The Effect of Slaughter Weight and Fattening Intensity on Changes in Carcass Fatness in Young Holstein-Friesian Bulls

Figures & data

Figure 1. Effect of fattening intensity and body weight at slaughter on dressing percentage.

Figure 2. Effect of fattening intensity and body weight at slaughter on carcass conformation.

Figure 3. Effect of fattening intensity and body weight at slaughter on carcass fatness score.

Figure 4. Effect of fattening intensity and body weight at slaughter on back fat thickness.

Figure 5. Effect of fattening intensity and body weight at slaughter on the fat content of m. longissimus dorsi.

Figure 6. Effect of fattening intensity and body weight at slaughter on the n-6/n-3 PUFA ratio.

Table 1. Chemical composition and nutritional value ingredients of experimental diets (mean±SD).

Specification	Silage (n=9)	Triticale (n=1)	Rapeseed meal (n=1)	Concentrate I (n=7)	Concentrate II (n=7)
Dry Matter, g/kg	397.00±109.30	881.00	887	883.90±7.10	885.50±8.20
Organic matter, g/kg DM	920.00±30.60	981.00	927.00	932±13.10	925±18.30
Crude protein, g/kg DM	141.00±11.40	133.00	388.00	189±15.10	163±7.10
NDF, g/kg DM	569.00±52.30	193.00	310.00	202±11.20	184±7.90
ADF, g/kg DM	387.00±59.20	44.00	228.00	72±5.80	31±8.20
DOMD, g/kg DM	741.00±55.90	932.00±26.50	848.00±4.40	-	-
UFV, g/kg DM	0.80±0.03	1.21	1.01	1.18±0.03	1.21±0.02
PDIN, g/kg DM	82.20±6.64	89.00	259.00	122.2±2.40	112.40±5.20
PDIE^°, g/kg DM	69.50±2.28	109.00	163.00	129.6±5.20	121.10±4.70

DM, dry matter; NDF, neutral detergent fiber; ADF, acid detergent fiber; DOMD, digestible organic matter in DM repeated 3 times; UFV, meat fodder units; PDIN, protein digested in the small intestine when rumen fermentable N is limiting; PDIE, protein digested in the small intestine when rumen fermentable energy is limiting.

°Fermentation characteristics of silage: pH 4.8±0.3; lactic acid, 54±20.4 g/kg DM; volatile fatty acids, 27±5.3 g/kg DM; water soluble carbohydrates, 82±47.6 g/kg DM; N-NH3, 103±67.4 g/kg N; true protein, 518±45.6 g/kg crude protein.

Table 2. Chemical composition and nutritional value of total mixed ration.

Specification	SI<300 kg BW	I< 300 kg BW	SI>300 kg BW	I>300 kg BW
Grass silage, %	75.00^°	60.00^°	75.00^°	60.00^°
Concentrate I, %	25.00	40.00	-	-
Concentrate II, %	-	-	25.00	40.00
DM, g/kg DM	518.50	591.40	519.00	592.20
Crude protein, g/kg DM	153.00	160.00	146.00	150.00
NDF, g/kg DM	473.00	415.00	466.00	405.00
ADF, g/kg DM	308.00	184.00	298.00	167.00
UFV, g/kg DM	0.900	0.96	0.91	0.97
PDIN, g/kg DM	92.20	98.20	89.80	94.30
PDIE, g/kg DM	83.50	93.50	82.40	91.10

SI, semi-intensive fattening; BW, body weight; I, intensive fattening; DM, dry matter; NDF, neutral detergent fiber; ADF, acid detergent fiber; UFV, meat fodder units; PDIN, protein digested in the small intestine when rumen fermentable N is limiting; PDIE, protein digested in the small intestine when rumen fermentable energy is limiting.

°Ratios=75:25 in dry and 87:13 in fresh matter; 60:40 in dry and 77:23 in fresh matter.

Table 3. Average age at slaughter and selected traits of intensively and semi-intensively fattened Holstein-Friesian bulls.

Traits	SI fattening (n=50)		I fattening (n=50)		Significance
	Mean	SEM	Mean	SEM
At beginning of fattening
Average age, d	103.00	0.22	98.00	0.32	ns
Average weight, kg	121.00	0.12	124.00	0.21	ns
At slaughter
Average age, d	696.00	0.24	552.00	0.26	^**
Average weight at slaughter, kg	603.00	7.71	611.00	7.42	ns
Average daily gain, kg d^–1	0.811	0.0113	1.037	0.0131	^**
Dressing percentage, %	54.24	0.263	55.41	0.211	^*
Conformation score, pts^°	5.50	0.15	6.50	0.13	^**
Fatness score, pts^#	3.50	0.14	4.50	0.13	^**
BFT, mm	4.40	0.27	5.30	0.26	^*
Intramuscular fat, %	1.18	0.166	1.69	0.248	^*

SI, semi-intensive; I, intensive fattening; BFT, back fat thickness.

°EUROP conformation: 1 to 15, with 1=very lean, and 15=muscled outstanding

#EUROP degree of fat cover: 1 to 15, with 1=very low, and 15=very fat.

*P≤0.05

**P≤0.01; ns, not significant (P>0.05).

Table 4. The effect of fattening intensity on fatty acid groups and ratios in intramuscular fat.

Fatty acid of total fatty acids, g/100 g	SI fattening		I fattening		Significance
	Mean	SEM	Mean	SEM
SFA	49.42	1.706	48.90	0.868	ns
UFA	50.58	1.711	51.10	0.851	ns
MUFA	45.91	1.626	47.39	0.887	ns
PUFA	4.67	0.487	3.71	0.211	^*
UFA/SFA	1.05	0.071	1.06	0.036	ns
PUFA/SFA	0.097	0.011	0.076	0.005	^*
n-3	0.741	0.108	0.551	0.048	ns
n-6	3.18	0.289	2.56	0.162	^*
n-6/n-3	4.29	0.272	4.64	0.395	ns

SI, semi-intensive; I, intensive fattening; SFA, saturated fatty acid; UFA, unsaturated fatty acid; MUFA, monounsaturated fatty acid; PUFA, polyunsaturated fatty acid.

*P≤0.05; ns, not significant (P>0.05).

Table 5. The effect of fattening intensity on functional fatty acids in intramuscular fat.

Fatty acid of total fatty acids, g/100 g	SI fattening		I fattening		Significance
	Mean	SEM	Mean	SEM
C 18:1 trans 11 (TVA)	1.153	0.163	1.051	0.095	ns
C 18:1 cis (OA)	37.84	1.441	38.79	0.686	ns
C 18:2 (LA)	2.72	0.197	2.17	0.125	^*
C 18:2 cis 9 trans 11 (CLA)	0.217	0.034	0.241	0.015	ns
C 18:3 (LNA)	0.647	0.085	0.516	0.041	ns
C 20:4 (AA)	0.456	0.097	0.288	0.051	^*
C 20:5 (EPA)	0.094	0.025	0.056	0.011	ns
C 22:5 (DPA)	0.223	0.052	0.154	0.024	ns

SI, semi-intensive; I, intensive fattening; TVA, trans-vaccenic acid; OA, oleic acid; LA, linoleic acid; CLA, conjugated linoleic acid; LNA, linolenic acid; AA, arachidonic acid; EPA, eicosapentaenoic acid; DPA, docosapentaenoic acid.

*P≤0.05; ns, not significant (P>0.05).