The LayWel project: Welfare implications of changes in production systems for laying hens

World's Poultry Science Journal (Impact Factor: 1.09). 03/2007; 63(01). DOI: 10.1017/S0043933907001328
Source: OAI

ABSTRACT The conditions under which laying hens are kept remain a major animal welfare concern. It is one of the most intensive forms of animal production and the number of animals involved is very high. Widespread public debate has stimulated the call for more animal friendly, alternative systems to barren conventional cages. Directive 1999/74/EC has encouraged technical changes in current systems. Not only have traditional cages been modified (so-called ‘enriched cages’), but also new alternative systems (e.g. aviaries) have been developed. There is an ongoing need to evaluate the actual welfare status of hens in these novel systems including those on commercial farms.The LayWel project, was funded via the European Commission's Sixth Framework Programme and national funding from several EU countries. Its general objective was to produce an evaluation of the welfare of laying hens in various systems, with special focus on enriched cages, and to disseminate the information in all member states of the EU and associated countries. The project took into account pathological, zootechnical, physiological and ethological aspects.A major achievement of the LayWel project was the compilation of a database collecting data from different housing systems and thus enabling data comparison. The project partners recommend that support is given to maintaining the database in the future so that data can be more reliably modelled.As the type of data collected did not often allow a formal statistical analysis the evaluation of welfare was a presentation of risk factors and advantages and disadvantages of various housing systems. Conclusions are that, with the exception of conventional cages, all systems have the potential to provide satisfactory welfare for laying hens. However this potential is not always realised in practice. Among the numerous explanations are management, climate, design, different responses by different genotypes and interacting effects.A second major achievement of the project was the development of feather scoring and integument (skin, head and feet) scoring systems together with comprehensive sets of photographs.It is recommended that the integument scoring systems are widely adopted and used in on-going research. Farms should also routinely and frequently carry out integument scoring to assist in the detection of damaging pecking, which is currently a widespread welfare problem.Within LayWel an on-farm auditing procedure was developed in the form of a manual for self-assessment. The manual first explains what is meant by welfare and outlines the relevance of welfare assessment. It also summarises risks to welfare in the main categories of housing system. The second part contains recording forms, with guidance for assessing hen welfare. These enable regular checks of a range of indicators of laying hen welfare to be carried out systematically. The indicators were chosen to be relevant to hen welfare as well as feasible and reliable to apply in practice.A series of conclusions and recommendations were made on various aspects of housing systems, behaviour, health and mortality and other matters in relation to bird welfare. Full details of these and all other aspects of the LayWel project can be found on The information is also available on CDROM of which copies are freely available on request.

