Non-cage Systems Research Articles

Spatiotemporal understanding of behaviors of laying hens using wearable inertial sensors

Automatic detection of behaviors and locations has been increasingly needed in the management of non-cage systems where hen behaviors are highly diverse and active. Here we show a technology to spatiotemporally understand behaviors using a wearable inertial sensor, containing a three-axis accelerometer and three-axis angular velocity sensor (i.e., gyroscope), and a marker. Using supervised machine learning, we first developed a tool that automatically classified and counted 11 behaviors, including comfort behaviors such as head scratching and tail-wagging with small movements as well as dust-bathing with dynamic movements. As expected, these behaviors were observed more frequently in floor pens than in conventional cages (all P < 0.01). We also spatially mapped the behaviors in floor pens and visualized the behavioral frequency in each resource by detecting the colored markers on the sensor. Furthermore, using the time-series information included in the sensor data, we analyzed the behavioral transition from one behavior to another. The behavioral transitions were more complex in floor pens, and the number was higher in body shaking, tail-wagging, resting, litter scratching, dust-bathing, preening, and moving in floor pens than in conventional cages (all P < 0.05). Our tools presented deeper insights into where and what hens behaved and also suggested that connectivity between behaviors, as well as observing the frequency of a behavior, can be an important indicator for welfare assessment in laying hens.

Situation on the market of eggs from non-cage production systems

The objective of the study is to determine the share of eggs from non-cage production systems compared to eggs from cage systems, in the year when the extended transitional period expires (December 2023) for Serbian producers to comply with the welfare legislation, mandating the transition from the conventional cage breeding system to permitted systems (enriched cage system and non-cage systems (floor, aviary, free breeding - free ranges, organic production). Also, the objective of the study is to determine the structure of consumers within the group valueing the breeding system, which declares that it prefers free range eggs and organic eggs. The examination of the Belgrade market supply of eggs, including supermarkets (11), green markets (5) and specialized stores (5), and consumer attitudes was conducted through a survey (247 respondents in the Belgrade region). According to the results of the survey, it can be concluded that the supply of eggs from non-cage systems is minor, compared to eggs from the cage system, which have a share of 100%, it is 81.82% for eggs from the floor system, 54.54% for eggs from free range and 9.10% for organic eggs. The supply of organic eggs on the market is insufficient and mainly associated with specialized stores. For about 30% of consumers, the egg production system is very important, whereby the majority of consumers (53.45%) would prefer the eggs from free ranges, and among them the largest share are women (76.03%), consumers with higher education (67.10%), employed (78.38%), aged 36-55 and with higher monthly incomes. Based on the research results, it can be concluded that the process of harmonizing egg production with welfare regulations has an impact on the egg market, i.e. resulting in changes in the sense of greater share of eggs from non-cage systems compared to similar research in the earlier period. At the same time, although there is a growing awareness among consumers about the importance of the production/rearing system, it is still insufficient compared to certain European countries. The development of non-cage systems, as more favourable from the point of view of welfare and consumer expectations, should be given greater attention in the coming period, by acting through regulatory measures, education of producers and consumers, research and support in terms of incentives, subsidies and loans to producers who switch to alternative systems of raising laying hens.

Animal welfare with Chinese characteristics: Chinese poultry producers' perceptions of, and attitudes towards, animal welfare.

China's poultry industry faces challenges in adopting and sustaining cage-free systems for poultry production. Effective interventions are crucial to support producers transitioning from cages to alternative systems or maintaining cage-free systems to improve animal welfare. However, little is known about how Chinese poultry producers perceive animal welfare in relation to cage-free systems and the importance of animal welfare in poultry production. Through a qualitative interview study with 30 Chinese farm owners, managers and senior managers from large-scale egg and broiler farms using cages and non-cage systems (collectively referred to as "producers"), this paper explores Chinese poultry producers' attitudes and perceptions regarding animal welfare and welfare in different poultry housing systems. Template analysis was used to analyse the data from semi-structured interviews, which generated themes related to the participants' awareness and understanding of the concept of animal welfare, the factors that impacted their choices of different housing systems, and the perceived priorities in poultry production. The responses revealed that the participating producers had a strong awareness and knowledge of animal welfare. However, the participants' understanding of the term is heterogeneous: generally, egg producers emphasised natural behaviours, whereas broiler producers prioritised health and productivity. Nevertheless, profitability, leadership, and organisational policies primarily influenced housing system choices rather than animal welfare values. Economic motives drove egg producers towards cage-free systems, prompted by consumers' and companies' demand for cage-free eggs committed to transitioning away from cages by 2025. In conclusion, tailored interventions for different poultry sectors within China are necessary. While animal welfare values matter, economic incentives seem more promising for steering the shift towards and maintaining cage-free poultry production.

