The welfare of laying hens in conventional cages and alternative systems: first steps towards a quantitative comparison

Egg producer attitudes and expectations regarding the transition to cage-free production: a mixed-methods approach

Several cage-free egg mandates and retailer pledge deadlines are set to take effect in January 2026. Yet it is unknown whether producers can transition to cage-free production at a rate commensurate with these goals. This study uses qualitative and quantitative data from 2 U.S. egg producer surveys to evaluate the operational activities of conventional and cage-free facilities, identify market challenges, and assess the expected transition timeline. Across both studies, producers indicated higher fixed and variable costs in cage-free housing systems, with capital and labor being 2 of the central drivers of the cost increase. While several producers are willing to adopt cage-free production, they are hesitant to view the market shift as an opportunity. Among the most commonly cited barriers are limited customer demand, high capital costs, and a contradiction to environmental sustainability and food security efforts. With the current challenges, respondents are skeptical that the industry will meet the January 2026 voluntary pledge deadlines. The results from this study offer a holistic view of the potential ramifications of the cage-free transition on the egg market and can be used to inform marketing strategies and policy discussions.

A Comparison of the Plumage Condition of Three Egg-Laying Poultry Genotypes Housed in Non-Cage Systems

The study covered a total of 810 hens in 3 groups (housing systems) of 270 hens each. The plumage condition of laying hens raised in various types of alternative housing systems, i.e., in deep litter (B), free-range (FR), and organic systems (O), was assessed at 20, 36, and 56 weeks of age. The indoor stocking density was 6 hens/m2. The study included hens of the native Green-legged Partridge breed (Z-11), Rhode Island Red (R-11) hens covered by a genetic resource protection program, and hybrids of Hy-Line Brown. The plumage of the head, neck, back, tail, and abdomen was assessed on a 5-point scale. The assessment of individual hens' plumage was calculated as the sum of the scores of the head, neck, back, tail and abdomen and could range from 0 (no cover) to 20 points (full plumage). The type of alternative housing system implemented and the age of the laying hens had an effect on the plumage status of all body parts assessed (p < 0.05), while the genotype had an effect on the condition of the neck, back, and tail plumage (p < 0.05). In both the FR and O systems, the plumage status was similar and superior to that in B (p < 0.05). As the age of the birds increased, the condition of the hens' plumage deteriorated. The better state of the plumage in FR and O than in B may indicate improved levels of welfare in housing systems with access to outside runs.

End of lay postmortem findings in aviary housed laying hens

Good health and low mortality are constitutive elements of good animal welfare. In laying hens, mortality and pathological findings are usually reported as cumulative proportions from onset of lay to culling. However, knowledge of pathological lesions and causes of death specifically toward the end of the production period are scarce. This study aimed to investigate the occurrence of postmortem lesions and tentative causes of death in non-beak trimmed, end of lay hens, housed in multitiered aviary systems. A convenience sample of 48 flocks was recruited. In each flock, layers dead between wk 65 and 70 were necropsied in the field. In total, 482 layers were subjected to postmortem examination. The 4 most common pathological lesions were keel bone fracture (KBF) (92%), fatty liver (42%), emaciation (23%), and salpingitis (22%). Apart from keel bone fracture, the relative frequency of the pathological lesions variated between flocks, indicating that flock is an important factor. Common tentative causes of death were salpingitis (18%) and fatty liver hemorrhagic syndrome (FLHS) (13%). This study sheds light on health challenges aviary housed layers are facing end of lay, which is crucial knowledge in the development of preventive measures to secure good health and welfare.

