Effects of different levels of cottonseed meal on laying performance, egg quality, intestinal immunity and hepatic histopathology in laying hens

Figures & data

Figure 1. Hepatic histology in laying hens fed a control diet supplemented with 0 (A), 20 (B),70 (C), 120 (D) and 170 mg/kg FG(E) (haematoxylin-eosin staining, original magnification×40). Hepatic histology shows acidophil body (arrows) in mild hepatitis in FG 70 (C), FG 120 (D) and FG 170 (E) groups.

Table 1. Composition and nutrient levels of experimental diets (as-feed basis) (%).

Items	Content
	Control group	FG20	FG70	FG120	FG170
Ingredients
Corn	60.93	61.05	60.84	60.65	60.44
Soybean oil	1.75	1.85	2.35	2.85	3.38
Cottonseed meal	0.00	1.95	6.75	11.55	16.35
Soybean meal	25.76	23.58	18.34	13.10	7.90
Limestone	9.00	9.00	9.00	9.00	9.05
CaHPO4	1.90	1.90	1.90	1.90	1.80
NaCl	0.15	0.15	0.15	0.15	0.15
Vitamin premix^a	0.02	0.02	0.02	0.02	0.02
Minerals premix^b	0.20	0.20	0.20	0.20	0.20
Choline chloride (50%)	0.20	0.20	0.20	0.20	0.20
Methionine	0.09	0.10	0.10	0.10	0.11
Lysine	0.00	0.00	0.15	0.28	0.40
Total	100.00	100.00	100.00	100.00	100.00
Calculated chemical composition (%)
ME (MJ/kg)	11.62	11.61	11.61	11.61	11.63
Crude protein	16.72	16.72	16.71	16.71	16.73
Calcium	3.83	3.83	3.83	3.82	3.81
Total phosphorus	0.64	0.65	0.67	0.68	0.68
Methionine	0.36	0.36	0.36	0.36	0.36
Lysine	0.99	0.94	0.95	0.95	0.94
Free gossypol (mg/kg) (Calculated)	0.00	20.08	69.53	118.97	168.41
Free gossypol (mg/kg) (Measured)	0.00	21.01	70.63	121.72	172.48

Notes: ^avitamin premix provided the following per kilogram of diet:vitamin A,12,500 IU; vitamin D3,2,500 IU; vitamin E,15 IU; vitamin K3,2.65 mg; vitamin B1,2 mg; vitamin B2,6 mg; vitamin B12,0.025 mg; nicotinic acid,50 mg; calcium pantothenate, 12 mg; biotin, 0.0325 mg;folic acid, 1.25 mg.

^bThe mineral premix provided the following per kg of diet: iron, 80 mg;copper,8 mg;manganese, 100 mg;zinc,75 mg;iodine, 0.35 mg;selenium, 0.15 mg.

Table 2. Effects of different levels of free gossypol on laying performance in laying hens¹.

Items	Treatments^2					SEM	P-value
	0	20	70	120	170		ANOVA	Linear	Quadratic
ADFI (g/d)	146.69	136.81	152.10	145.06	149.97	3.3084	0.643	0.471	0.912
Egg production (%)	74.52	74.44	83.57	74.98	79.53	1.1578	0.068	0.234	0.284
Average egg weight (g)	62.47	63.34	64.72	63.38	63.36	0.3776	0.473	0.607	0.163
FCR (g/g)	2.00	1.85	1.83	1.97	1.88	0.5616	0.835	0.877	0.720

Notes: ¹Values are means, n=7.

²Control group, without FG; FG20, contain 20 mg/kg FG; FG70, contain 70 mg/kg FG; FG120, contain 120 mg/kg FG; FG170, contain 170 mg/kg FG.

Table 3. Effects of different levels of free gossypol on egg quality¹.

Items	Treatments^2					SEM	P-value
	0	20	70	120	170		ANOVA	Linear	Quadratic
Yolk colour	7.01	7.00	6.27	6.90	6.77	0.1004	0.143	0.479	0.127
Eggshell thickness(mm)	0.37	0.43	0.38	0.39	0.38	0.0106	0.363	0.657	0.773
Eggshell strength (N/m^2)	34.14	36.41	35.44	36.89	32.83	0.5953	0.209	0.467	0.064
Haugh unit	79.10	77.44	79.57	81.43	79.79	1.1139	0.855	0.468	0.726
Egg shape index	1.33	1.33	1.31	1.31	1.32	0.0046	0.410	0.179	0.188

Notes: ¹Values are means, n=7.

²Control group, without FG; FG20, contain 20 mg/kg FG; FG70, contain 70 mg/kg FG; FG120, contain 120 mg/kg FG; FG170, contain 170 mg/kg FG.

Table 4. Effects of different levels of free gossypol on organ index¹.

Items	Treatments ^2					SEM	P-value
	0	20	70	120	170		ANOVA	Linear	Quadratic
Liver index (g/kg)	2.54	2.74	2.49	2.24	2.32	0.0611	0.116	0.441	0.278
Lungs index (g/kg)	0.43	0.46	0.45	0.38	0.41	0.0097	0.131	0.272	0.149
Kidney index (g/kg)	0.75	0.754	0.73	0.77	0.76	0.0243	0.990	0.972	0.900
Heart index (g/kg)	0.51	0.41	0.43	0.42	0.41	0.0118	0.043	0.079	0.060
Spleen index (g/kg)	0.08	0.08	0.09	0.09	0.08	0.0023	0.917	0.827	0.997

Notes: ¹Values are means, n=7.

²Control group, without FG; FG20, contain 20 mg/kg FG; FG70, contain 70 mg/kg FG; FG120, contain 120 mg/kg FG; FG170, contain 170 mg/kg FG.

Table 5. Effects of different levels of free gossypol on intestinal immunity¹.

Items		Treatments ^2					SEM	P-value
		0	20	70	120	170		ANOVA	Linear	Quadratic
Jejunum	sIgA^3	0.92^a	0.91^a	0.80^ab	0.75^b	0.78^ab	0.0186	0.019	0.431	0.342
	IL-2^3	308.56	285.96	295.76	281.20	253.70	6.2915	0.105	0.015	0.521
	IL-6^3	224.31	231.06	218.11	229.34	240.13	5.1316	0.730	0.416	0.458
	TNF-α^3	187.74	197.476	212.572	220.20	204.467	4.6330	0.229	0.097	0.142
Ileum	sIgA	1.12^ab	1.21^a	1.05^abc	0.85^c	0.96^bc	0.0263	0.002	0.001	0.995
	IL-2	386.91^a	365.16^ab	348.06^bc	278.33^d	316.29^c	4.0743	0.000	0.000	0.059
	IL-6	189.83	202.69	203.80	213.31	201.24	3.7708	0.430	0.219	0.199
	TNF-α	247.73^b	272.63^ab	287.50^ab	313.91^a	299.26^ab	6.0713	0.018	0.002	0.193

Notes: ¹Values are means, n=7. means in a row with superscripts without a common letter differ, P＜0.05.

²Control group, without FG; FG20, contain 20 mg/kg FG; FG70, contain 70 mg/kg FG; FG120, contain 120 mg/kg FG; FG170, contain 170 mg/kg FG.

³sIgA, Secretory immunoglobulin A; IL-2, interleukin 2; IL-6, interleukin 6; TNF-α, tumour necrosis-α.