Table 1.

Effect of enrichment materials on total plumage scores during the rearing period.

Age of chicks/pullets (weeks)	Strain	Total plumage scores (grouped medians)		P
		CON	EXP
2	LB/LSL	0.15	0.09	0.006
	LB	0.07	0.06	0.687
	LSL	0.23	0.12	<0.001
4	LB/LSL	0.29	0.14	0.001
	LB	0.13	0.10	0.596
	LSL	0.49	0.18	<0.001
6	LB/LSL	0.17	0.13	0.247
	LB	0.09	0.10	0.947
	LSL	0.26	0.16	0.124
10	LB/LSL	0.37	0.27	0.063
	LB	0.64	0.43	0.026
	LSL	0.15	0.13	0.317
14	LB/LSL	0.50	0.36	0.028
	LB	1.34	0.80	0.001
	LSL	0.03	0.04	0.473
18	LB/LSL	0.29	0.26	0.565
	LB	0.61	0.50	0.437
	LSL	0.08	0.08	1.000

Bold values indicate significant differences between study groups.

Abbreviations: CON, control group (without additional enrichment materials); EXP, enrichment group (supply of additional enrichment materials); LB, Lohmann Brown classic; LSL, Lohmann Selected Leghorn classic.