Table 6.

Factor associated with the percentage of bruising of 13,581 truckloads of broilers by one of Thailand's largest broiler producers raised without an antibiotic program and slaughtered in 2021.

Variable	Estimates1	SE	Statistic	P value	95% confidence interval
Season
Winter	−0.067	0.010	−6.546	<0.001	−0.0871	−0.0470
Summer	−0.055	0.011	−5.202	<0.001	−0.0754	−0.0341
Rainy	Ref
Time of transport2
Night	−0.031	0.007	−4.498	<0.001	−0.0449	−0.0176
Morning	−0.032	0.013	−2.429	0.015	−0.0572	−0.0061
Day	Ref
Sex
Male	−0.043	0.011	−3.811	<0.001	−0.0643	−0.0206
Female	−0.026	0.011	−2.399	0.016	−0.0480	−0.0048
Mixed sex	Ref
Age
40–43 d	−0.070	0.018	−3.832	<0.001	−0.1060	−0.0342
44–47 d	−0.074	0.017	−4.278	<0.001	−0.1080	−0.0402
48–51 d	−0.027	0.031	−0.865	0.387	−0.0882	0.0342
52–55 d	−0.019	0.058	−0.321	0.748	−0.1320	0.0948
56–71 d	Ref
Mean body weight (g)	0.0002	0.0000	7.964	<0.001	0.0001	0.0002
Mortality and culling (%)	−0.0053	0.0018	−2.956	0.003	−0.0088	−0.0017
Weight per crate (kg)	−0.0194	0.0025	−7.919	<0.001	−0.0242	−0.0146
Transport duration (min)	0.0003	0.0001	3.024	0.002	0.00009	0.00042
Lairage time (min)	0.0002	0.0001	3.665	<0.001	0.0001	0.0003

Intraclass correlation coefficient (ICC) = 0.03.

¹Estimates (β) indicate how likely an outcome is to occur in one context relative to another or one unit increase or decrease in the predictor to a β value increase or decrease in the outcome.

²Time of transport (night = 18:00–04:00, morning = 04:00–08:00, day = 8:00–8:00).