Standard techniques for assessing plumage damage to hens from feather pecking typically require capture and handling. Handling of individual birds for plumage assessment is relatively easy in experimental studies; however, close inspection of individual birds in commercial flocks is less feasible because catching birds is difficult, may compromise bird welfare and affect egg production. The aim of this study was to assess a non-intrusive method for scoring plumage damage in a commercial free-ranging flock of laying hens. Plumage damage was scored within a 2 m distance of the birds, without capture or handling, using a 5-point scale for 5 body regions. The feather scores, recorded at a distance, by two independent scorers were compared (distance scores), and were then compared with feather scores recorded by a scorer who caught and handled the birds to examine the plumage damage closely (capture scores). There was a significant and positive correlation between the distance scores and the capture scores, and the mean correlation coefficient for all plumage score traits was 0.89. There was also a significant and positive correlation between scorers, and the mean correlation coefficient for all plumage score traits was 0.84. The standard deviation of the residual mean difference between scorers and between methods was less than 1 point for individual body regions and less than 1.5 points for the total body score. Large variation in feather damage within a flock and small sample size increased the standard error of the mean total feather score. When feather damage variation within flocks is low (ie little observed feather damage), the current industry standard of scoring a sample of 100 birds is likely to provide a reliable estimate of flock feather damage; however, when there is large variation within birds of a flock (ie considerable observed feather damage) ≥200 birds should be inspected to accurately monitor changes in plumage condition. The non-intrusive method of feather scoring described in this paper may be useful for commercial-scale feather pecking studies or for farmers who need to assess the plumage damage of their flocks reliably, quickly and with minimal disturbance or stress to the birds.

Injurious feather-pecking in non-cage systems is a serious economic and welfare concern for the egg-producing industry. This study presents results from data of over 1,000 flocks from producers who supplied free-range eggs to McDonald's Restaurants Ltd UK between 2008 and 2013. These producers had a minimum 5% of the outdoor range planted in trees. We investigated the correlation between the plumage damage of end-of-lay hens with i) proportion of the total range planted with trees and ii) proportion of canopy cover within tree-planted areas. As tree canopy developed over the study period, we also investigated whether there were any changes in end-of-lay plumage-damage scores within farms, with year over the five years. There was a negative correlation between canopy cover and plumage damage at the end of lay, ie less canopy cover within tree-planted areas resulted in significantly worse plumage damage at the end of lay. There was no correlation between the amount of range planted and plumage damage at the end of lay. These results support the notion that it is the degree of shade and shelter (ie quality of cover) that is important to the hens rather than the absolute area. We did not find any association between year and end-of-lay plumage-damage scores. Due to commercial changes in supply, the proportion of farms providing data for ≥ 3 years was small, thereby limiting the data set with which to compare individual farms’ plumage-damage scores. It is hoped the relationship between year and plumage-damage score will be reexamined in a future study.

Feather eating has been associated with feather pecking, which continues to pose economic and welfare problems in egg production. Knowledge on feather eating is limited and studies of feather eating in commercial flocks of laying hens have not been performed previously. Therefore, the main objective was to investigate feather eating and its association with plumage damage and floor feather characteristics in commercial flocks of layers in barn and organic production systems. The study was performed in 13 flocks of barn layers and 17 flocks of organic layers. Each flock was visited at around 32 and 62 weeks of age. During both visits, the plumage condition was assessed and the density of floor feathers recorded. In week 62, droppings and floor feathers were collected. Droppings were examined for presence of feather content, whereas length, downiness and pecking damage were recorded for each floor feather. In week 62, a higher prevalence of hens with poor plumage condition was found in barn (22.2%) compared with organic production systems (7.4%; P<0.001), but the prevalence of droppings with feather content did not differ between the two production systems (8.5% in barn v. 4.3% in organic; P=0.99). Our hypothesis about a positive correlation between feather eating and plumage damage was not supported as no correlation was found between the prevalence of poor plumage condition and the prevalence of droppings with feather content. However, the prevalence of pecking damaged floor feathers was positively correlated both with prevalence of droppings with feather content (P<0.05) and poor plumage condition (P<0.01), indicating a possible association between feather eating and feather pecking. In conclusion, it was confirmed that feather eating occurs on-farm, but feather eating was only found to be positively correlated to the number of floor feathers with pecking damage and not as expected to the prevalence of plumage damage. More research is needed into the sources from where feathers are selected for ingestion, that is, whether they are picked from the floor litter, plucked directly from other hens or dislodged during preening of own feathers.

