Development of a Scoring System to Assess Feather Damage in Canadian Laying Hen Flocks

SIMPLE SUMMARY: Feather damage is a continuous welfare challenge in the management of egg-laying hens. Canada is currently transitioning from conventional cages to alternative housing systems, where the risk of feather damage may increase due to larger group sizes. This change increases the need for continued and reliable assessment of flock feather condition, for which Canada does not have a standard method. Within this study, a feather damage scoring system and visual scoring guide were developed, with the ultimate goal of streamlining and increasing plumage assessment of laying flocks by farmers on Canadian commercial farms. Two differing feather scoring systems (LayWel and AssureWel) were compared based on user-friendliness and reliability. The AssureWel scoring system was easiest to use and achieved the most consistent outcomes among scorers for the back area of the body. This informed the design of a modified version with scoring levels from 0 to 2 for a sample of 50 birds per flock, along with an informational, visual guide for farmers. Training of farmers to use this simplified scoring system under commercial conditions can provide a benchmarking tool for feather damage levels, as well as a way to measure the success of management strategies to prevent and control feather damage. ABSTRACT: Feather damage (FD) due to feather pecking behavior is an ongoing welfare concern among commercial egg-laying hens. Canada’s current transition from conventional cage housing to alternative housing systems, where FD can spread easily within large flocks, underlines the need for frequent and accurate assessment of plumage condition. A standardized methodology for assessing FD in Canada does not yet exist. To improve FD assessment on commercial farms, a FD scoring system and visual scoring guide for farmers were developed. Two existing plumage scoring systems, LayWel and AssureWel, which differ in level of detail and bird handling, were assessed for ease of use, and intra- and inter-observer reliability. Practical application of the AssureWel scoring system was greatest, with strong intra- and inter-observer reliability for the back region of the body (weighted kappa = 0.88 for both measures) in small-scale flocks. This informed the creation of a modified version of the AssureWel system, which included three scoring levels and the visual assessment of 50 birds per flock. An accompanying guide was developed including sampling instructions and depictions of the scoring scheme, both written and visual. This simplified scoring system can serve as a benchmarking tool for FD prevalence, and can allow for future effectiveness assessments of management strategies to prevent and control FD; however, farmers should be trained to apply this system under commercial conditions.