Effect of dietary supplemental vitamin C and zinc sulfate on productive performance, egg quality traits and blood parameters of laying hens reared under cold stress condition

Figures & data

Table 1. Composition of the basal diet.

Ingredient	Amount (%)
Corn	67.64
Soybean meal	21.01
Wheat Bran	0.15
Soybean oil	0.07
Lime stone	3.00
Oyster Shells	5.47
Dicalcium phosphate	1.64
NaHCo3	0.18
Common salt	0.19
Min. Premix^a	0.25
Vit. Premix^b	0.25
DL-Methionine	0.15
Nutrient composition (as fed basis)
ME (Kcal/kg)	2750
Crude protein (%)	14.69
Calcium (%)	3.64
Available phosphorus (%)	0.37
Sodium (%)	0.15
Crude fibre (%)	2.32
(Na + K)-Cl (meg/kg)	207
Lysine (%)	0.71
Methionine (%)	0.37
Methionine + Cystine (%)	0.63
Threonine (%)	0.54
Tryptophan (%)	0.16
Zinc analysed (mg/kg)	36.8

^a Each 2.5 kg of mineral supplement contains: 33,000 mg iron, 66,000 mg zinc, 8800 mg copper, 6600 mg manganese, 900 mg iodine and 300 mg selenium.

^b Each 2.5 kg of vitamin supplement contains: 7,700,000 (IU) of vitamin A, 3,300,000 (IU) of vitamin D3, 6600 mg of vitamin E, 550 mg of vitamin K3, 2200 mg of vitamin B1, 4400 mg Vitamin B2, 4400 mg of vitamin B6, 5500 mg of calcium pentotonate, 2200 mg of niacin, 110 mg of folic acid, 275,000 mg of choline chloride, 125 mg of antioxidant, 55,000 μg of biotin and 8800 μg of B12.

Table 2. The effect of diet supplementation by vitamin C and Zn on feed intake (FI) and food conversion ratio (FCR) of the laying hens.

	FI (g/hen/day)				FCR (g/g)
Groups	Mon1	Mon2	Mon3	total	Mon1	Mon2	Mon3	total
Vitamin C (mg/kg)
0	119.81 ± 0.27	120 ± 0	120 ± 0	119.93 ± 0.09	2.47 ± 0.29	2.51 ± 0.35	2.40 ± 0.24	2.45 ± 0.24
240	119.83 ± 0.40	120 ± 0	120 ± 0	119.94 ± 0.13	2.37 ± 0.35	2.62 ± 0.50	2.38 ± 0.24	2.44 ± 0.30
Zn (mg/kg)
0	119.78 ± 0.78	120 ± 0	120 ± 0	119.92 ± 0.14	2.56 ± 0.27 a	2.75 ± 0.43 a	2.45 ± 0.26	2.58 ± 0.27 a
40	119.85 ± 0.20	120 ± 0	120 ± 0	119.95 ± 0.06	2.28 ± 0.32 b	2.38 ± 0.32 b	2.33 ± 0.18	2.31 ± 0.19 b
SEM	0.102	0	0	0.034	0.082	0.118	0.074	0.074
P value
Vitamin C	0.89	0	0	0.88	0.42	0.51	0.88	0.93
Zn	0.65	0	0	0.62	0.02	0.03	0.28	0.02
Vitamin C × Zn	0.70	0	0	0.72	0.02	0.23	0.68	0.17

Means ( ± SD) within columns with different lower case letters differ significantly (P ≤ 0.05).

SEM standard error of the mean for main effects.

Table 3. The effect of diet supplementation by vitamin C and Zn on egg weight (EW) and egg mass (EM) of the laying hens.

	EW (g)				EM (g/hen/day)
Groups	Mon1	Mon2	Mon3	total	Mon1	Mon2	Mon3	Total
Vitamin C (mg/kg)
0	66.99 ± 8.18	65.14 ± 1.77	65.05 ± 1.88	69.83 ± 3.73	49.13 ± 6.00	48.56 ± 6.61	50.36 ± 4.75	49.3 ± 34.82
240	69.371 ± 1.33	65.81 ± 3.04	65.70 ± 2.02	71.36 ± 4.49	51.40 ± 7.32	47.28 ± 8.85	50.72 ± 5.08	49.7 ± 16.08
Zn (mg/kg)
0	63.53 ± 7.93 ^b	64.89 ± 2.53	65.54 ± 2.44	67.34 ± 2.34 ^b	47.11 ± 4.96 ^b	44.63 ± 7.59 ^b	49.44 ± 5.38	46.9 ± 55.24 ^b
40	72.84 ± 9.63 ^a	66.06 ± 2.19	65.21 ± 1.16	73.86 ± 2.66 ^a	53.41 ± 7.06 ^a	51.21 ± 6.37 ^a	51.64 ± 3.89	52.0 ± 94.25 ^a
SEM	2.399	0.750	0.624	0.752	1.644	2.148	1.529	1.4 ± 61
P value
Vitamin C	0.49	0.53	0.46	0.16	0.34	0.67	0.86	0.85
Zn	0.01	0.28	0.71	0001. >	0.01	0.04	0.32	0.02
Vitamin C × Zn	0.01	0.44	0.82	0.42	0.02	0.18	0.73	0.13