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Available from: Werner Bessei, Sep 27, 2015
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    • "If a covered veranda or a free-range area was present, an approximate representative number within the sample of 50 birds was scored in those areas . Plumage conditions of 5 body parts (neck, back, wings, tail, vent) were scored on an ordinal 4-point scale, adapted from the LayWel project (Tauson et al., 2005b; Blokhuis et al., 2007). For the wings, the wing with the worst plumage condition was scored. "
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    ABSTRACT: Feather pecking and high mortality levels are significant welfare problems in non-cage housing systems for laying hens. The aim of this study was to identify husbandry-related risk factors for feather damage, mortality, and egg laying performance in laying hens housed in the multi-tier non-cage housing systems known as aviaries. Factors tested included type of system flooring, degree of red mite infestation, and access to free-range areas. Information on housing characteristics, management, and performance in Belgian aviaries (N = 47 flocks) were obtained from a questionnaire, farm records, and farm visits. Plumage condition and pecking wounds were scored in 50 randomly selected 60-week-old hens per flock. Associations between plumage condition, wounds, performance, mortality, and possible risk factors were investigated using a linear model with a stepwise model selection procedure. Many flocks exhibited a poor plumage condition and a high prevalence of wounds, with considerable variation between flocks. Better plumage condition was found in wire mesh aviaries (P < 0.001), in aviaries with no red mite infestation (P = 0.004), and in free-range systems (P = 0.011) compared to plastic slatted aviaries, in houses with red mite infestations, and those without a free-range area. Furthermore, hens in aviaries with wire mesh flooring had fewer wounds on the back (P = 0.006) and vent (P = 0.009), reduced mortality (P = 0.003), and a better laying performance (P = 0.013) as compared to hens in aviaries with plastic slatted flooring. Flocks with better feather cover had lower levels of mortality (P < 0.001). Red mite infestations were more common in plastic slatted aviaries (P = 0.043). Other risk factors associated with plumage condition were genotype, number of diet changes, and the presence of nest perches. Wire mesh flooring in particular seems to have several health, welfare, and performance benefits in comparison to plastic slats, possibly related to decreased feather pecking, better hygiene, and fewer red mite infestations. This suggests that adjustments to the aviary housing design may further improve laying hen welfare and performance. © 2015 Poultry Science Association Inc.
    Poultry Science 07/2015; 94(9). DOI:10.3382/ps/pev187 · 1.67 Impact Factor
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    • "The smooth plastic mat located in the scratch area may have been a more desirable surface for egg laying, which would help to explain the number of eggs laid outside of the nest, at least in large cages. Enclosure has also been shown to influence nest site selection and nesting behaviour (Smith et al., 1993; Struelens et al., 2005; Blokhuis et al., 2007), but not due to increased darkness (Woodgush and Murphy, 1970). Hens in our study may have perceived the scratch area in large cages as slightly more enclosed (when compared to the scratch area in small cages) because of the wire partition affixed to the auger. "
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    ABSTRACT: Furnished cages are designed to accommodate behaviour considered important to laying hens, particularly nesting behaviour. Few researchers have studied the degree of competition for nest sites or the extent to which the amount of nest space affects nesting behaviour in large furnished cages. We explored the effect of floor (low 520 cm2/bird, high 750 cm2/bird)/nest space allowance (low 70 cm2/bird, high 100 cm2/bird) and overall cage/nest size (small 20880/2816 cm2; large 41296/5664 cm2) on the nesting behaviour of hens in furnished cages. There were six replicates per size x space allowance combination and four resultant group sizes of 28, 40, 55, and 80. Each cage was equipped with a nest located at one end that was fitted with plastic curtains and plastic mesh floors; a smooth plastic mat intended as a scratch area was located on the opposite cage wall. The location of each egg laid within the cage, oviposition times, pre-laying sitting and agonistic behaviours were recorded at various times during the production year. More eggs were laid in the nest area in small cages (91.7 ± 0.2%) than large (77.2 ± 0.5%; P < 0.001), with no significant effect of space allowance (P = 0.46). Most of the remaining eggs were laid in the scratch area in all treatments. The average peak oviposition time was from 08:00 to 09:00 h (lights on 05:00 h), but the distribution of eggs laid over time differed with nest location (P = 0.02) and cage/nest size (P = 0.02). There were more aggressive pecks (0.087 ± 0.010 vs. 0.045 ± 0.005; P = 0.004) and threats (0.032 ± 0.005 vs. 0.014 ± 0.002; P = 0.02) per bird per 30-min observation in small than large cages with no effect of space allowance (P = 0.236; P = 0.15). More pecks and threats occurred between 08:00 and 08:30 h than the other three time periods, which coincided with the peak oviposition time. Hens in small cages, with low floor and nest space allowance per bird, showed the highest average frequency of agonistic behaviour per bird compared to the other three treatment groups (P = 0.04). Nesting behaviour was mainly affected by cage/nest size but not floor/nest space allowance. Differences in cage design or group size may be factors influencing increased competition for nest space. The birds in the smaller cages appeared to be more willing to aggressively compete to lay their eggs in the curtained nest area while more birds in larger cages chose to lay their eggs in an alternative location. Further behavioural research will be able to determine how best to satisfy nesting motivation of hens housed in large furnished cages.
    Applied Animal Behaviour Science 09/2014; 161(1). DOI:10.1016/j.applanim.2014.08.005 · 1.69 Impact Factor
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    • "However, these production systems can have a variable impact on different aspects of welfare which are often not easily grasped by consumers. For example, even though, free-range hens may have increased behavioural freedom there may be some increased risk of disease and parasitism compared to cage systems (Blokhuis et al., 2007). Different schemes may use scientific evidence, established experience and practical common sense to define resource requirements. "
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    ABSTRACT: Certification schemes that aim to provide an assurance on animal welfare have been developed in many countries but there is no internationally agreed mechanism for recognising the equivalence of animal welfare schemes. The lack of standardisation is a complication in international trade as the lack of clarity may impede demand for products from animals reared according to specified levels of welfare. An important first step is to define a credible best practice framework for animal welfare certification schemes that could apply in any country. Schemes may aim to provide assurance on minimum levels of welfare or may also aim to promote welfare improvement within their scheme membership. It is proposed here that certification schemes wishing to make animal welfare claims could adopt a scheme level continuous improvement approach, as already used in quality and environmental certification schemes, to promote improvement at a farm level. It is suggested that this can be achieved by using the following four generic principles. Firstly the scheme can operate a management system that co-ordinates scheme activities which actively promote improvement in animal welfare within participating farms. This management system should include the following generic steps: plan (establish the objectives including desired outcomes, scheme requirements and monitoring processes), do (implement scheme inspection systems and support structures), check (measure and monitor the process and results) and improve (take action to improve performance). Secondly the scheme should develop progressive resources and outcomes requirements that comply with relevant legislation, encourage the provision of opportunities valued by the animals, promote farm level continuous improvement in important welfare outcomes and require innovation not to compromise welfare goals. Thirdly the scheme should target its assessment and support resources on important welfare concerns. Activities should include assessment of relevant welfare requirements and outcomes, promoting interest amongst farmers in their management, ensuring technical advice is available and insisting on remedial action for those farmers with consistent poor outcomes. Finally by taking an evidence-based, participatory and transparent approach the scheme should also embrace external scrutiny and involvement.
    Trends in Food Science & Technology 06/2014; 37(2). DOI:10.1016/j.tifs.2014.03.009 · 4.65 Impact Factor
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