Table 7. Effect of Na on total tract retention of nitrogen (N) and minerals of 24-d old broilers fed diet with or without phytase

Na level1) Phytase2) N Ca P Mg Na K
Low None 0.65ab 0.60a 0.56b 0.25a 0.64b 0.35b
Plus 0.67a 0.58a 0.62a 0.29a 0.73a 0.42a
Mid None 0.61b 0.50b 0.49c 0.18a 0.41d 0.28c
Plus 0.65ab 0.56a 0.55b 0.21a 0.47c 0.29bc
High None 0.50c 0.27c 0.28d –0.13b 0.09f 0.09d
Plus 0.67a 0.60a 0.63a 0.26a 0.35e 0.35b
SEM 0.05 0.03 0.02 0.06 0.02 0.03
Main effects
Na level 0.65a 0.59a 0.59a 0.27a 0.68a 0.39a
Low 0.63a 0.53b 0.52b 0.20a 0.44b 0.25b
Mid 0.59b 0.44c 0.46c 0.08b 0.22c 0.22c
High
Phytase
None 0.58b 0.46b 0.44b 0.10b 0.38b 0.24b
Plus 0.66a 0.58a 0.60a 0.26a 0.52a 0.35a
Source of variation
Na *** *** *** *** *** ***
Phytase *** *** *** *** *** ***
Na × phytase *** *** *** *** *** ***
Means were obtained from 6 replicates (7 birds per cage).
Means within a column without common superscript are statistically different (p < 0.05).
Low, 1.5 g Na/kg; Mid, 2.5 Na/kg; High, 3.5 g Na/kg.
None, without phytase; plus, with (500 U/kg) phytase.
p < 0.001.