It is extremely difficult to carry out an assessment of welfare in an entirely objective manner. The choice of welfare indicators, as well as the assignment of relative weightings to these indicators, both involve a certain degree of subjectivity. The aim of this study was to create a possible method of dealing with this subjectivity, using the opinions of groups of experts to increase the consensus for a protocol for the on-farm assessment of laying-hen welfare. The selection of the 17 separate welfare indicators was based both on a questionnaire submitted to 18 international poultry welfare experts and on the practical feasibility of collecting the respective data during a one-day farm visit. Subsequently, a second group of 13 experts was asked to assign relative weightings to the welfare indicators in this protocol. This assessment was carried out twice, once with and once without provision of detailed information on the welfare indicators. When detailed information was provided, the weightings assigned to the welfare indicators were generally lower than when no detailed information was provided. In conclusion, subjectivity regarding the choice of welfare indicators and the assignment of their relative weightings, can be dealt with and made transparent by seeking consensus among experts. Although the choice of experts, the methodology for extracting consensus data, and the nature and amount of information on the welfare indicators that should be provided, are likely to benefit from further refinement, the data presented in this study should be valuable for the development and application of formalised protocols for an integrated assessment of the welfare of laying hens, on-farm.

A review is presented of results from research and commercial production of two alternative keeping systems – furnished cages and aviary systems. These systems have gradually evolved through criticism of conventional cage keeping of layers, mainly in North Western Europe, due to the lack of possibilities for birds to perform natural behaviours and to restricted space. They provide birds with nests to lay eggs in, perches to rest on, and litter material to manipulate and dust-bathe in. Experience and development of the aviary are longer than that of furnished cages, the latter existing in wide spread commercial production only in Sweden as yet. However, according to a new EU-directive in 1999, conventional cages may not be used as a new investment from 2003 and not at all from 2012. Birds in both systems may produce well but the aviaries are less predictable due to irregular outbreaks of flock cannibalism, especially in non beak-trimmed medium heavy brown birds, despite offering the birds litter and plenty of space. The furnished cages try to combine advantages of small group size in cages and reduce disadvantages of poor air condition, and sometimes inferior hygiene, in floor-kept hens. They are still subjected to extensive improvements in details of design e.g. to enhance egg quality. Hence, results may vary considerably between models. In order to maintain a stable social order it is probably vital to retain a moderate group size in furnished cages.