Influence of Increased Freedom of Movement on Welfare and Egg Laying Pattern of Hens Kept in Aviaries

This work investigates the effects of structural modifications on the welfare level and laying patterns of hens in a three-tier commercial aviary system. Four experimental groups were used: C (control, housed in a traditional aviary); LM (longitudinal movement, in which internal partitions were removed); VM (vertical movement, in which ramps were installed); and FM (freedom of movement, both LM and VM modifications). Hens showed worse body condition scores (p < 0.05) in all the modified aviaries, while plumage condition was improved in FM but worsened in VM (p < 0.05). No significant effect was observed on egg deposition patterns, egg quality or keel bone damage. When ramps were available (VM and FM groups), hens reduced the number of flights and increased the number of walks from 0.52 to 7.7% of the displacements on average (p < 0.05). Apart from some feather pecking concerns in VM (likely due to overcrowding in some favourite aviary areas), LM and FM seemed to facilitate animal movement and promote species−specific behaviour. It is concluded that hen welfare in aviary systems can be improved by means of tailored structural modifications. Producers may therefore adopt some of these modifications (providing ramps and/or removing vertical barriers) to enhance the welfare of hens.

Types and clinical presentation of damaging behaviour - feather pecking and cannibalism in birds

Behavioural disorders, including feather pecking and cannibalism, are a common problem in both domestic and wild birds. The consequences of this behaviour on welfare of birds incur serious economic losses. Pecking behaviour in birds is either normal or injurious. The type of normal pecking behaviour includes non-aggressive feather pecking – allopreening and autopreening. Aggressive feather pecking aimed at maintenance and establishment of hierarchy in the flock is not associated to feathering damage. Injurious pecking causes damage of individual feathers and of feathering as a whole. Two clinical presentations of feather pecking are known in birds. The gentle feather pecking causes minimum damage; it is further divided into normal and stereotyped with bouts; it could however evolve into severe feather pecking manifested with severe pecking, pulling and removal, even consumption of feathers of the victim, which experiences pain. Severe feather pecking results in bleeding from feather follicle, deterioration of plumage and appearance of denuded areas on victim’s body. Prolonged feather pecking leads to tissue damage and consequently, cannibalism. The nume­rous clinical presentations of the latter include pecking of the back, abdomen, neck and wings. Vent pecking and abdominal pecking incur important losses especially during egg-laying. In young birds, pulling and pecking of toes of legs is encountered. All forms of cannibalistic pecking increase morta­lity rates in birds. Transition of various pecking types from one into another could be seen, while the difference between gentle, severe feather pecking and cannibalism is not always distinct.

Effect of different rearing system on eggs production, hatchability, and offspring quality in layer breeders

This study analyzed the influence of an aviary system, in comparison with battery cages, on rearing and reproduction of parent-stock (PS) laying-type chickens. ISA Brown PS chicks were reared for 16 wk in battery cages or in an aviary system. Chickens reared in cages were kept there throughout the rearing period, whereas those reared in the aviary were released after 7 wk. The remaining housing conditions were similar in cages and the aviary. Body weight (BW, g), feed intake (FI, g/birds/d), and mortality (%) of birds were monitored during rearing. After the rearing period, the chickens were transferred to 4 litter poultry houses: flock C (in cages) to poultry houses C1 and C2 (total: 2,076 cockerels and 20,450 pullets); flock A (in aviary) to poultry houses A1 and A2 (total: 1,542 cockerels and 16,962 pullets). During the period of reproduction (48 wk), egg production (%), hatching egg production (%), waste egg (%) and litter egg production (%), feed conversion ratio (FCR, g) and water intake (mL) per laid egg, hatching egg, and hatched chick, mortality (week/%), and BW at 17 wk and after reaching 50% laying performance were monitored. Furthermore, during incubation, fertilization rate (%), hatchability (%), and chick quality were recorded. The results showed that aviary rearing was associated with lower FI and higher mortality of chicks up to 16 wk of age. The following effects were also observed for aviary rearing during reproduction: the average egg and hatching egg production were higher, while waste and litter egg production were lower; FCR per laid egg, hatching egg, and the number of hatched chicks were poorer; and water intake for the production of 1 hatching egg and 1 hatched chick was lower. In the case of flocks A, higher mortality and BW at 17 wk of age were recorded for both sexes. They were characterized by higher relative egg fertilization, but lower hatchability due to the higher share of unhatched eggs. No influence of PS flock rearing system on chick quality was observed. The obtained results indicate that the aviary rearing system can be recommended for PS laying-type flocks. However, future research should consider the impact of a different diet having higher energy concentration on PS flocks reared in aviaries and develop methods for counteracting higher mortality in these systems. This is particularly significant for roosters because too few roosters in flock may contribute to lower egg fertilization and higher embryonic mortality.

