Effects of different levels of zinc-glycine and zinc hydroxide on the performance, carcass quality, immunity and duodenum morphometric of the broiler chickens

Figures & data

Table 1. Ingredients and chemical composition of the basal rations.

Ingredients, %	Starter period (1–10 days)	Grower period (11–24 days)	Finisher period (25–42 days)
Corn	580.770	590.950	650.330
Soybean meal	360.620	330.620	280.310
Soybean oil	10.440	20.960	20.810
Di calcium-phosphate	10.740	10.500	10.560
CaCO3	10.340	10.110	10.150
NaCl	0.20	0.200	0.200
Vitamin premix^a	0.250	0.250	0.250
Mineral premix^b	0.250	0.250	0.250
L-lysine	0.150	–	0.200
DL-methionine	0.240	0.160	0.140
Calculated analysis
Energy (ME), kcal/kg	3000	3100	3200
Protein, %	210.120	20.160	180.280
Calcium, %	10.008	0.860	0.870
Available phosphorus, %	0.480	0.430	0.430
Lysine, %	10.210	10.060	0.930
Methionine, %	0.560	0.470	0.420
Methionine + cysteine	0.900	0.800	0.730
Threonine	0.780	0.750	0.670

^aEach kilogram contains: 3,500,000 IU vit0.A,1,000,000 IU vit0.D3, 9000 IU vit0.E,1000 mg vit0.k3,900 mg vit B1,5000 mg vit B3,1500 mg vit B5,150 mg vitB6, 500 mg vit B9,7.5 mg vit B12,250000 mg choline and 500 mg Biotin0.

^bEach kilogram contains:120 mg Mn, 20 mg Fe, 16 mg Cu, 1.25 mg I, 0.3 mg Se, 0 mg Zn.

ME: Metabolizable Energy.

Table 2. Comparison of mean performance traits in chicks fed with different levels of glycine-zinc and zinc-hydroxide.

Treatment	Weight gain, g	Feed intake, g	Feed conversion ratio	European production index
	Total period	Total period	Total period	Total period
Zn-H, mg/kg diet
0	2863.1600^c	4714.1600^b	1.6400^b	231.9100^b
50	2879.4100^b	4547.8300^c	1.6400^b	240.9300^a
100	2891.5000^a	4837.3300^a	1.6700^a	236.5700^b
p-value	p < .0010	p < .0010	p < .0010	p < .0010
SEM	5.7220	24.0360	0.0065	1.1840
Zn-Gly, mg/kg diet
0	2877.9100	4755.5000^b	1.6500^b	240.0200
50	2875.3300	4759.9100^b	1.6500^b	239.0600
100	2880.1300	4781.9100^a	1.6600^a	238.3300
p-value	.1950	.0100	.0100	.1890
SEM	3.0260	10.3020	0.0039	0.9250
Zn-H (0 mg/kg diet)- Zn-Gly (0 mg/kg diet)	2852.0000^e	4703.5000^c	1.6470^cd	238.6000^bc
Zn-H (50 mg/kg diet)- Zn-Gly (0 mg/kg diet)	2867.0000^d	4715.5000^c	1.6450^d	241.1000^ab
Zn-H (100 mg/kg diet)- Zn-Gly (0 mg/kg diet)	2870.0000^d	4723.0000^c	1.6470^cd	239.9000^ab
Zn-H (0 mg/kg diet)- Zn-Gly (50 mg/kg diet)	2882.0000^c	4726.5000^c	1.6400^d	242.8000^a
Zn-H (50 mg/kg diet)- Zn-Gly (50 mg/kg diet)	2873.0000^d	4727.5000^c	1.6470^cd	240.5000^ab
Zn-H (100 mg/kg diet)- Zn-Gly (50 mg/kg diet)	2883.0000^bc	4783.5000^b	1.6600^bc	239.9900^b
Zn-H (0 mg/kg diet)- Zn-Gly (100 mg/kg diet)	2899.5000^a	4836.5000^a	1.6700^ab	238.5700^bc
Zn-H (50 mg/kg diet)- Zn-Gly (100 mg/kg diet)	2885.5000^bc	4836.5000^a	1.6800^a	235.4000^d
Zn-H (100 mg/kg diet)- Zn-Gly (100 mg/kg diet)	2889.0000^b	4839.0000^a	1.6750^a	235.6000^cd
p-value	p < .0010	p < .0010	p < .0010	p < .0010
SEM	2.2900	9.7200	0.0030	0.4800

Means without superscript letters or with same superscript letters within the same column do not differ (p ≥ .05).