Comparison of Antimicrobial Resistance among Commensal Escherichia coli Isolated from Retail Table Eggs Produced by Laying Hens from the Cage and Non-Cage Housing Systems in Western Australia.

Antimicrobial resistance (AMR) has become a global public health concern in recent decades. Although several investigations evaluated AMR in commensal and pathogenic bacteria from different foods of animal origin in Australia, there is a lack of studies that compared AMR in commensal E. coli isolated from retail table eggs obtained from different laying hen housing systems. This study aimed to determine AMR and differences in AMR patterns among E. coli isolates recovered from retail table eggs sourced from caged and non-caged housing systems in Western Australia. Commensal E. coli isolates were tested for susceptibility to 14 antimicrobials using a broth microdilution method. Clustering analyses and logistic regression models were applied to identify patterns and differences in AMR. Overall, there were moderate to high frequencies of resistance to the antimicrobials of lower importance used in Australian human medicine (tetracycline, ampicillin, trimethoprim, and sulfamethoxazole) in the isolates sourced from the eggs of two production systems. All E. coli isolates were susceptible to all critically important antimicrobials except the very low level of resistance to ciprofloxacin. E. coli isolates from eggs of non-caged systems had higher odds of resistance to tetracycline (OR = 5.76, p < 0.001) and ampicillin (OR = 3.42, p ≤ 0.01) compared to the isolates from eggs of caged systems. Moreover, the number of antimicrobials to which an E. coli isolate was resistant was significantly higher in table eggs from non-caged systems than isolates from caged systems' eggs. Considering the conservative approach in using antimicrobials in the Australian layer flocks, our findings highlight the potential role of the environment or human-related factors in the dissemination and emergence of AMR in commensal E. coli, particularly in retail table eggs of non-cage system origin. Further comprehensive epidemiological studies are required to better understand the role of different egg production systems in the emergence and dissemination of AMR in commensal E. coli.

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 &lt; 0.05), while the genotype had an effect on the condition of the neck, back, and tail plumage (p &lt; 0.05). In both the FR and O systems, the plumage status was similar and superior to that in B (p &lt; 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.

Environmental impacts of the Australian poultry industry. 2. Egg production

Context Eggs, a dietary staple, are a low environmental-impact animal protein, although no quantified analysis has been published for the Australian egg industry. Aims This study determined baseline greenhouse-gas (GHG) emissions, fossil energy use, freshwater consumption, water stress, and land-occupation impacts for the Australian egg for 2020 and identified hotspots. Methods To understand the environmental credentials of the industry, an attributional life-cycle assessment was conducted using primary data collected from all major Australian production regions. Impacts were reported per kilogram of table eggs and per kilogram of shell- and protein-corrected eggs for cage (C), cage-free (CF) and free-range (FR) production. Monte Carlo analysis was used to assess uncertainty, and results are presented using the means and standard deviations. Key results Statistically significant (P &lt; 0.05) differences among all systems were found for GHG and land occupation, and between cage and non-cage systems for fossil energy use. Impacts were 1.2 ± 0.04 kg carbon dioxide equivalent (CO2-e), 10.7 ± 0.2 MJ, 177.2 ± 19.0 L, 84.5 ± 9.6 L H2O-e and 16.0 ± 1.6 m3, and 7.6 ± 0.1 m2/kg C eggs, 1.4 ± 0.03 kg CO2-e, 12.0 ± 0.3 MJ, 190.6 ± 23.1 L, 88.9 ± 10.3 L H2O-e and 17.5 ± 1.9 m3, and 8.1 ± 0.1 m2/kg CF eggs and 1.5 ± 0.04 kg CO2-e, 12.2 ± 0.3 MJ, 204.6 ± 23.9 L, 100.8 ± 10.7 L H2O-e and 19.1 ± 1.8 m3 and 8.7 ± 0.1 m2/kg FR eggs. Land use and direct land use-change emissions associated with imported soymeal were significant, contributing a further 0.6 ± 0.1, 0.7 ± 0.1 and 0.7 ± 0.1 kg CO2-e/kg C, CF and FR eggs respectively. More efficient feed conversion ratios (FCRs) drove lower impacts in C production. Feed production was the major hotspot, followed by the layer farm and pullet rearing operations. Conclusions Reducing impacts will be most effective through changing diets to reduce reliance on high environmental-impact feed commodities, FCR improvements and energy efficiency measures to reduce housing energy demand. Improved land management is likely to have resulted in isolated small levels of carbon sequestration in Australian cropland over the analysis period, offsetting some GHG emissions. Further reduction in environmental impacts will rely on decarbonisation of feed supply chains and prioritisation of low environmental-impact feed commodities. Implications Being the first industry-wide environmental assessment of Australian egg production, this study has highlighted the need for ongoing assessment to isolate inter-annual variability, determine long-term trends, and investigate pathways to reduce impacts into the future.