Means ( ± SD) within columns with different lower case letters differ significantly (P ≤ 0.05).

SEM standard error of the mean for main effects.

Table 4. Comparison of mean interactions of vitamin C and Zn with egg weight (EW), egg mass (EM) and food conversion ratio (FCR) in the first month of laying hens.

Groups		EW (g)	EM (g/hen/day)	FCR (g/g)
Vitamin C	Zn
0	0	66.72 ± 7.10 ^b	48.93 ± 5.21 ^b	2.47 ± 0.28 ^a
240	0	60.34 ± 7.97 ^b	45.30 ± 4.37 ^b	2.66 ± 0.34 ^a
0	40	67.27 ± 9.83 ^b	49.33 ± 7.20 ^b	2.47 ± 0.33 ^a
240	40	78.41 ± 4.28 ^a	57.50 ± 3.14 ^a	2.09 ± 0.11 ^b

Means (±SD) within columns with different lower case letters differ significantly (P ≤ 0.05).

SEM standard error of the mean for main effects.

Table 5. The effect of diet supplementation by vitamin C and Zn on body weight (BW) and egg production (EP) of the laying hens.

	BW (kg/hen)		EP%
Groups	Initial	Final	Mon1	Mon2	Mon3	Total
Vitamin C (mg/kg)
0	1.495 ± 0.14	1.592 ± 0.11	74.60 ± 8.86	74.40 ± 9.73	76.56 ± 10.18	75.19 ± 9.27
240	1.560 ± 0.09	1.638 ± 0.20	69.75 ± 9.85	67.421 ± 3.52	73.40 ± 7.75	70.19 ± 10.03
Zn (mg/kg)
0	1.529 ± 0.09	1.632 ± 0.23	71.07 ± 9.95	68.311 ± 2.22	73.03 ± 9.63	70.80 ± 10.12
40	1.525 ± 0.15	1.598 ± 0.05	73.29 ± 9.31	73.511 ± 1.83	76.93 ± 8.25	74.58 ± 9.49
SEM	0.036	0.051	2.81	3.41	2.63	2.86
P value
Vitamin C	0.22	0.52	0.23	0.16	0.40	0.23
Zn	0.94	0.64	0.58	0.29	0.30	0.36
Vitamin C × Zn	0.68	0.85	0.87	0.44	0.44	0.90

Means ( ± SD) within columns with different lower case letters differ significantly (P ≤ 0.05).

SEM standard error of the mean for main effects.

Table 6. The effect of diet supplementation by vitamin C and Zn on egg quality traits of the laying hens.

Groups	Egg index (percent)	Yolk index (percent)	Shell weight (g)	Yolk colour	White weight (g)	Yolk weight (g)	Specific gravity
Vitamin C (mg/kg)
0	71.95 ± 2.21	47.27 ± 3.23	5.78 ± 0.42	7.13 ± 0.16	36.62 ± 2.13	19.02 ± 0.93	1.08 ± 0.008
240	72.44 ± 1.55	47.8 ± 12.29	5.91 ± 0.39	7.16 ± 0.22	37.39 ± 2.89	18.65 ± 0.48	1.09 ± 0.007
Zn (mg/kg)
0	72.62 ± 2.14	47.31 ± 3.49	5.87 ± 0.38	7.22 ± 0.21	35.62 ± 1.77^b	18.96 ± 0.70	1.09 ± 0.007
40	71.77 ± 1.57	47.77 ± 1.90	5.82 ± 0.44	7.08 ± 0.14	38.39 ± 2.44^a	18.72 ± 0.81	1.08 ± 0.008
SEM	0.545	0.845	0.123	0.056	0.633	0.222	0.002
P value
Vitamin C	0.53	0.65	0.45	0.72	0.39	0.25	0.14
Zn	0.28	0.70	0.76	0.09	0.005	0.45	0.32
Vitamin C × Zn	0.26	0.80	0.73	0.73	0.78	0.79	0.32

Means ( ± SD) within columns with different lower case letters differ significantly (P ≤ 0.05).

