## 3 Results
### Risk Factors for Plumage Damage in the Laying Period
The variable'rearing' was used for the model, which refers to the mean plumage condition of the flock during the rearing period. [PERSON]'s \(V\) showed a medium-to-large effect of the plumage condition in the rearing period on severe plumage damage in the laying period for all visits (LV1: 0.443, LV2: 0.608, LV3: 0.451), which reached a significant level for LV2 (\(p=0.031\)). Laying hens that grew up in rearing flocks with no plumage damage developed severe plumage damage later in life, and to a lesser extent than laying hens growing up in rearing flocks with plumage damage. The model for both laying periods for LV1 described 49.8% (corrected 27.5%) of the variance of the dependent variable'severe plumage damage'. The explanation of variance of the model was not significant. There were significant effects of the variables 'free range', 'flitter quality', and 'enrichment'. For LV2, the model explained 67.6% (corrected 53.9%) of the variance of the dependent variable'severe plumage damage'. The explanation of variance for the model was significant (\(p=0.002\)). There were significant effects of the variables'rearing' and 'flitter quality'. For LV3, the model explained 72.2% (corrected 59.8%) of the variance of the dependent variable'severe plumage damage'. The variables'rearing', 'flitter quality', and 'free range' were significant (Table 7). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Variable** & **LP1: LV1** & **LP1: LV2** & **LP1: LV3** & **LP2: LV1** & **LP2: LV2** & **LP2: LV3** \\ \hline \multirow{2}{*}{Feeding trough/hen (cm)} & rho = 0.223 & rho = \(-0.137\), & rho = \(0.007\), & rho = \(0.155\), & rho = \(0.127\), & rho = \(0.286\), \\  & \(p=0.263\) & \(p=0.454\) & \(p=0.967\) & \(p=0.489\) & \(p=0.541\) & \(p=0.178\) \\ \hline \multirow{2}{*}{Hens/drinking nipple} & rho = 0.125, & rho = 0.167, & rho = 0.222, & rho = \(-0.124\), & rho = \(-0.380\), & rho = \(-0.338\), \\  & \(p=0.527\) & \(p=0.360\) & \(p=0.216\) & \(p=0.580\) & \(p=0.066\) & \(p=0.111\) \\ \hline \multirow{2}{*}{Litter quality} & rho = **0.083 \({}^{*}\)**, & rho = \(-0.046\), & rho = 0.098, & rho = \(-0.377\), & **rho = \(-0.523\) \({}^{*}\)**, & rho = \(-0.418\), \\  & \(p=0.022\) & \(p=0.216\) & \(p=0.008\) & \(p=0.114\) & **p = \(0.018\)** & \(p=0.070\) \\ \hline \multirow{2}{*}{Litter depth} & rho = **0.108 \({}^{*}\)**, & rho = **0.286 \({}^{*}\)**, & rho = \(-0.039\), & rho = \(-0.093\), & rho = \(0.023\), & rho = \(0.065\), \\  & \(p=0.002\) & \(p<0.001\) & \(p=0.271\) & \(p=0.678\) & \(p=0.911\) & \(p=0.870\) \\ \hline \hline \end{tabular}
\end{table} 
Table 6: _Cont._ \begin{table}
\begin{tabular}{c c c} \hline \hline
**Factor** & **Significance (\(p\))** & **Partial Eta-Squared** \\ \hline
**LV1** & & \\ \hline Corrected model & 0.075 & 0.498 \\ Constant term & 0.492 & 0.027 \\
**Free range** & **0.006 \({}^{*}\)** & **0.346** \\
**Litter quality** & **0.027 \({}^{*}\)** & **0.242** \\
**Enrichment** & **0.036 \({}^{*}\)** & **0.222** \\
**Rearing** & 0.562 & 0.062 \\ Mixed flock & 0.282 & 0.064 \\ Perch/laying hen (cm) & 0.739 & 0.006 \\ Litter depth & 0.994 & 0.000 \\ \hline LV2 & & \\ \hline Corrected model & 0.002 & 0.676 \\ Constant term & 0.023 & 0.244 \\
**Rearing** & **0.004 \({}^{*}\)** & **0.443** \\
**Litter quality** & **0.021 \({}^{*}\)** & **0.248** \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Univariate multifactorial analysis of variance for the dependent variable ‘severe plumage damage’ for both laying periods. \({}^{*}=\) Significant effect (\(p\leq 0.05\)). LV = laying visit.