The Impacts of Colony Cages on the Welfare of Chickens Farmed for Meat.

There is growing interest in keeping meat chickens in modern colony cages (CCs) rather than conventional litter-floor barns. Suggested welfare improvements for chickens in such systems include reduced bodily lesions due to lower contact with flooring contaminated with faeces and urine, due to slatted flooring and automated faeces removal. This systematic review sought to determine the animal welfare impacts of CCs using slatted flooring, in comparison to litter-based non-cage systems. Overall, 23 relevant studies were retrieved. From one perspective, the extant research appeared mixed. Fifteen (65%) of these 23 studies identified some form of welfare concern about slatted floors, and thus CCs. Yet, when considering actual welfare indicators assessed, the tallies generated in favour of each housing system were similar. Crucially however, there were incomplete behavioural welfare measures in 100% of the empirical studies reviewed. Accordingly, significant welfare concerns exist about CCs, centring around behavioural deprivation. Given that over 70 billion chickens are farmed then slaughtered each year globally, widespread implementation of CCs would create a major animal welfare concern. Instead of implementing such CC systems, research and development is recommended into improving welfare outcomes of conventional litter barns using different forms of commercially feasible enrichment. As a minimum, a full behavioural analysis, as detailed in the Welfare Quality Assessment protocols, should form a mandatory part of any future studies aimed at assessing the welfare impacts of housing systems on farmed chickens.

Research Note: Effect of light intensity of calcium homeostasis in pullets

The impact of varying light intensities on layer pullets is not yet well understood. Behaviorally, brighter illumination may increase pullet activity levels by allowing better navigation in the complexity of non-cage systems. In addition, light intensity was previously demonstrated to affect the levels of calcium and phosphate regulating hormones in mice. The objective of this study was to examine how exposure of pullets to different light intensity affects their calcium and phosphorus homeostasis. Lohmann LSL-Lite and Lohmann Brown-Lite pullets were randomized into 4 individually controlled rooms with 6 pens per room, which were assigned to 10 or 50 lux light intensity supplied via white LED lighting during the photophase. After 8 and 16 wk of exposure, plasma calcium, phosphorus, and magnesium were measured by inductively coupled plasma optical emission spectrometry; and parathyroid hormone, 1,25-dihydroxyvitamin D, fibroblast growth factor 23, and markers of bone formation and resorption were measured by ELISA. Intestine and kidney samples were collected at 16 wk and gene expression of receptors for calcium and phosphate regulating hormones was assessed. The data were analyzed by one-way ANOVA. Lohmann Brown-Lite pullets exposed to 50 lux for 8 wk exhibited lower ionized Ca levels and a trend for increased bone formation markers compared to pullets reared in 10 lux. Thus, higher light intensity during rearing may beneficially affect calcium homeostasis and bone formation in young Lohmann Brown-Lite chicken.

The Relationships between Damaging Behaviours and Health in Laying Hens.