SEM standard error of the mean for main effects.

Table 7. The effect of diet supplementation by vitamin C and Zn on egg quality traits of the laying hens.

Groups		Haugh unit	Shell thickness (mm)
Vitamin C	Zn
0	0	76.52 ± 2.25 ^b	39.72 ± 2.02 ^b
240	0	82.10 ± 5.29 ^a	42.88 ± 0.98 ^a
0	40	78.06 ± 2.32 ^ab	42.00 ± 2.14 ^ab
240	40	76.54 ± 3.99 ^b	41.49 ± 1.84 ^ab
Vitamin C (mg/kg)
0		77.29 ± 2.32	40.86 ± 2.32
240		79.32 ± 5.32	42.19 ± 1.58
Zn (mg/kg)
0		79.31 ± 4.85	41.30 ± 2.24
40		77.30 ± 3.21	41.74 ± 1.92
SEM		1.065	0.522
P value
Vitamin C		0.19	0.08
Zn		0.19	0.55
Vitamin C × Zn		0.02	0.02

Means (± SD) within columns with different lower case letters differ significantly (P ≤ 0.05).

SEM standard error of the mean for main effects.

Table 8. The effect of diet supplementation by vitamin C and Zn on blood biochemical parameters of the laying hens.

Groups		Glucose (mg/dl)	Cholesterol (mg/dl)	Albumin (g/dl)	Total protein (g/dl)	Triglycerides (mg/dl)
Vitamin C	Zn
0	0	19.57  ±  245.50	37.34  ±  176.50	0.99  ±  3.02	0.46  ±  5.25	95.93  ±  1885.25
240	0	13.20  ±  232.33	50.04  ±  167.25	1.57  ±  3.52	0.49  ±  5.17	237.66  ±  1621.25
0	240	13.09  ±  221.75	29.39  ±  150.33	0.45  ±  3.70	0.40  ±  5.43	123.57  ±  1456.00
240	40	11.84  ±  227.40	44.57  ±  176.20	1.29  ±  3.88	0.27  ±  5.34	254.38  ±  1634.60
Vitamin C (mg/kg)
0		233.62 ± 19.97	163.41 ± 34.36	3.36 ± 0.83	5.34 ± 0.41	1670.62 ± 249.67
240		229.86 ± 11.68	171.72 ± 44.21	3.70 ± 1.33	5.25 ± 0.37	1627.92 ± 168.84
Zn (mg/kg)
0		239.91 ± 17.29	171.87 ± 41.17	3.27 ± 1.24	5.21 ± 0.44	1753.25 ± 219.23
40		224.57 ± 11.97	163.26 ± 39.51	3.79 ± 1.01	5.38 ± 0.30	1545.30 ± 223.34
SEM		5.262	15.135	0.433	0.147	72.209
P value
Vitamin C		0.62	0.70	0.69	0.58	0.68
Zn		0.07	0.69	0.41	0.41	0.06
Vitamin C × Zn		0.23	0.42	0.96	0.79	0.05

Means (±SD) within columns with different lower case letters differ significantly (P ≤ 0.05).

SEM standard error of the mean for main effects.

Table 9. The effect of diet supplementation by vitamin C and Zn on blood biochemical and SEM.

Groups	T3 (ng/ml)	T4 (μgeq/ml)	Zn concentration (μg/dL)	Heterophile to lymphocyte ratio
Vitamin C (mg/kg)
0	2.78 ± 0.19	3.35 ± 1.33	12.57 ± 3.96	0.32 ± 0.19
240	2.47 ± 0.21	3.20 ± 0.73	12.71 ± 2.01	0.33 ± 0.18
Zn (mg/kg)
0	2.66 ± 0.63	3.33 ± 0.88	12.62 ± 2.78	0.23 ± 0.08 ^b
40	2.60 ± 0.31	3.21 ± 1.19	12.66 ± 3.47	0.43 ± 0.20 ^a
SEM	0.206	0.377	1.190	0.046
P value
Vitamin C	0.31	0.78	0.93	0.87
Zn	0.83	0.82	0.98	0.005
Vitamin C × Zn	0.70	0.34	0.67	0.83

Means (±SD) within columns with different lower case letters differ significantly (P ≤ 0.05).

SEM standard error of the mean for main effects haematological parameters of the laying hens.