Laying hen mortality in different indoor housing systems: a meta-analysis of data from commercial farms in 16 countries

Societal concern with the welfare of egg laying hens housed in conventional cages is fostering a transition towards cage-free systems in many countries. However, although cage-free facilities enable hens to move freely and express natural behaviours, concerns have also been raised over the possibility that cage-free flocks experience higher mortality, potentially compromising some aspects of their welfare. To investigate this possibility, we conducted a large meta-analysis of laying hen mortality in conventional cages, furnished cages and cage-free aviaries using data from 6040 commercial flocks and 176 million hens from 16 countries. We show that except for conventional cages, mortality gradually drops as experience with each system builds up: since 2000, each year of experience with cage-free aviaries was associated with a 0.35–0.65% average drop in cumulative mortality, with no differences in mortality between caged and cage-free systems in more recent years. As management knowledge evolves and genetics are optimized, new producers transitioning to cage-free housing may experience even faster rates of decline. Our results speak against the notion that mortality is inherently higher in cage-free production and illustrate the importance of considering the degree of maturity of production systems in any investigations of farm animal health, behaviour and welfare.

A meta-analysis on the effect of environmental enrichment on feather pecking and feather damage in laying hens

Feather pecking (FP) is a significant issue in laying hens, which impacts societal acceptance of poultry farming, farm productivity, and bird welfare. Environmental enrichment-modifications of the environment to stimulate biological functioning and psychological well-being of animals-is one management strategy farmers can use to mitigate FP. However, inconsistent results of environmental enrichment are reported across studies questioning its value. A meta-analysis was used to determine the effect of environmental enrichment on FP and feather damage (FD) in laying hens. A systematic review of published literature from 4 databases resulted in 23 publications that met inclusion criteria. Feather pecking and FD outcomes were standardized between studies using different scoring systems. Driving variables included the presence of enrichment, production period when the enrichment started, housing type, beak trimming, bird strain, and age of the birds when FP and FD was measured. Considering the experiment as a random effect, linear mixed model analysis was used in a 2-step approach, whereby variables with a P < 0.30 in univariate analysis were included within the subsequent multivariate analysis. Variables with P < 0.05 in the multivariate analysis were retained in the final models. Model selection and evaluation were based on corrected Akaike information criteria, the root mean square prediction errors, and concordance correlation coefficients. A higher frequency of FP was observed in flocks lacking enrichment (P < 0.001), with increased age (P = 0.001), and in cage housing systems (P = 0.002). Similarly, FD increased in flocks lacking enrichment (P = 0.018), with increased age (P < 0.001), in the absence of beak trimming (P = 0.001) and in cage housing systems (P = 0.042). This meta-analysis confirmed the effectiveness of environmental enrichment in reducing FP and FD. Nevertheless, the modest ability of enrichment to dampen FD (-0.14 ± 0.06, 1-4 scale) suggests that other management strategies must be implemented in conjunction with environmental enrichment to successfully manage FP and resulting FD.

Reproductive performance and quality of offsprings of parent stock of layer hens after rearing in open and closed aviary system

In this study, we analyzed the parent stock of ISA Brown hens reared in closed and open aviary (CA and OA, respectively) sections with regard to the productive performance of hens, hatchability, and quality of chicks. The flocks were reared (1,570 cocks and 17,515 hens) for 16 wk in a three-level aviary system. On the 7th wk of rearing, half of the birds (OA group of birds) were allowed to leave the section and use half of the area of the poultry house and to use all levels. The remaining half of the birds were kept in the CA section for the entire duration of rearing. After the duration of rearing, the birds were moved to 2 neighboring production poultry houses (OA = 680 cocks and 8,126 hens; CA = 685 cocks and 8,133 hens). Reproduction was performed in a litter system in accordance with the norms for parent stock of laying hens. During the production cycle (53 wk), laying performance, feed conversion ratio, water consumption, and mortality were analyzed. On 27th, 37th, and 49th wk of production, the following analysis was performed: rate of fertilization (%), rate of hatching (%), and quality of chick. In accordance with the results, birds in OA flock required less amount of feed (P < 0.001) and water (P = 0.020) to produce a laid egg, a hatching egg (respectively: P < 0.001; P = 0.009), and a chick (both P < 0.001) in comparison with the birds in CA flock. In addition, a lower number of litter eggs were found in the OA flock (P < 0.001). Mean laying production, production of hatching eggs, and number of waste eggs did not depend on the flock rearing system (P > 0.05); however, a combined analysis of all these parameters using multivariate analysis of variance demonstrated a better (P < 0.001) result for OA flock than that of CA flock. Rate of fertilization, rate of hatching, and quality of chicks did not depend on the flock rearing system (P > 0.05). In summary, it is possible to rear parent ISA Brown hens in open sections of aviary system without the fear of subsequent deterioration of indicators of future egg production.