Simple SummaryThe design of housing systems and genetic selection of laying hens have in the past focused mainly on productivity, excluding issues around the animals’ behavioural needs and welfare. Because of inadequate housing conditions and especially a barren environment, behavioural disorders such as feather and body pecking, as well as cannibalism, occur in the modern layer industry. Since conventional cages for egg production were banned in the European Union in January 2012, alternative systems such as floor, aviary, free-range, and organic systems have become increasingly common and now concern over 50% of hens housed in Europe. Despite the many advantages that come with non-cage systems, the shift to a housing system where laying hens are kept in larger groups and more complex environments has given rise to new challenges related to management, health, and welfare. We have carried out a review showing the close relationships between damaging behaviours and health in modern husbandry systems for laying hens.Since the ban in January 2012 of conventional cages for egg production in the European Union (Council Directive 1999/74/EC), alternative systems such as floor, aviary, free-range, and organic systems have become increasingly common, reaching 50% of housing for hens in 2019. Despite the many advantages associated with non-cage systems, the shift to a housing system where laying hens are kept in larger groups and more complex environments has given rise to new challenges related to management, health, and welfare. This review examines the close relationships between damaging behaviours and health in modern husbandry systems for laying hens. These new housing conditions increase social interactions between animals. In cases of suboptimal rearing and/or housing and management conditions, damaging behaviour or infectious diseases are likely to spread to the whole flock. Additionally, health issues, and therefore stimulation of the immune system, may lead to the development of damaging behaviours, which in turn may result in impaired body conditions, leading to health and welfare issues. This raises the need to monitor both behaviour and health of laying hens in order to intervene as quickly as possible to preserve both the welfare and health of the animals.

Evaluating the sustainability of egg production in Turkey: A standardized data approach

This study aimed to evaluate egg production systems within the scope of sustainability criteria under Turkey conditions. A standardized data approach was used to measure sustainability and compare egg production systems. The study covered a one-year egg-laying cycle of 24 farms including conventional cage, organic, and free-range systems. Hens in conventional cages had higher egg production and lower feed intake compared to hens in organic and free-range systems. The highest mortality was found in the free-range hens while the lowest was in the conventional cage system. All hens were fully feathered in the organic egg production system, which was followed, by free-range and conventional cage. This result led to a better social sustainability score for non-cage systems. Economic issues of sustainability had higher scores in conventional cage and organic egg production than those in the free-range system. The hen number per m2 in the total farm area was lower in organic and free-range than those in conventional cage systems (P=0.003), nonetheless, the total land occupation area was found similar. The standardized data used in this study shows that management practices should be improved in free-range and organic egg production systems to achieve higher sustainability scores in Turkey.

Effects of Rearing Aviary Style and Genetic Strain on the Locomotion and Musculoskeletal Characteristics of Layer Pullets.

Simple SummaryConsumer trends have led to the popularisation of eggs from hens housed in non-cage systems. Aviaries are common non-cage systems that consist of multi-tiered structures with essential resources located within. Being a ground-dwelling species, laying hens must learn when they are young to navigate aviaries, and develop the strength to do so. However, there are different styles of aviaries with varying degrees of structural complexity in which young laying hens (pullets) are reared. This study examined the differences in locomotion and musculoskeletal characteristics of white- and brown-feathered strains of pullets housed in three different styles of rearing aviaries (low, moderate, and high structural complexity) on commercial farms. Pullets in the most complex system spent the most time locomoting, and white-feathered strains in the highly complex systems performed the most jumps and flights. While there were no differences in muscle weights between aviary styles, white-feathered strains, and pullets in the most complex aviary had stronger leg bones than brown-feathered strains and pullets in the least complex system. These results indicate that the style of the aviary in which pullets are reared can affect their bone strength, most likely through differences in the load-bearing exercises performed.Previous research indicates that the musculoskeletal development of pullets is improved when pullets are reared in aviaries compared to conventional rearing cages. However, there are considerable differences in rearing aviary design. To measure locomotion and musculoskeletal development of brown (n = 7) and white-feathered (n = 8) strains of pullets, 15 commercial flocks in three styles of rearing aviaries differing in structural complexity (n = 5 per style) were visited three times: 25.9 ± 6.67, 68.0 ± 4.78, and 112.1 ± 3.34 days of age. Locomotion (duration of standing, sitting, walking, running, flying, and rates jumping, flying, group running and walking) was analysed from videos recorded three times per day: at the beginning, middle, and end of the light cycle. Pullets for dissection were taken on visits 2 and 3. Pullets in the most complex system (style 3; S3) spent the most time locomoting throughout rearing (p < 0.05). Pullets in S3, particularly white-feathered strains, performed the highest rate of vertical transitions (p < 0.05). There were no differences in any of the proportional muscle weights between aviaries styles (p > 0.05) despite the differences in locomotion. White-feathered strains, however, had proportionally heavier pectoralis major (p < 0.0001), pectoralis minor (p < 0.0001), and lighter leg muscles (p < 0.0001) than brown-feathered strains. White-feathered strains and pullets in S3 also had proportionally stronger tibiae and femurs than brown-feathered strains and pullets housed in the least structurally complex system (style 1; S1) (p < 0.05). However, there were no differences found in the breaking strength of the radius and humerus between strain colours or aviary styles (p < 0.05). Therefore, strain, as well as differences in rearing aviary design, can affect the types of locomotion that growing pullets perform, which may, in turn, impact their skeletal development.

