Influence of feed substitution with acorns on fattening performance, carcass characteristics, and meat composition of Prestice Black-Pied pigs finished in a conventional indoor system

Figures & data

Table 1. Nutrient composition of acorns

Dry matter	%	90.76
Crude protein	%	4.37
Ash	%	2.18
Saccharose	%	0.04
Starch	%	40.85
Ether extract	%	4.20
Fibre	%	9.82

Table 2. Ingredients and nutrient composition of mixed feeds

	Control mixture	Acorn mixture
Nutrients (%)
Dry matter	87.71	87.85
Crude protein	14.40	13.98
Ether extract	1.99	2.03
Crude fibre	4.65	5.39
Ash	5.03	4.95
ME (MJ/kg)	12.32	11.99
Ingredients (%)
Acorns	-	10
Wheat	25	25
Barley	54	50
Soybean meal (43%)	9	10
Wheat bran	9	2
Vitamin and mineral supplement	3	3
ATTD (%)
Crude protein	80.74	75.02
Ether extract	62.59	59.82
Crude fibre	54.25	45.00

Notes: ME—metabolizable energy, ATTD—apparent total tract digestibility.

Table 3. Performance parameters

	Control mixture		Acorn mixture
Parameter	Mean	SD	Mean	SD	Significance
Average live weight (kg)
At beginning of experiment	75.3	4.9	74.8	5.4	ns
At end of experiment	117.9	9.1	117.2	9.5	ns
Average daily gain (g/day)	761	87	750	81	ns
Average feed intake (kg/day)	3.08		3.17
Feed conversion ratio (kg/kg)	4.05		4.19

Significance levels: ns = not significant.

Table 4. Carcass traits and meat composition

	Control mixture		Acorn mixture
Trait	Mean	SD	Mean	SD	Significance
Lean meat content (%)	54.9	0.9	54.4	1.5	ns
Back fat thickness (mm)	22.3	3.4	25.0	2.1	ns
Drip loss (%)	2.6	0.5	2.9	0.9	ns
Component (determined in MLLT)
Dry matter (%)	27.43	0.85	25.94	0.16	*
Protein (%)	24.58	2.65	22.75	1.45	ns
Lipids (%)	4.43	1.36	5.29	0.26	ns

Notes: MLLT = musculus longissimus lumborum et thoracis.

Significance level: ns = not significant, * P < 0.05.

Table 5. Fatty acids profiles of acorns and mixed feeds (%)

Fatty acid	Acorns	Control mixture	Acorn mixture
C16:0	17.2	18.45	18.09
C18:0	4.13	9.82	9.63
C18:1n9	35.82	31.36	33.11
C18:2n6	29.27	20.42	20.59
C18:3n3	2.92	2.79	2.37
C20:4n6	0.23	0.78	0.82
∑SFAs	25.31	39.88	33.07
∑MUFAs	39.68	34.36	36.50
∑PUFAs	34.98	25.75	24.56
PUFA n-6/PUFA n-3 ratio		5.93	4.98

Table 6. Fatty acid profile of muscle (musculus longissimus lumborum et thoracis) (%)

Fatty acid	Control mixture		Acorn mixture
(%)	mean	SD	mean	SD	Significance
C14:0	1.40	0.11	1.23	0.14	ns
C15:1n-5	0.36	0.16	0.50	0.13	ns
C16:0	24.76	1.01	21.45	1.78	**
C16:1n-7	2.40	0.35	3.63	0.50	**
C17:0	0.49	0.09	0.30	0.03	**
C18:0	12.28	0.82	11.44	1.09	ns
C18:1n-9	39.65	1.42	42.69	2.21	***
C18:2n-6	9.54	0.79	9.89	0.53	ns
C18:3n-3	1.04	0.10	0.96	0.11	ns
C20:0	0.39	0.03	0.23	0.01	***
C20:1n-9	0.70	0.09	1.00	0.14	**
C20:2n-6	0.42	0.08	0.50	0.05	ns
C20:3n-6	0.17	0.07	0.42	0.05	***
C20:4n-6	1.02	0.14	1.48	0.13	**
C20:3n-3	0.24	0.09	0.42	0.07	*
∑ SFAs	43.06	1.22	36.26	0.58	***
∑ MUFAs	41.33	1.16	46.81	2.52	**
∑ PUFAs	13.81	0.85	12.93	1.20	ns
∑PUFA n-3	1.62	0.30	1.93	0.36	ns
∑PUFA n-6	11.31	1.00	12.38	0.62	ns
PUFA n-6/PUFA n-3 ratio	6.98		6.41
Atherogenic index	0,58		0,44
Thrombogenicity index	1,19		1,02

Notes: Significance level: ns = not significant, * P < 0.05, ** P < 0.01, *** P < 0.001.

Table 7. Fatty acid profile of back fat (%)

Fatty acid	Control mixture		Acorn mixture
(%)	mean	SD	mean	SD	Significance
C14:0	1.50	0.11	1.38	0.05	ns
C15:1n-5	0.04	0.02	0.09	0.01	**
C16:0	25.21	1.55	21.84	0.72	**
C16:1n-7	1.90	0.22	3.15	0.30	***
C17:0	0.40	0.02	0.32	0.03	**
C18:0	12.86	2.16	13.64	0.66	ns
C18:1n-9	37.88	1.45	41.24	2.05	**
C18:2n-6	12.19	1.44	12.97	0.82	ns
C18:3n-3	1.70	0.25	1.38	0.10	*
C20:0	0.23	0.04	0.16	0.03	*
C20:1n-9	0.78	0.12	1.06	0.09	**
C20:2n-6	0.65	0.07	0.55	0.06	ns
C20:3n-6	0.05	0.02	0.13	0.03	**
C20:4n-6	0.30	0.06	0.24	0.02	ns
C20:3n-3	0.19	0.04	0.29	0.04	**
∑SFAs	41.82	3.58	37.21	0.58	ns
∑MUFAs	41.70	1.46	45.38	2.18	*
∑PUFAs	15.60	0.86	15.30	1.81	ns
∑PUFA n-3	2.05	0.27	2.00	0.13	ns
∑PUFA n-6	13.25	1.55	13.91	0.78	ns
PUFA n-6/PUFA n-3 ratio	6.46		6.96
Atherogenic index	0.55		0.45
Thrombogenicity index	1.22		1.01

Notes: Significance level: ns = not significant, * P < 0.05, ** P < 0.01, *** P < 0.001.

Data availability statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.