Managing Free-Range Laying Hens-Part B: Early Range Users Have More Pathology Findings at the End of Lay but Have a Significantly Higher Chance of Survival-An Indicative Study

Simple Summary

Free-range facilities may present a biosecurity risk in some situations, but range use has also been associated with better hen welfare. We investigated the association between early-life range use (when hens were 18–21 weeks of age) and hen survival during the entire housing period as well as various health and welfare parameters at 74 weeks of age. Hens that preferred to use the range at early life were three times more likely to survive. Early range users were also 1.6 times more likely to become infected with gastrointestinal nematodes and showed significantly more frequent signs indicating spotty liver disease. Hens that preferred to stay in the shed during early life had a higher prevalence of Fatty Liver Syndrome and significantly less feather cover. In conclusion, hens that do not range during early life may benefit from additional management strategies to increase their likelihood of survival. Further investigations under controlled environmental conditions are warranted to quantify further the observed effects.

Abstract

While free-range laying hens frequently experience health and welfare challenges, the contribution of range use towards these risks are largely unknown. The aim of this pilot study was to investigate the survival, health and welfare of commercial free-range laying hens and explore the association with early range use. Range use of 9375 Lohmann Brown hens housed within five flocks was assessed during 18–21 weeks of age and individual hens were classified as “rangers” (frequent range users), “roamers” (intermittent range users), and “stayers” (rare/no range users) were then subject to necropsy at 74 weeks of age. Rangers and roamers were three times and 2.4 times more likely to survive than stayers, respectively (p = 0.001). Overall, rangers had significantly better feather cover and more lesions associated with spotty liver diseases compared to roamers and stayers (p = 0.001). Similarly, rangers and roamers had a higher prevalence of A. galli infection and less frequent signs of fatty liver syndrome compared to stayers. Rangers had a higher proportion of hens with full ovary follicle production compared to stayers and roamers (p = 0.035). This information is highly relevant to consider the targeted support of different flock subpopulations to improve hen health and welfare, directly affecting farm profitability. Further research on other farms is warranted to investigate the transferability of the observed results.

Managing Free-Range Laying Hens-Part A: Frequent and Non-Frequent Range Users Differ in Laying Performance but Not Egg Quality

Simple Summary

Free-range laying hens are allowed to roam around and exhibit their desired behaviours including usage of the outdoor range. Consequently, flock sub-populations of high-range users (“rangers”) and low-range users (“stayers”) appear. The subpopulation effect on egg production and egg quality has not been studied to date. Rangers were more consistent in their range use, while stayers increased their range use over time. Rangers came into lay earlier compared to the stayers but their egg production dropped during mid-lay until the end of lay when they were outperformed by the stayers. The flock sub-populations did not differ in their egg quality during the production period. These findings are of relevance to egg producers, as it allows them to manage their flock knowing that they can encourage them to range/stay in the shed without compromising egg quality, including off-grade eggs. In the future, it would be interesting to investigate if increased egg performance was triggered by the more frequent range usage.