Cage production and laying hen welfare

Although many factors affect the welfare of hens housed in cage and non-cage systems, welfare issues in cage systems often involve behavioural restrictions, whereas many welfare issues in non-cage systems involve health and hygiene. This review considers and compares the welfare of laying hens in cages, both conventional and furnished cages, with that of hens in non-cage systems, so as to highlight the welfare implications, both positive and negative, of cage housing. Comparisons of housing systems, particularly in commercial settings, are complex because of potentially confounding differences in physical, climatic and social environments, genetics, nutrition and management. Furthermore, some of the confounding factors are inherent to some specific housing systems. Nevertheless, research in commercial and experimental settings has indicated that hens in conventional and furnished cages have lower (or similar), but not higher, levels of stress on the basis of glucocorticoid concentrations than do hens in non-cage systems. Furthermore, caged hens, generally, have lower mortality rates than do hens in non-cage systems. However, the behavioural repertoire of laying hens housed in conventional cages is clearly more compromised than that of hens in non-cage systems. In contrast to conventional cages, furnished cages may provide opportunities for positive emotional experiences arising from perching, dust-bathing, foraging and nesting in a nest box. Some have suggested that the problems with modern animal production is not that the animals are unable to perform certain behavioural opportunities, but that they are unable to fill the extra time available with limited behaviours when they have no need to find food, water or shelter. Environmental enrichment in which objects or situations are presented that act successfully, and with a foreseeable rewarding outcome for hens by also providing regular positive emotional experience, is likely to enhance hen welfare. Research on cage systems highlights the importance of the design of the housing system rather than just the housing system per se.

The impact of management, husbandry and stockperson decisions on the welfare of laying hens in Australia

The present review examines the impact of management and husbandry decisions on the welfare of laying hens in Australia. The literature on many of these aspects is lacking for the Australian egg industry, and, indeed, for the egg industry in general. Management decisions that can affect hen welfare relate to the initial farm design, husbandry routines, and staff selection and training. As modern laying houses represent a considerable financial investment, the decisions made during the design phase are likely to affect both the hens and stockpeople for substantial periods. Hens in cage systems may benefit from fewer tiers and greater space allowances. In non-cage systems, the brown genotypes used in the Australian egg industry may benefit from lower structures that accommodate their heavier and less agile bodies. Keel fractures can be reduced by improving the skeletal health and spatial cognition of laying hens during the rearing period, in addition to minimising the distances they need to jump when navigating aviary structures. The addition of a wintergarden to fixed free-range systems appears to be beneficial. Housing hens in mobile units on free-range farms may challenge their welfare, particularly in relation to heat stress. There is also room for improvement in biosecurity practices and health monitoring of hens, as these appear to be lacking at some farms. The current strains of hen used in free-range systems may not be best suited to these conditions, on the basis of their body condition and flock uniformity. Feed quality may also need to be monitored for quality assurance and optimal hen nutrition. Hen welfare during depopulation can be improved through staff training and by reducing staff fatigue. Euthanising spent hens on farm offers welfare benefits over transporting spent hens to an abattoir. Both hen welfare and working conditions for stock people should be considered when designing laying houses to provide suitable conditions for both hens and stockpeople. This will help improve the job satisfaction of stockpeople, which may translate into better care for the hens and may aid in retaining quality staff. Stockpeople must be recognised as vital contributors to hen welfare in the egg industry, and it is important for the egg industry to continue to attract, train and retain skilled stockpeople to ensure that they enjoy their job and are motivated to apply best-practice care for their flocks. Promoting the animal-care aspect of stockmanship in combination with a supportive managerial environment with optimal working conditions may increase the attractiveness of the egg industry as a place to work.

Effects of Management Strategies on Non-Beak-Trimmed Laying Hens in Furnished Cages that Were Reared in a Non-Cage System.

