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. 2018 Jun 19;97(11):3767–3785. doi: 10.3382/ps/pey243

Table 3.

Parameter estimates and standard error for the models quantifying the effect of the different rearing system characteristics on the ADG, ADFI, and FCR of broiler chickens.

ADG ADFI FCR
Variable1 (g/d; n = 679) P-value (g/d; n = 664) P-value (g:g; n = 670) P-value
Intercept −25.70 13.03 0.0536 −109.14 33.75 0.0021 0.965 0.201 <0.0001
ED 1.02 0.355 0.0044 0.271 0.783 0.7294 0.002 0.006 0.6959
ED × ED 0.019 0.006 0.0020 0.094 0.013 <0.0001 0.0004 0.0001 <0.0001
IA 4.89 0.35 <0.0001 7.66 0.75 <0.0001 −0.012 0.005 0.4333
IA × IA −0.077 0.004 <0.0001 −0.064 0.008 <0.0001 0.00073 0.00007 <0.0001
Breed Aviagen −4.29 8.71 0.3454 3.40 23.45 0.7686 −0.0002 0.1261 0.6975
Aviagen × Cobb Vantress −63.26 25.36 −177.10 65.64 −0.560 0.331
Cobb Vantress −8.94 9.32 −5.46 24.83 −0.006 0.138
Group Grimaud 4.93 10.83 −4.28 28.15 −0.130 0.161
Others 0 – 0 – 0 –
Sex Females −8.08 5.61 <0.0001 −23.38 13.57 <0.0001 −0.133 0.099 0.3865
Males 10.05 5.26 16.61 12.89 −0.116 0.089
Mixed 0 – 0 – 0 –
FP 1 14.68 14.05 0.1397 72.58 37.09 0.1033 0.113 0.172 0.5799
2 −6.50 7.26 8.88 20.52 0.151 0.110
3 7.54 7.56 37.48 21.32 0.122 0.112
>3 0 - 0 - 0 -
SD 2.33 0.36 <0.0001 5.06 0.78 <0.0001 0.014 0.007 0.1075
SD × SD −0.023 0.004 <0.0001 −0.042 0.009 <0.0001 NS NS NS
GS −0.081 0.086 0.3719 −0.124 0.222 0.3521 −0.0003 0.0002 0.1965
GS × GS 0.00004 0.00002 0.0028 0.00008 0.00003 0.0242 −3.08E-8 0.01E-10 0.3983
BM No −13.48 6.84 0.0493 −33.87 15.52 0.0295 −0.027 0.081 0.7370
Yes 0 – 0 – 0 –
Enrichment No −2.00 2.05 0.3297 −4.16 4.36 0.3403 0.006 0.8933
Yes 0 – 0 – 0
DP 1.53 0.26 <0.0001 4.50 0.57 <0.0001 0.006 0.2658
DS No −4.50 2.45 0.0671 −10.89 5.22 0.0375 0.002 0.055 0.9660
Yes 0 – 0 – 0 –
EC No −9.53 7.92 0.2293 0.548 21.27 0.9795 0.314 0.121 0.0095
Yes 0 – 0 – 0 –
MU No −6.59 6.59 0.3175 −26.72 19.40 0.1689 −0.020 0.103 0.8474
Yes 0 – 0 – 0 –
EIA × ED −0.068 0.009 <0.0001 −0.100 0.020 <0.0001 NS NS NS
EIA × Breed Aviagen 0.079 0.114 <0.0001 0.010 0.241 <0.0001 0.005 0.002 0.0002
Aviagen × Cobb Vantress 0 – 0 – 0 –
Cobb Vantress 0.097 0.152 0.257 0.326 0.012 0.003
Group Grimaud −1.07 0.19 −1.65 0.45 0.015 0.004
Others 0 – 0 – 0 –
EIA × SD 0.020 0.004 <0.0001 0.035 0.008 <0.0001 −0.00024 0.00007 0.0005
EIA × DP −0.017 0.010 0.0872 −0.052 0.021 0.0153 0.0006 0.0002 0.0040
SD × GS −0.0019 0.0002 <0.0001 −0.0032 0.0005 <0.0001 9.09E-6 4.11E-6 0.0275
SD × Sex Females −0.086 0.133 <0.0001 0.270 0.286 0.0002 0.007 0.003 0.0432
Males −0.380 0.096 −0.594 0.207 0.004 0.002
Mixed 0 – 0 – 0 –
SD × FP 1 0.483 0.628 <0.0001 −1.06 1.61 <0.0001 NS NS NS
2 −0.280 0.114 −0.657 0.246 NS NS NS
3 −0.425 0.094 −0.950 0.203 NS NS NS
>3 0 – 0 – NS NS NS
SD × DP −0.041 0.014 0.0024 −0.100 0.029 0.0006 −0.0006 0.003 0.0427
SD × EC No 0.957 0.132 <0.0001 1.36 0.30 <0.0001 −0.012 0.003 <0.0001
Yes 0 – 0 – 0 –
GS × Breed Aviagen 0.176 0.071 0.0541 0.349 0.174 0.0537 NS NS NS
Aviagen × Cobb Vantress 0.657 0.291 1.19 0.62 NS NS NS
Cobb Vantress 0.184 0.072 0.378 0.178 NS NS NS
Group Grimaud 0.189 0.109 0.682 0.282 NS NS NS
Others 0 – 0 – NS NS NS
GS × Sex Females 0.002 0.035 <0.0001 0.028 0.088 <0.0001 NS NS NS
Males 0.023 0.035 0.068 0.089 NS NS NS
Mixed 0 – 0 – NS NS NS
GS × BM No 0.365 0.151 0.0161 0.787 0.337 0.0198 NS NS NS
Yes 0 – 0 – NS NS NS
GS × DP −0.005 0.002 0.0208 −0.012 0.005 0.0183 NS NS NS
GS × EC No −0.514 0.090 <0.0001 −1.21 0.21 <0.0001 NS NS NS
Yes 0 – 0 – NS NS NS
RMSE 0.25 0.51 0.01

1ED: duration of the experimental period (d); EIA: experimental initial age (d); FP: feeding phases; SD: stocking density (kg/m2); GS: group size (n); BM: bedding material; DP: duration of the photoperiod (h); DS: divided scotoperiod (h); EC: environmental control; MU: use of vaccines and other medications.