Table 3.

Main effects of treatment and trial and interaction effect on day 45 live body weight, stress, and welfare measures on broilers reared under an intermittent, short-dawn/dusk photoperiod (ISD) or an increasing, long-dawn/dusk photoperiod (ILD) day 0 to 45.

Measure	Day 45 body weight	Plasma CORT	H/L ratio	Hock burn	Foot pad dermatitis	Feather condition
Units	kg	pg/mL		04	0-4	0-3
ISD1	2.57	4,484.62	0.58	0.87	1.24	1.04
ILD1	2.67	3,312.46	0.39	0.58	1.27	1.01
ISD2	2.65	1,772.07	0.44	0.43	0.82	1.00
ILD2	2.77	1,202.34	0.28	0.73	1.48	1.03
ISD3	2.95	3,173.07	0.41	0.73	1.43	1.01
ILD3	2.97	1,483.71	0.28	1.06	1.79	1.00
ISD4	2.80	1,730.07	0.89	0.34	1.08	1.00
ILD4	2.90	904.72	1.12	0.27	0.90	1.00
Pooled SEM	0.01	140.80	0.02	0.02	0.03	0.00
Main effect treatment
ISD	2.82a	2,789.97a	0.54a	0.60b	1.14b	1.01
ILD	2.74b	1,725.81b	0.37b	0.67a	1.36a	1.01
P-value treatment	<0.001	<0.001	<0.001	0.044	<0.001	0.616
Main effect trial
1	2.62d	3,898.54a	0.49b	0.72	1.25	1.03
2	2.71c	1,487.20c	0.36c	0.59	1.15	1.01
3	2.96a	2,328.39b	0.35c	0.91	1.61	1.00
4	2.85b	1,317.41c	0.63a	0.30	0.99	1.00
P-value trial	<0.001	<0.001	<0.001	<0.001	<0.001	0.001
P-value treatment × trial	0.191	0.430	0.913

^a-cValues within a column with different superscripts differ (P < 0.05).

Abbreviations: CORT, corticosterone; H/L, heterophil/lymphocyte.