Simple SummaryThe practice of beak trimming in laying hens limits the negative consequences of injurious pecking, but could be prohibited by future regulations. We addressed in this study the question of how to prevent or minimize injurious pecking and its consequences, especially when beak trimming is not carried out. We found that a combination of different management strategies applied from rearing to laying stages improved to some extent the welfare of non-beak trimmed birds (lower mortality and fear of a novel object, better feather cover up to 61 weeks of age). Fiber supplementation in the feed did not provide any benefit on pecking-related problems. We suggest practical solutions to limit the consequences of injurious pecking where non-beak-trimmed animals are reared in barn system and transferred to furnished cages, while preserving good welfare, health and productivity.Beak trimming in laying hens limits the negative consequences of injurious pecking, but could be prohibited by future regulations. This study assessed a combination of management strategies during the rearing period (objects, perches, music, human presence) and laying period (scratching mats, objects, feed fiber supplementation) to raise non-beak-trimmed animals. The welfare and laying performances of beak-trimmed (T) and non-beak-trimmed (NT) ISA Brown birds were compared between groups with (E) or without (NE) these strategies, with or without fiber supplementation in the diet during laying period. Fiber supplementation did not provide any benefit on pecking-related problems. In comparison with NT-NE birds, NT-E birds had lower mortality, were less fearful of a novel object, and had a better feather cover, without a negative impact on productivity (same laying rate and egg quality). Although this study showed advantages of beak trimming (T birds had higher body weights, laying rates and lower hen mortality than NT birds), it highlighted related problems (increasing pullet mortality, decreasing early weights and increasing beak defects). This study proposes practical solutions to limit the consequences of injurious pecking in non-beak-trimmed animals.

Laying hen’s mobility is impaired by keel bone fractures and does not improve with paracetamol treatment

Keel bone fractures (KBF) in laying hens pose a severe problem for animal welfare as they are likely to be associated with pain and suffering. Furthermore, they are suspected to hinder or restrict hens in their performance of natural species-specific behaviour. The aim of this study was to determine whether KBF affect laying hen behaviour in a non-cage system and whether this alteration is caused by pain. Forty Brown Nick and 40 Nick Chick hens were individually marked, and video recorded in eight experimental pens containing two perches with a platform attached to a ramp to facilitate access, an elevated nest box with platform for landing, drinker, feeder and litter. Data was collected at 37 and 39 weeks of age (WoA) on two consecutive days each at three time points per day. Paracetamol was administrated via drinking water either during the 37th or the 39th WoA. Additionally, activity assessments were done at 26, 28, and 30 WoA to detect differences pre-fracture. To assess the keel bone (KB) state, hens were radiographed at 30, 37 and 39 WoA and KB categorised as having no fracture, healed fracture(s) or fractures with a visible fracture gap. The odds of perch or nest access (i.e., vertical locomotion) decreased when a fracture gap was visible (p = 0.004) but the walking pace on ramps leading to the perches was not affected by KBF. Paracetamol did neither reverse the decrease in mobility behaviour nor did it affect the walking pace on the ramp. Of the hens with fractures featuring a visible fracture gap, those receiving paracetamol performed less rapid comfort behaviours (e.g., wing flapping) than hens receiving vehicle (i.e. water) only (p = 0.04). Preening and dustbathing duration was increased with the administration of paracetamol (p = 0.02) though was unaffected by KBF in this study. No difference was found in activity before the fracture(s) occurred. In conclusion, we show that KBF affect laying hen mobility behaviour in non-cage systems and thus a reduction of KBF would improve laying hen welfare.

Free-range laying hens: using technology to show the dynamics and impact of hen movement

Free-range laying hens are provided with the opportunity to access various structural areas, including open floor space, feed areas, water lines, next boxes, perches, aviary tiers, winter gardens and ranges. Different individual location preferences can lead to the development of hen subpopulations that are characterised by various health, welfare and performance parameters. Understanding the complexity of hen movement and hen interactions within their environment provides an opportunity to limit the disadvantages that are associated with housing in loose husbandry systems and aids in decision-making. Monitoring hen movement using modern technologies such as radio-frequency identification (RFID), optical flow patterns, image analysis and three-dimensional (3D) cameras allows the accumulation of big data for data mining, clustering and machine learning. Integrating individual-based management systems into modern flock management will not only help improve the care of under-performing hens, but also ensure that elite hens are able to use their full genetic potential, allowing an ethical, sustainable and welfare friendly egg production. This review highlights the dynamics and impact of hen movement in free-range systems, reviews existing knowledge relevant for feeding hens in non-cage systems, and outlines recent technological advances and strategies to improve the management of free-range laying hens.

