Table 4.

Reproductive hormones in plasma of Chinese Yellow broiler breeders fed diets with different iron contents.

	Dietary Fe content, mg/kg						P-value1
Hormone2	44	58	72	86	100	SEM1	Fe level	Linear	Quadratic
LH, mIU/mL	4.82	4.53	4.63	4.71	5.23	0.148	0.041	0.104	0.007
FSH, mIU/mL	2.02	1.98	1.98	2.25	1.65	0.179	0.241
Progesterone, ng/mL	0.140	0.224	0.167	0.145	0.148	0.025	0.605
Estradiol, pg/mL	626	799	899	882	722	102	0.328

¹Standard error of the mean from ANOVA (n = 6), linear and quadratic contrasts examined only when Fe level was significant.

²LH: luteinizing hormone; FSH: follicle-stimulating hormone.