Table 8 Effects of dietary Fe on mRNA levels of tissue Fe-containing enzymes of broilers on d 21

Control¹

0

1.01

1.02

1.01

1.01

1.01*

1.03*

1.01

1.00

1.01

FeSO₄∙7H₂O¹

20

1.05

0.97

0.98

1.02

1.05

1.05

0.88

0.89

1.01

40

0.96

1.02

1.21

0.91

1.10

1.17

1.09

1.08

0.99

60

0.95

0.95

1.19

1.02

1.19

1.30

0.84

0.94

1.16

Fe-Prot ES¹

20

1.13

0.93

0.99

0.98

1.16

1.23

0.91

0.93

1.08

40

1.13

0.90

1.18

0.98

1.31

1.36

1.00

0.94

1.08

60

1.13

0.92

0.91

0.97

1.42

1.46

0.94

0.99

1.21

Feed grade NaFeEDTA¹

20

1.54

1.03

1.11

1.04

1.19

1.20

1.07

0.94

1.08

40

1.58

0.95

1.19

0.85

1.30

1.47

0.94

1.02

1.08

60

1.48

1.11

1.02

0.94

1.44

1.51

1.01

1.12

1.15

Food grade

NaFeEDTA¹

20

1.26

0.98

1.03

0.97

1.26

1.39

0.94

0.90

0.94

40

1.27

0.98

1.15

0.93

1.23

1.37

0.96

0.86

1.07

60

1.49

0.91

0.95

1.00

1.35

1.51

0.96

0.85

1.23

Pooled SE

0.13

0.07

0.11

0.07

0.08

0.09

0.1

0.07

0.09

Fe source²

FeSO₄∙7H₂O

0.99^C

0.98

1.13

0.98

1.11^B

1.17^B

0.94

0.97

1.05

Fe-Prot ES

1.13^BC

0.92

1.03

0.98

1.30^A

1.35^A

0.95

0.95

1.13

Feed grade NaFeEDTA

1.53^A

1.03

1.11

0.95

1.31^A

1.39^A

1.01

1.03

1.10

Food grade NaFeEDTA

1.34^AB

0.96

1.04

0.97

1.28^A

1.42^A

0.95

0.87

1.08

Pooled SE

0.08

0.04

0.07

0.04

0.06

0.05

0.05

0.04

0.06

Added Fe level³, mg/kg

20

1.25

0.98

1.03

1.00

1.16^b

1.22^b

0.95

0.91

1.03^b

40

1.24

0.96

1.18

0.92

1.24^ab

1.34^ab

1.00

0.97

1.06^ab

60

1.26

0.97

1.01

98

1.35 ^a

1.45^a

0.94

0.97

1.18^a

Pooled SE

0.07

0.03

0.06

0.04

0.04

0.05

0.05

0.04

0.05

P-value

Fe source

< 0.0001

0.2679

0.6672

0.9303

0.0143

0.0048

0.8188

0.0792

0.8131

Added Fe level

0.9562

0.9508

0.0954

0.2172

0.0091

0.0027

0.6265

0.4327

0.0423

Fe Source × added Fe level

0.8794

0.6658

0.8536

0.8476

0.9340

0.8465

0.6108

0.5054

0.9464

Linear effect⁴

–

–

–

–

0.0003

0.0001

–

–

0.0596