Severe feather pecking (SFP) is a major animal welfare problem in layers. It results in pain and injuries in the affected animal. It was the aim of this study to gain insight into the actual pecking behavior of laying hens kept on commercial farms with flock sizes common in practice. We observed aggressive pecking and SFP in non-beak-trimmed and beak-trimmed flocks of laying hens and investigated possible influencing factors. The study took place on eight conventional farms in Germany with aviaries, including three farms with a free range and a winter garden, one with a free range and one with a winter garden. Pecking behavior was observed during three observational periods (OPs): OP 1, at the peak of the laying period between the 28th and 33rd week of life; OP 2, in the middle of the laying period between the 42nd and 48th week of life; and OP 3, at the end of the laying period between the 63rd and 68th week of life in one laying period. Videos were analyzed using behavior sampling and continuous recording. We found that SFP occurred in all flocks, but the pecking rate differed significantly between the flocks. SFP correlated positively with the number of hens per square meter of usable area, with statistical significance in the litter area (r = 0.564; p = 0.045). The multivariate analysis revealed that access to a winter garden or free range significantly reduced the SFP rate on perches (p = 0.001). The stocking density (number of birds per usable square meter) had a significant influence on the SPF rate in the nest-box area (p = 0.001). The hybrid line had a significant effect on the SFP rate on perches and in the nest-box area (p = 0.001 each). Lohmann Brown hens in mixed flocks had a higher SFP rate (significant in OP 2) than those in homogeneous flocks, indicating that mixed flocks may be a risk factor for SFP. Lohmann Brown hens pecked significantly less than Dekalb White hens in the litter area (p = 0.010) and in the nest-box area (p = 0.025) and less than Lohmann Selected Leghorn hens in the litter area (p = 0.010). Lohmann Brown and Lohmann Selected Leghorn hens showed increasing SFP rates during the laying period. All hybrid lines had significantly higher SFP rates in the litter area, followed by the nest-box area and perches. These findings emphasize the importance of providing enough litter, litter areas and environmental enrichment. We found a significant positive correlation between aggressive pecking and SFP—in OP 1: rho (Spearman) = 0.580, p < 0.001; OP 2: rho = 0.486, p = 0.002; and OP 3: rho = 0.482, p = 0.002 (n = 39) —indicating that SFP may lead to a higher stress level in the flock. Beak trimming reduced pecking rates but did not entirely prevent SFP. Instead of subjecting chicks to this potentially painful procedure, reasons for SFP should be addressed. In conclusion, our data suggest a positive influence of a lower stocking density and the provision of a winter garden or free range for additional space. The hybrid line had a significant influence on the feather-pecking rate on perches and the nest-box area. Aggressive pecking and severe feather pecking correlated positively. We assume that vigorous and painful AP were an additional stress factor, especially in non-beak-trimmed flocks, leading to more SFP in due course. Beak trimming had a reducing effect on SFP. However, our results showed that non-beak-trimmed flocks could be kept without major outbreaks of SFP.
Various plumage and integument scoring methods are commonly used to deduce the occurrence of severe feather pecking and cannibalism in laying hens. The aim of our study was to provide evidence of correlations between the occurrence of severe feather pecking and our individual plumage scoring system used under practical conditions on commercial farms with non–beak-trimmed and beak-trimmed layers (study I). In second step, we aimed to verify whether the results of the elaborate individual scoring may be predicted with a visual scoring method based on the total body scores of groups of birds (study II). For study I we observed the pecking behavior and performed an individual plumage scoring at the beginning, in the middle, and at the end of a laying period on 8 commercial farms. For study II we performed both an individual and a visual plumage scoring on 49 flocks on 45 farms at the beginning of the laying period and on 43 flocks on 41 farms at the end of the laying period. Spearman's Rho revealed a correlation of the mean feather pecking rate with the total plumage score, the neck–back plumage score, and the total cannibalism score in all observation periods. A high feather pecking rate was correlated with severe plumage damage and the frequent occurrence of skin injuries. We conclude that both the total plumage score and the neck–back plumage score constitute a reliable indicator of the occurrence of severe feather pecking in the flocks assessed in this study. The results of study II suggest that the percental assessment of plumage damage on flock level in 3 categories (“visual score”) leads to a good prognosis of the actual, individually assessed plumage score. Therefore, the application (and documentation) of the visual score on a regular basis can provide a good evaluation of the development of the plumage condition of the flock. The visual score presented in this study is suggested as a suitable instrument for self-evaluation programs on farms.
The assessment of foot pad dermatitis at slaughter is a suitable method to assess and monitor the welfare of broilers. The goals of this study were to define and validate a camera-based score that could identify macroscopic lesions of the foot pads, to identify errors, and to assess possible external factors that could influence the assessment. In the first phase 200 feet of broilers and in the second phase 500 feet were collected at slaughter, assessed visually, hung back into the evisceration line, and assessed by an automatic system. The camera score cut-off values were defined in the first (=calibration) phase. In the second (=validation) phase, the performance of diagnosis for these cut-off values was evaluated, and possible errors in the assessment of reference surface area and foot pad lesions were analyzed. The results showed that, in particular, Macro Scores 0, 2, and 3 could be identified with sufficiently high sensitivity. For Macro Score 1, the sensitivity of diagnosis was not sufficiently high in the two evaluated software versions. The current automatic assessment systems at slaughter could be adjusted to the cut-off values in order to classify foot pad dermatitis lesions. Furthermore, software updates can enhance the performance measures and lower the probability of errors.