Abstract

Little is known about the impact of ranging on laying performance and egg quality of free-range hens. The aim of this study was to characterise egg production of commercial free-range laying hen sub-populations of low-, moderate- and high-range use at an early age. A total of five flocks with 40,000 hens/flock were investigated where 1875 hens/flock were randomly selected at 16 weeks of age, monitored for their range use and subsequently grouped into “stayers” (the 20% of hens that spent the least time on the range), “roamers” (the 20% of the hens that used the range more than stayers but less than rangers) and “rangers” (the 60% of the hens that spent the most time on the range). Eggs from the individual groups were collected in 10-weekly intervals until hens were 72 weeks of age, commercially graded and tested for several quality parameters. Significant differences were noted for hen-day production. For example, at 22 weeks of age, rangers enjoyed a laying rate of 88.0% ± 1.1%, while stayers performed at 78.2% ± 1.9% but at 72 weeks of age egg production of rangers was 85.1% ± 0.9% and of stayers was 95.5% ± 0.9% (p < 0.05). Range use was of minor importance to the egg quality.

Risk factors associated with keel bone and foot pad disorders in laying hens housed in aviary systems

Aviary systems for laying hens offer space and opportunities to perform natural behaviors. However, hen welfare can be impaired due to increased risk for keel bone and foot pad disorders in those systems. This cross-sectional study (N = 47 flocks) aimed to assess prevalences of keel bone and foot pad disorders in laying hens housed in aviaries in Belgium to identify risk factors for these disorders and their relation to egg production. Information on housing characteristics and egg production were obtained through questionnaire-based interviews, farm records, and measurements in the henhouse. Keel bone (wounds, hematomas, fractures, deviations) and foot pad disorders (dermatitis, hyperkeratosis) were assessed in 50 randomly selected 60-week-old laying hens per flock. A linear model with stepwise selection procedure was used to investigate associations between risk factors, production parameters, and the keel bone and foot pad disorders. The flock mean prevalences were: hematomas 41.2%, wounds 17.6%, fractures 82.5%, deviations 58.9%, hyperkeratosis 42.0%, dermatitis 27.6%, and bumble foot 1.2%. Identified risk factors for keel bone disorders were aviary type (row vs. portal), tier flooring material (wire mesh vs. plastic slats), corridor width, nest box perch, and hybrid. Identified risk factors for foot pad disorders were aviary type (row vs. portal), free-range, and hybrid. Percentage of second-quality eggs was negatively associated with keel bone deviations (P = 0.029) at the flock level. Keel bone and foot pad disorders were alarmingly high in aviary housing. The identification of various risk factors suggests improvements to aviary systems may lead to better welfare of laying hens.

Relationship between plasma and tissue corticosterone in laying hens (Gallus gallus domesticus): implications for stress physiology and animal welfare

This study directly compared the dynamics of change in plasma corticosterone concentration with the dynamics of change in tissue corticosterone concentration in laying hens. In concert, we measured the rate of gluconeogenesis, glycogenesis, and glycolysis in the liver, kidney, skeletal muscle, and heart. We evaluated these changes acutely, over 3 h in response to an adrenocorticotropic hormone (ACTH) injection, and chronically, over 24 h in response to food and water deprivation. In response to ACTH injection, there was a significant (P < 0.05) increase in plasma corticosterone concentration and a parallel significant increase in corticosterone concentration in the skeletal muscle, kidney, and heart. However, the change in corticosterone concentration in the liver did not parallel the plasma, at times it was greater than the plasma, and there was a second significant increase (P < 0.05) in corticosterone concentration in the liver after 180 min. Under these conditions, the rate of gluconeogenesis in the liver decreased and the rate of glycogenesis increased. In contrast, after 12 h and 24 h of food and water deprivation plasma corticosterone concentration was increased, and this was paralleled by increased corticosterone concentration in the liver, an increase in the rate of gluconeogenesis and a decrease in the rate of glycogenesis. After ACTH injection, glucose concentration in the liver was not significantly depleted but after 12 h or 24 h of food and water deprivation it was significantly depleted (P < 0.05). Plasma corticosterone concentration provided different insight into the effect of the stressor on hen physiology under acute and chronic conditions. Our data suggest that extending our evaluation of stress to the site of corticosterone action, that is, the target tissue, may enhance our ability to evaluate stress and the welfare of laying hens.