SEM: Standard error of means, Zn-H: Zinc hydroxide, Zn-Gly: Zinc-glycine.

Table 3. Comparison of mean relative weight of carcass parts in chicks fed with different levels of glycine-zinc and zinc-hydroxide.

Treatment	Thigh, %	Breast, %	Viscera*, %	Abdominal fat, %
Zn-H, mg/kg diet
0	21.9800	43.9900	9.1900^b	1.8500^c
50	24.2000	44.2300	9.2800^a	1.8600^b
100	24.2200	44.4300	9.2900^a	1.8700^a
p-value	.3000	.3700	p < .0010	p < .0010
SEM	0.9090	1.6680	0.3490	0.0703
Zn-Gly, mg/kg diet
0	23.4200	44.5600	9.3200	1.8600
50	24.1100	44.2400	9.2400	1.8600
100	22.0200	44.0300	9.2000	1.8600
p-value	.3900	.3800	.4900	.4800
SEM	0.4812	0.8822	0.1846	0.3723
Zn-H (0 mg/kg diet) – Zn-Gly (0 mg/kg diet)	22.9000	44.2600	9.2500	1.8700
Zn-H (50 mg/kg diet) – Zn-Gly (0 mg/kg diet)	24.1000	44.3800	9.2800	1.8700
Zn-H (100 mg/kg diet) – Zn-Gly (0 mg/kg diet)	24.2000	44.3600	9.2700	1.8700
Zn-H (0 mg/kg diet) – Zn-Gly (50 mg/kg diet)	23.4000	44.2900	9.2600	1.8600
Zn-H (50 mg/kg diet) – Zn-Gly (50 mg/kg diet)	24.1000	44.3300	9.2700	1.8600
Zn-H (100 mg/kg diet) – Zn-Gly (50 mg/kg diet)	24.2000	44.2500	9.2500	1.8600
Zn-H (0 mg/kg diet) – Zn-Gly (100 mg/kg diet)	24.1000	44.1200	9.2200	1.8600
Zn-H (50 mg/kg diet) – Zn-Gly (100 mg/kg diet)	24.0000	44.2300	9.2500	1.8600
Zn-H (100 mg/kg diet) – Zn-Gly (100 mg/kg diet)	24.1000	44.2000	9.2400	1.8600
p-value	0.1290	.4500	.5100	.3300
SEM	24.1000	212.6500	0.2000	0.0400

*Viscera include oesophagus, crop, gizzard, pancreas, liver, gall bladder, small and large intestine.

Means without superscript letters or without superscript letters within the same column do not differ (p ≥ .05).

SEM: Standard error of means, Zn-H: Zinc hydroxide, Zn-Gly: Zinc-glycine.

Table 4. Comparison of mean relative weight of immunity organs in chicks fed with different levels of glycine-zinc and zinc-hydroxide.

