Table 3

Intraclass correlations for body weight, plasma creatine kinase activity, pH, tenderness, breast and thigh muscle colour at 8 weeks of age for 34 genetic lines of chickens calculated over all genetic lines (tw) and within category (twb)
Trait
 Intraclass correlation1
 Category average
 SED2

tw
 twb
 Broiler
 Layer
 Traditional
Weight and CK
Live weight, kg
 0.96§
 0.68§
 3.67
 1.01
 1.06
 0.168***
ln CK (iu/mL)
 0.89§
 0.62§
 6.73 (835)
 5.20 (181)
 5.35 (211)
 0.161***
Breast muscle pH and toughness
pHi
 0.34‡
 0.35
 6.09
 6.16
 6.16
 0.017***
pHu
 0.68§
 0.51‡
 5.69
 5.87
 5.81
 0.034***
ΔpH
 0.69‡
 0.33‡
 0.40
 0.29
 0.35
 0.036**
Force N
 0.58‡
 0.40†
 31.1
 36.1
 35.5
 1.04***
Breast muscle colour
Lightness (L*)
 0.52§
 0.50‡
 55.0
 53.6
 53.5
 0.83
Redness (a*)
 0.49‡
 0.14
 2.95
 5.74
 5.21
 0.372***
Yellowness (b*)
 0.72§
 0.35‡
 2.14
 5.41
 3.77
 0.364***
Thigh muscle colour
Lightness (L*)
 0.44‡
 0.45‡
 51.3
 51.9
 52.1
 1.03
Redness (a*)
 0.20†
 0.20
 6.55
 6.24
 7.03
 0.541
Yellowness (b*)
 0.62§
 0.32‡
 -1.34
 1.45
 0.92
 0.411***

The means for broiler, layer and traditional lines of chickens are also presented

1Significance of between line (breed) variance component (t-test): † p < 0.05; ‡ p < 0.01; § p < 0.001

2Standard error of a difference between two category means: ** p < 0.05; *** p < 0.001

Sandercock et al. Genetics Selection Evolution 2009 41:8   doi:10.1186/1297-9686-41-8