Effect of Dietary Energy and Protein on the Performance, Egg Quality, Bone Mineral Density, Blood Properties and Yolk Fatty Acid Composition of Organic Laying Hens

Figures & data

Table 1. Experimental diet composition.

	2750 kcal/kg ME		2775 kcal/kg ME		2800 kcal/kg ME
	16% CP	17% CP	16% CP	17% CP	16% CP	17% CP
Ingredients, %
Corn	66.08	63.98	66.64	64.56	67.23	65.14
Soybean meal	21.13	21.64	19.24	19.79	17.38	17.93
Corn gluten meal	1.74	3.32	3.01	4.55	4.24	5.78
Limestone	9.44	9.42	9.42	9.42	9.42	9.42
Calcium phosphate	0.87	0.89	0.92	0.91	0.94	0.92
Salt	0.37	0.38	0.38	0.38	0.38	0.38
L-Lysine	-	-	0.02	0.03	0.05	0.07
DL-Methionine	0.04	0.04	0.04	0.03	0.03	0.03
Vitamin premix^°	0.18	0.18	0.18	0.18	0.18	0.18
Mineral premix^#	0.15	0.15	0.15	0.15	0.15	0.15
Calculated composition
ME, kcal/kg	2750	2750	2775	2775	2800	2800
CP, %	16	17	16	17	16	17
Lysine, %	0.74	0.78	0.74	0.78	0.74	0.78
Methionine, %	0.32	0.34	0.32	0.34	0.32	0.34
Calcium, %	3.75	3.75	3.75	3.75	3.75	3.75
Sodium, %	0.17	0.17	0.17	0.17	0.17	0.17
Available phosphate, %	0.27	0.27	0.27	0.27	0.27	0.27

°Contain per kg: retinol, 3.6 mg; cholecalciferol, 0.125 mg; tocopherol, 50 mg; menadione, 3 mg; thiamine, 2 mg; riboflavin, 6 mg; pyridoxine, 4 mg; cyanocobalamin, 0.025 mg; biotin, 0.15 mg; pantothenicacid, 20 mg; folic acid, 2 mg; nicotinicacid, 7 mg.

^#Contain per kg: Fe, 66,720 mg; Cu, 41,700 mg; Mn, 83,400 mg; Zn, 66,72 mg; I, 834 mg; Se, 250 mg. ME, metabolizable energy; CP, crude protein.

Table 2. Effect of various levels of organic dietary metabolizable energy and crude protein on the performance in laying hens from 23 to 46 weeks.

	Treatments
	2750 kcal/kg ME		2775 kcal/kg ME		2800 kcal/kg ME		P value
	16% CP	17% CP	16% CP	17% CP	16% CP	17% CP	ME×CP
Egg production, %	93.74±1.8	90.99±1.5	92.01±1.3	90.66±2.8	91.18±3.3	92.09±2.5	0.3085
Egg weight, g	61.48±0.8^b	62.15±0.9^a	62.41±0.5^a	61.85±0.5^ab	61.28±0.5^b	62.48±0.6^a	0.0448
Egg mass	57.64±1.6	56.49±1.5	57.42±0.6	56.15±1.6	55.91±1.9	56.84±2.5	0.3760
Feed intake, g/d	145.06±2.9	145.73±5.1	143.85±0.5	143.71±0.6	145.05±3.4	147.63±5.5	0.7415
FCR	2.517±0.1	2.581±0.1	2.505±0.02	2.560±0.1	2.595±0.1	2.599±0.1	0.7697

Values are mean±SE. ME, metabolizable energy; CP, crude protein; FCR, feed conversion ratio.

^a,bValues with the same letters are not significantly different at 5% level.

Table 3. Effect of various levels of organic dietary metabolizable energy and crude protein on blood composition in laying hens.

	Treatments
	2750 kcal/kg ME		2775 kcal/kg ME		2800 kcal/kg ME		P value
16% CP	17% CP	16% CP	17% CP	16% CP	17% CP	ME×CP
TPN, g/dL	5.19±0.5	6.00±0.8	5.05±0.4	5.26±0.5	5.38±0.5	5.38±0.5	0.0557
ALB, g/dL	1.28±0.1	1.38±0.1	1.26±0.1	1.39±0.3	1.34±0.2	1.28±0.1	0.2012
TCL, mg/dL	115.9±47.9	113.6±31.8	101.0±35.1	93.9±14.7	121.3±43.3	93.9±19.8	0.4733
TG, mg/dL	1204.7±247.3	1114.7±216.4	1010.4±228.8	850.4±235.3	1245.4±211.6	855.3±188.9	0.6444
HDL, mg/dL	37.8±7.9	37.9±4.6	37.4±4.2	37.2±6.1	36.8±4.2	35.3±5.7	0.8932

Values are mean±SE. ME, metabolizable energy; CP, crude protein; TPN, total protein; ALB, albumin; TCL, total cholesterol; TG, triacylglyceride; HDL, high density lipoprotein.

Table 4. Effects of various levels of organic dietary metabolizable energy and crude protein on the bone mineral density (BMD) and bone breaking strength in laying hens.

	Treatments
	2750 kcal/kg ME		2775 kcal/kg ME		2800 kcal/kg ME		P value
	16% CP	17% CP	16% CP	17% CP	16% CP	17% CP	ME×CP
BMD, g/cm^2	0.249±0.01	0.222±0.01	0.271±0.04	0.265±0.02	0.231±0.02	0.217±0.01	0.6345
BBS, kg	21.05±0.39	21.49±0.14	28.50±0.68	25.28±0.22	22.82±0.41	20.55±0.42	0.5989

Values are mean±SE. BMD, bone mineral density; BBS, bone breaking strength.

