Effect of dietary nonphytate phosphorus on laying performance and small intestinal epithelial phosphate transporter expression in Dwarf pink-shell laying hens

Table 6 Effects of different dietary phosphorus levels on gene expression of duodenal NaP-IIb, calbindin, vitamin D receptor, and protein abundance of calbindin and vitamin D receptor of laying hens at 41 wk of age

Nonphytate phosphorus, %	Duodenal NaP-IIb mRNA¹	Duodenal calbindin mRNA¹	Duodenal vitamin D receptor mRNA¹	Duodenal calbindin protein²	Duodenal vitamin D receptor protein²
0.20	1.16^a	0.96^c	1.37^b	0.21^b	0.17^d
0.25	0.76^b	26.23^a	3.17^a	0.29^b	0.27^c
0.30	0.64^b	16.30^a	1.43^b	0.72^a	0.62^a
0.35	0.65^b	17.40^a	0.94^b	0.49^a	0.49^b
0.40	0.26^c	2.49^b	1.27^b	0.21^b	0.19^d
SEM	0.054	2.29	0.160	0.05	0.04
P-value	0.000	0.000	0.000	0.000	0.000
Linear	0.000	0.684	0.000	0.036	0.002
Quadratic	0.678	0.000	0.000	0.000	0.000

^a–dWithin comparisons, means in a column with no common superscript differ significantly (P < 0.05) (n = 5).
¹mRNA relative expression is normalized to β-actin, results are expressed as 2-△△Ct.
²Relative optical densityof protein to β-actin.

ISSN: 2049-1891