	0.15
Protein conversion ratio	443.7^a	517.4^b	540.2^b	490.4^ab	17	0.01
Phase 2 65–110 kg
Days in phase 2	51.7^ab	50.2^b	55.3^a	53.4^ab	1.53	0.01
Feed intake	2.40^a	2.53^a	3.22^b	3.22^b	0.05	0.001
Energy intake	23.4^ab	24.8^b	22.2^a	22.9^ab	0.49	0.02
Protein intake	403.2^a	455.4^b	420.1^ab	417.8^ab	9.04	0.01
Feed conversion ratio	21.9	21.7	21.7	21.7	0.48	0.99
Protein conversion ratio	379.2	397.6	410.6	396.5	8.83	0.15
All phases 30–110 kg
Total days in study	80.2^ab	78.7^a	83.8^b	81.9^ab	1.53	0.01
Feed intake	2.43^a	2.61^a	3.25^b	3.25^b	0.02	0.001
Energy intake	23.6^a	25.6^c	22.4^b	23.1^ab	0.17	0.001
Protein intake	408.2^b	469.8^c	423.8^a	421.1^ab	3.03	0.001
Feed conversion ratio	23.0	23.6	23.6	23.1	0.23	0.145
Protein conversion ratio	398.7^c	433.8^ab	446^b	421.8^a	4.23	0.001

#Probability: Different superscript letters within rows indicate pairwise differences at P < 0.05.

Table 5. Effect of sex and effect of diet (SP = pellet with silage inclusion, SC = Basal feed + chopped silage fed as TMR, SE = Basal feed + intensively treated silage fed as TMR) on weight gain and carcass traits. The results are presented as least square means and pooled standard error (SEM). Level of significance was set at P < 0.05.

	Diet				Sex^†
	Control (N = 32)	SP (N = 30)	SC (N = 31)	SE (N = 31)	SEM	P^#	m	f	SEM	P^#
Initial weight (kg)	32.7	32.4	32.8	32.5	0.74	0.95	32.9	32.2	0.7	0.217
Final weight (kg)	114.7^ab	117.7^b	111.5^a	113.4^ab	1.5	0.014	116.6	112.1	1.02	0.001
Daily weight gain 30–65 kg (g)	952^bc	966^c	811^a	887^ab	24.4	0.001	905	904	14	0.956
Daily weight gain 65–110 kg (g)	1064^a	1148^b	1022^a	1054^a	19	0.001	1141	1003	17	0.001
Daily weight gain 30–110 kg (g)	1023^a	1084^b	951^c	996^a	14.8	0.001	1056	971	11.6	0.001
Carcass weight (kg)	84.6^bc	85.3^b	81.1^ac	82.5^ab	1.1	0.018	83.8	82.9	0.95	0.183
Dressing percentage (%)	73.8^c	72.8^bc	72.5^ab	72.7^ab	0.41	0.016	72.2	73.7	0.32	0.001
Lean meat content (%)	60.7	60.8	61.5	60.9	0.5	0.832	60.0	61.8	0.26	0.001
Lean meat growth 30–110 (g day^−1)	465.5^b	481.0^b	422.2^a	442.2^a	8.1	0.001	0.460	0.446	0.01	0.01

N = number of pigs in each treatment diet group.

†m = castrated male (immunocastrated with Improvac™), f = gilt.

#Probability: Different superscript letters within rows indicate pairwise differences at P < 0.05.

Lindberg, J. E. & Andersson, C. (1998). The nutritive value of barley-based diets with forage meal inclusion for growing pigs based on total tract digestibility and nitrogen utilization. Livestock Production Science, 56(1), 43–52. doi:10.1016/S0301-6226(98)00146-8

 Google Scholar