Treatment	Bursa of fabricus, %	Spleen, %	Thymus, %
Zn-H, mg/kg diet
0	0.14000^a	0.17000^c	0.35000^a
50	0.13000^b	0.18000^b	0.34000^a
100	0.12000^c	0.19000^a	0.31000^b
p-value	p < .00100	p < .00100	p < .00100
SEM	0.00086	0.00750	0.00750
Zn-Gly, mg/kg diet
0	0.13000	0.18000	0.34000^a
50	0.13000	0.18000	0.34000^a
100	0.13000	0.18000	0.31000^b
p-value	.23000	.60000	.01000
SEM	0.00045	0.00390	0.00390
Zn-H (0 mg/kg diet)- Zn-Gly (0 mg/kg diet)	0.17000^a	0.15000^c	0.35000^b
Zn-H (50 mg/kg diet)- Zn-Gly (0 mg/kg diet)	0.16000^a	0.16000^bc	0.35000^b
Zn-H (100 mg/kg diet)- Zn-Gly (0 mg/kg diet)	0.16000^a	0.17000^b	0.36000^ab
Zn-H (0 mg/kg diet)- Zn-Gly (50 mg/kg diet)	0.12000^c	0.17000^b	0.34000^b
Zn-H (50 mg/kg diet)- Zn-Gly (50 mg/kg diet)	0.13000^bc	0.17000^b	0.37000^a
Zn-H (100 mg/kg diet)- Zn-Gly (50 mg/kg diet)	0.14000^b	0.17000^b	0.31000^bc
Zn-H (0 mg/kg diet)- Zn-Gly (100 mg/kg diet)	0.09000^e	0.19000^a	0.31000^bc
Zn-H (50 mg/kg diet)- Zn-Gly (100 mg/kg diet)	0.12000^c	0.18000^ab	0.33000^ab^c
Zn-H (100 mg/kg diet)- Zn-Gly (100 mg/kg diet)	0.10000^de	0.18000^ab	0.30000^c
p-value	p < .00100	p < .00100	.02000
SEM	0.01000	0.00000	0.03000

Means without superscript letters or without superscript letters within the same column do not differ (p ≥ .05).

SEM: Standard error of means, Zn-H: Zinc hydroxide, Zn-Gly: Zinc-glycine.

Table 5. Comparison of mean small intestine morphometry in chicks fed with different levels of glycine-zinc and zinc-hydroxide.

Treatment	Villus height, μm	Villus width, μm	Crypt depth, μm	Villus height: crypt depth
Zn-H, mg/kg diet
0	1282.1000^c	135.9800	307.4500^b	4.2600^b
50	1882.2200^b	134.0300	351.6500^ab	5.4900^a
100	2011.9800^a	148.2500	373.6800^a	5.6500^a
p-value	p < .0010	.5900	.0400	p < .0010
SEM	143.7150	14.7520	28.3750	0.5040
Zn-Gly, mg/kg diet
0	1698.2900	137.3200	360.1400	4.7500
50	1712.6400	136.4300	328.9900	5.4200
100	1756.2700	144.5100	343.6500	5.2300
p-value	.3700	.8400	.5100	.3000
SEM	49.2120	14.5882	26.3950	0.4464
Zn-H (0 mg/kg diet)- Zn-Gly (0 mg/kg diet)	1063.5000^f	132.1000	314.2000^bc	3.4000^c
Zn-H (50 mg/kg diet)- Zn-Gly (0 mg/kg diet)	1326.6000^e	153.2000	312.1000^bc	4.3000^bc
Zn-H (100 mg/kg diet)- Zn-Gly (0 mg/kg diet)	1455.8000^d	122.5000	295.9000^c	5.0000^b
Zn-H (0 mg/kg diet)- Zn-Gly (50 mg/kg diet)	1932.4000^bc	136.8000	339.1000^ab^c	5.8000^ab
Zn-H (50 mg/kg diet)- Zn-Gly (50 mg/kg diet)	1841.4000^c	119.5000	337.1000^ab^c	5.0000^b
Zn-H (100 mg/kg diet)- Zn-Gly (50 mg/kg diet)	1872.6000^c	145.7000	336.6000^ab^c	5.6000^ab
Zn-H (0 mg/kg diet)- Zn-Gly (100 mg/kg diet)	2098.8000^a	142.9000	427.0000^a	5.0000^b
Zn-H (50 mg/kg diet)- Zn-Gly (100 mg/kg diet)	1969.8000^b	136.5000	295.6000^c	6.8000^a
Zn-H (100 mg/kg diet)- Zn-Gly (100 mg/kg diet)	1967.3000^b	165.2000	398.3000^ab	5.0000^b
p-value	p < .0010	.7600	.0300	p < .0010
SEM	57.1700	5.8800	11.4500	0.2000

Means without superscript letters or without superscript letters within the same column do not differ (p ≥ .05).

SEM: Standard error of means, Zn-H: Zinc hydroxide, Zn-Gly: Zinc-glycine.