Severe feather-pecking (SFP) persists as a highly prevalent and detrimental behavioural problem in laying hens (Gallus gallus domesticus) worldwide. The present experiment investigated the association between feather-eating and plumage damage, a consequence of SFP, in groups of free-range, ISA Brown laying hens. Single feathers were placed on the floor of the home pens. Feathers were sourced from seven different birds. A total of 50 birds in six pens with extensive plumage damage were compared with birds in six control pens with little plumage damage at 41 to 43 weeks of age (n=12 pens, 600 hens). Birds in pens with extensive plumage damage ingested more feathers (F=8.1, DF=1, 8, P=0.02), and also showed shorter latencies to peck at (χ2=54.5, DF=1, P<0.001), and ingest feathers (χ2=55.6, DF=1, P<0.001). Birds ingested feathers from a bird in the free-range facility, in which the testing took place, more quickly than from a bird housed in a separate cage facility (χ2 = 39.0, DF=6, P<0.001). A second experiment investigated the predictive relationship between feather-eating and plumage damage. Feathers were presented to 16 pens of 50 pullets prior to the development of plumage damage, at 15 weeks of age, and then to the same hens after plumage damage had become prominent, at 40 weeks of age. Birds had a higher probability of ingesting feathers (F=142.0, DF=1, 231, P<0.001), pecked feathers more times (F=11.24, DF=1, 239, P<0.001), and also pecked (χ2 = 127.3, DF=1, P<0.001) and ingested (χ2=189.3, DF=1, P<0.001) the feathers more quickly at 40 than 15 weeks of age. There was a trend for an interaction, where birds pecked feathers from the rump more times than feathers from the back at 40 weeks of age (F=3.46, DF=1, 237, P=0.06). However, a lack of variability in plumage damage between pens in this experiment precluded investigation of the predictive relationship. The results from the present study confirm the association between feather-eating and plumage damage, and suggest that birds may prefer feathers from particular body areas and from particular hens. Future experiments should focus on elucidating whether feather-eating may act as a predictor of SFP.

Severe feather-pecking (SFP), a particularly injurious behaviour in laying hens (Gallus gallus domesticus), is thought to be negatively correlated with range use in free-range systems. In turn, range use is thought to be inversely associated with fearfulness, where fearful birds may be less likely to venture outside. However, very few experiments have investigated the proposed association between range use and fearfulness. This experiment investigated associations between range use (time spent outside), fearfulness, plumage damage, and BW. Two pens of 50 ISA Brown laying hens (n=100) were fitted with radio frequency identification (RFID) transponders (contained within silicone leg rings) at 26 weeks of age. Data were then collected over 13 days. A total of 95% of birds accessed the outdoor run more than once per day. Birds spent an average duration of 6.1 h outside each day over 11 visits per bird per day (51.5 min per visit). The top 15 and bottom 15 range users (n=30), as determined by the total time spent on the range over 13 days, were selected for study. These birds were tonic immobility (TI) tested at the end of the trial and were feather-scored and weighed after TI testing. Birds with longer TI durations spent less time outside (P=0.01). Plumage damage was not associated with range use (P=0.68). The small group sizes used in this experiment may have been conducive to the high numbers of birds utilising the outdoor range area. The RFID technology collected a large amount of data on range access in the tagged birds, and provides a potential means for quantitatively assessing range access in laying hens. The present findings indicate a negative association between fearfulness and range use. However, the proposed negative association between plumage damage and range use was not supported. The relationships between range use, fearfulness, and SFP warrant further research.