Use of conjoint analysis to weight welfare assessment measures for broiler chickens in UK husbandry systems
For the purposes of farm animal welfare assessment, Farm Assurance Schemes and enforcement of animal welfare legislation, a requirement arises for a unitary welfare score which may be the amalgamation of several animal welfare measures. In amalgamating measures, weighting to reflect
the importance of the individual measures for animal welfare is desirable. A study is described in which conjoint analysis was used to collect and evaluate expert opinion to weight a number of welfare assessment measures for the importance of each to broiler welfare in UK husbandry systems.
The statistically combined opinion of the experts consulted revealed the weighting factors of the welfare assessment measures selected, with respect to the importance for bird welfare, to be: 0.26 for mortality levels on the growing unit; 0.24 for the level of leg weakness; 0.16 for the level
of hock burn; 0.14 for stocking density; 0.10 for enrichment provision; and, 0.10 for the level of emergency provision. Criteria for selection of welfare assessment measures for use in the field, and level of agreement between experts consulted for the study, are discussed. It is concluded
that weightings of welfare assessment measures by expert opinion, using conjoint analysis, might be used in the construction of a welfare index for assessment of broiler welfare on-farm. Such an index should not be considered as a 'gold standard' for welfare measurement but as an evolving
standard for welfare assessment, based on current knowledge.