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Table 5 Multivariable linear mixed models related to performance and health parameters in 2309 flocks from 358 broiler farms in 7 EU member states

From: Risk factors for poor health and performance in European broiler production systems

Model Dependent variable Independent variablea p-value B-value
1 Overall mortality rate Mortality rate after 7 days < 0.001 1.03
Floor qualityb < 0.001 - 0.72
Neonatal septicemia < 0.001 0.22
2 First week mortality rate Floor quality 0.004 - 0.67
Ventilation typec < 0.001 0.72
No other professional activities by farmer < 0.001 0.24
Neonatal septicemiad 0.014 - 0.12
3 Mortality rate after seven days Floor quality 0.046 - 0.35
4 Dead on arrival Light management during catchinge 0.003 0.09
Type of drinking system < 0.001 - 0.41
Daily growth (g/d) < 0.001 0.01
5 Condemnation rate Type of drinking system 0.001 - 1.40
Daily growth (g/d) < 0.001 0.05
Feed withdrawal time < 0.001 - 0.12
Number of birds in the broilerhouse 0.002 0.02
Presence of recirculation vents 0.039 0.25
Septicemia after seven days 0.012 0.23
Type of feed < 0.001 0.75
Ventilation typec,f 0.057 - 0.31
6 Feed conversion rate Daily growth (g/d) < 0.001 - 0.01
Light intensity adaptations 0.013 0.02
Ventilation typec 0.001 - 0.03
Necrotic enteritis problems 0.014 - 0.02
Daily check of drink water flow 0.002 - 0.03
7 Daily growth Feed conversion rate < 0.001 - 29.35
Coccidiosis problems 0.004 1.33
8 European production index Sex of day old chicksg <  0.001 34.54
Dysbacteriosis problems 0.002 14.97
Evaluation of daily registered results < 0.001 - 33.94
Daily inspection of feed and water system 0.029 - 12.80
Type of drinking systemh 0.006 54.37
Type of feedi 0.024 - 13.01
  1. aOnly the statistically significant risk factors in the final models are presented; bThe reference used for floor quality was a floor in perfect conditions without cracks; cThe reference used for type of ventilation was roof ventilation; dThis was only the case in tunnel-ventilated broiler houses; eThe reference for light adaptation was dimming the light intensity; fInterpreted as a trend, as it was not significant (p > 0.05); gIf only male chicks were housed, a higher EPI was present; hThe reference used for drinking system was the nipple drinking system; iOnly the case when dysbacteriosis was absent in the flock