Table 5. Effects of various feeding organic dietary metabolizable energy and crude protein on egg quality in laying hens.

	Treatments
	2750 kcal/kg ME		2775 kcal/kg ME		2800 kcal/kg ME		P value
	16% CP	17% CP	16% CP	17% CP	16% CP	17% CP	ME×CP
ESC	28.70±4.3	27.03±3.4	27.33±4.3	27.60±4.7	27.23±3.9	25.96±4.7	0.4234
ESBS, kg/cm^2	4.83±1.1	4.58±0.9	4.39±0.9	5.03±1.2	4.58±1.4	4.63±1.1	0.0793
AH, mm	7.08±1.1	6.81±1.1	7.40±1.1	7.39±1.2	7.12±1.0	7.15±1.2	0.7264
HU	82.12±7.6	79.17±7.8	83.59±6.4	83.40±7.2	82.41±6.7	81.92±8.8	0.5409
YC	8.40±0.6	8.50±0.6	8.86±0.7	9.06±0.4	8.83±0.6	9.06±0.5	0.8056

Values are mean±SE. ESC, egg shell color; ESBS=egg shell breaking strength; AH, albumin height; HU, Haugh unit; YC, yolk color.

Table 6. Effects of various feeding organic dietary metabolizable energy and crude protein on fatty acid composition of egg yolk.

	Treatments
	2750 kcal/kg ME		2775 kcal/kg ME		2800 kcal/kg ME		P value
	16% CP	17% CP	16% CP	17% CP	16% CP	17% CP	ME×CP
C14:0	0.29±0.02	0.27±0.0	0.26±0.0	0.31±0.0	0.29±0.0	0.29±0.0	0.07
C16:0	26.15±0.2	26.13±1.4	25.16±0.7	25.57±0.7	24.94±0.7	25.03±0.7	0.83
C16:1n7	2.55±0.4	2.49±0.5	2.43±0.5	2.63±0.6	2.73±0.5	2.25±0.4	0.33
C18:0	11.90±0.6	11.28±0.3	11.74±0.9	10.85±0.8	10.83±0.3	10.98±0.3	0.16
C18:1n9	38.78±1.4	38.62±1.2	40.02±2.4	40.16±1.6	39.58±2.0	40.56±0.9	0.74
C18:2n6	15.49±1.4	16.00±2.7	15.51±1.6	15.92±1.2	16.87±1.9	16.49±0.6	0.82
C18:3n3	0.50±0.2	0.55±0.1	0.38±0.0	0.44±0.1	0.48±0.1	0.46±0.1	0.71
C20:4n6	3.13±0.0	3.15±0.1	3.17±0.2	2.99±0.5	3.08±0.1	2.74±0.4	0.38
C20:6n3	1.21±0.23^b	1.47±0.0^a	1.29±0.1^ab	1.10±0.2^b	1.16±0.2^b	1.15±0.1^b	0.02

Values are mean±SE.

^a,bValue with the same letters are not significantly different at 5% level.

Table 7. Effects of various feeding organic dietary metabolizable energy and crude protein on fatty acid composition of egg yolk.

	Treatments
	2750 kcal/kg ME		2775 kcal/kg ME		2800 kcal/kg ME		P value
	16% CP	17% CP	16% CP	17% CP	16% CP	17% CP	ME×CP
SFA	38.35±0.4	37.69±1.4	37.17±1.5	36.73±1.1	36.07±0.9	36.30±0.7	0.63
UFA	61.64±0.4	62.30±1.4	62.82±1.5	63.26±1.1	63.92±0.9	63.69±0.7	0.63
MUFA	41.29±1.5	41.11±1.5	42.45±2.8	42.80±1.8	42.31±1.9	42.82±0.6	0.91
PUFA	20.34±1.5	21.18±2.6	20.36±1.7	20.45±1.1	21.60±2.0	20.86±0.7	0.59
UFA/SFA	1.60±0.0	1.65±0.1	1.69±0.1	1.72±0.1	1.77±0.1	1.75±0.0	0.63
n-3	1.71±0.3	2.03±0.1	1.67±0.1	1.54±0.3	1.64±0.2	1.62±0.1	0.07
n-6	18.63±1.4	19.15±2.6	18.69±1.6	18.91±1.1	19.96±1.8	19.24±0.7	0.68
n-6/n-3	11.12±2.1	9.48±1.6	11.17±0.6	12.54±2.3	12.28±1.6	11.90±0.9	0.14

SFA, saturated fatty acids were calculated as C₁₄:0+C₁₆:0+C₁₈:0; UFA, unsaturated fatty acids were calculated as C₁₆:1n7+C₁₈:1n9+C₁₈:2n6+C₁₈:3n3+C₂₀:4n6+C₂₂:6n3; MUFA, mono-unsaturated fatty acids were calculated as C₁₆:1n7+C₁₈:1n9; PUFA, poly-unsaturated fatty acids were calculated as C₁₈:2n6+ C₁₈:3n3+ C₂₀:4n6+ C₂₂:6n3; Total n-3 PUFA was calculated as C₁₈:3n3+ C₂₂:6n3; Total n-6 PUFA was calculated as C₁₈:2n6+ C₂₀:4n6; Ratio n-6/n-3 was calculated as total n-6 PUFA/total n-3 PUFA.