Table 3.

Effects of light intensity and flooring type on heterophil-to-lymphocyte (H:L) ratios, serum corticosterone (CORT) concentrations (ng/mL), IRT eye and beak surface temperatures (°C), core body temperatures (°C), and the latency-to-lie (LTL) time (s) when tested individually (LTLI) and in groups of 5 pen mates (LTLG) of broilers in pens with 2, 5, or 10 lx light intensity (L) on litter or wire flooring (F) on day 56 to 58 in study 1 and day 55 to 57 in study 2.

Flooring (F)	Litter			Wire			P-value2
Light lx (L)	2	5	10	2	5	10	SEM	L	F	L∗F
Study 1
H:L	0.32b	0.30b	0.36b	0.59a	0.78a	0.60a	0.26	NS	0.002	NS
CORT	5.91b	5.57b	5.63b	6.89a	7.19a	6.56a	1.16	NS	0.0004	NS
Eye temp	33.03a	33.28a	33.73a	31.70c	32.21b,c	32.50b,c	0.26	0.02	0.0001	NS
Beak temp	35.23a	35.00a	35.35a	32.69b	30.05c	33.29a,b	0.54	0.002	0.0001	0.03
LTL1
LTLG	157.0	94.7	47.1	60.1	169.2	59.2	58.72	NS	NS	NS
LTLI	129.8	53.6	82.8	101.0	231.8	134.7	53.94	NS	NS	NS
Study 2
H:L	0.24b	0.32b	0.40b	0.48a	0.45a	0.40a	0.20	NS	0.04	NS
CORT	7.17a	7.23a	6.41b	7.64a	7.57a	7.11b	1.09	0.02	0.02	NS
Eye temp	35.31	35.63	35.81	35.62	35.44	35.62	0.20	NS	NS	NS
Beak temp	36.29	37.18	36.96	36.96	36.27	36.95	0.33	NS	NS	NS
Core temp	41.83a,b	41.96a,b	42.03a,b	41.58b	41.83a,b	42.07a	0.12	0.03	NS	NS
LTL
LTLG	71.2	44.1	99.5	148.7	44.8	87.6	44.8	NS	NS	NS
LTLI	133.1	116.5	126.9	192.0	96.4	85.9	44.1	NS	NS	NS

^a,bMeans not sharing the same superscript letter across each row differ at P ≤ 0.05.

Abbreviation: lx, lux.

¹The LTL test was conducted in the hallway of the facility on day 57 and 58 in study 1 and day 56 and 57 in study 2. Five birds were subjected to the LTL test individually (LTLI) and in groups of 5 (LTLG), and data are reported as means for the pen of birds.

²ANOVA P-values represent the overall effects, the main effects of light intensity (L) and flooring type (F) and the interaction of light intensity and flooring type (L∗F).