Table 4. Effect of dietary palm kernel meal (PKM) and β-xylanase supplementation on egg quality of laying hens

Item Egg quality
Eggshell color1) Egg yolk color Haugh unit Eggshell strength (kg/cm2) Eggshell thickness (μm)
Color fan L* a* b*
Xylanase (%) PKM (%)
 0 0 12.7 54.4 19.8 30.4 8.4 91.4 4.4 407.0
10 12.8 53.6 20.7 30.3 8.7 91.9 4.5 410.1
 0.025 0 12.5 54.1 19.9 30.1 8.5 91.9 4.4 411.5
10 12.5 54.1 20.3 29.7 8.7 91.7 4.5 412.0
SEM 0.27 0.50 0.36 0.48 0.06 0.79 0.10 3.16
Main effect
 Xylanase (%)
  0 12.7 54.0 20.3 30.4 8.6 91.7 4.4 408.5
  0.025 12.5 54.1 20.1 29.9 8.6 91.8 4.5 411.7
  SEM 0.19 0.35 0.26 0.34 0.04 0.56 0.07 2.24
 PKM (%)
  0 12.6 54.2 19.8 30.2 8.4 91.6 4.4 409.2
  10 12.7 53.9 20.5 30.0 8.7 91.8 4.5 411.0
  SEM 0.19 0.35 0.26 0.34 0.04 0.56 0.07 2.24
Effect (p-value)
 Xylanase 0.419 0.865 0.599 0.355 0.675 0.888 0.790 0.322
 PKM 0.757 0.496 0.080 0.645 <0.001 0.854 0.313 0.567
 Xylanase × PKM 0.938 0.407 0.467 0.784 0.410 0.640 0.901 0.682
Eggshell color was measured by the color fan scale and CIE [11].