A Description of Laying Hen Husbandry and Management Practices in Canada.

Simple SummaryFurnished cage and non-cage (single-tier or multi-tier) housing systems are increasingly used worldwide in efforts to improve laying hen welfare. Canadian laying hen farms are undergoing a similar transition, however, little is known about the housing and management of laying hens in these housing systems in Canada. Data collected through farmer questionnaires from 65 laying hen flocks across Canada revealed commonly used management practices in furnished cage (26), single-tier (17) and multi-tier systems (22). Non-cage systems should allow hens to perform natural behavior (e.g., foraging/dustbathing). However, a proportion of non-cage systems either did not provide litter or considered manure as a litter substrate, which could have implications for consumer perspectives on these systems. Daily flock inspections and vaccination schemes were the main practices used to maintain flock health, whereas veterinarian involvement on-farm and in the development and implementation of a flock health plan was less common. Further research is needed to make clear recommendations and to investigate how to facilitate management changes by farmers currently transitioning to furnished cage and non-cage housing systems.Canadian laying hen farms are transitioning from conventional cage housing to furnished cage and non-cage housing systems to improve laying hen welfare. However, little is known about the current housing and management systems in Canada. This study addresses this knowledge gap by describing different housing and management practices used on farms where laying hens were housed in furnished cages or non-cage housing systems. A questionnaire covering farm and housing conditions, litter management, nutrition and feeding, environmental control, flock characteristics, rearing and placement, health, egg production and performance were distributed through provincial egg boards to 122 producers across Canada. Data were collected from 65 laying hen flocks (52.5% response rate) in 26 furnished cage, 17 single-tier and 22 multi-tier systems. Flocks were on average 45.1 ± 14.59 weeks old (range: 19–69 weeks). Frequencies of different management practices were calculated according to housing system. Most flocks were reared in the same housing system as they were housed in during lay, with the exception of furnished cage layers which were reared in conventional cage systems. Results indicated that a large proportion of non-cage systems were either fully slatted or had manure as a litter substrate, which could have implications for consumer perspectives on these systems. Further research is needed to develop clear recommendations on proper litter management for farmers. In general, flock health was managed through daily inspections and vaccination schemes, whereas veterinarian involvement on-farm was less common. Vaccination, hygiene, and effective biosecurity should be maintained to ensure good health in laying hens in furnished cage and non-cage systems during the transition to these systems.

Improving utilization of nests and decreasing mislaid eggs with narrow width of group nests

Provision of nest boxes is necessary for laying hens, especially in non-cage systems. This study investigated the effects of nest width on nest utilization and mislaid eggs. Hy-Line Browns hens were transferred from conventional cages to perchery pens at 12 weeks of age. Two experiments were conducted to mutually verify the hypothesis that narrowing group nests would improve nest utilization and reduce mislaid eggs. In experiment 1, group nests of 150 cm wide in two pens were partitioned at intervals of 50 cm and 37 cm, respectively. In experiment 2, partition panels were removed after acclimation. The number of mislaid eggs and nest eggs in each pre-set section were compared. Results indicated that narrowing group nests had positive effects on improving usage uniformity and efficiency of group nests. Nest eggs were more evenly distributed on the egg belt in both narrowed group nests, which was indicated by the significant decrease of variance among different sections. The proportion of mislaid eggs decreased by 3.5% in 37 cm treatment and 4.7% in 50 cm treatment, respectively. As expected, reuse of the 150 cm group nests after removal of partition panels lowered the usage uniformity of group nests. A growth of three percentage points was found for the proportion of mislaid eggs after removing the partition panels in 50 cm treatment. The present results indicated that it is the width of the nest box that works for a better use of group nests. In conclusion, adding partition panels at intervals of 50 cm and 37 cm in group nests both are effective on nest usage and decreasing the occurrence of mislaid eggs. Keywords: group nest, nest width, utilization, mislaid eggs, hen house, non-cage system, bird welfare DOI: 10.25165/j.ijabe.20181101.3167 Citation: Zheng H Y, Li B M, Chen G, Wang C Y. Improving utilization of nests and decreasing mislaid eggs with narrow width of group nests. Int J Agric & Biol Eng, 2018; 11(1): 83–87.

The motivation of hens to lay eggs on the floor in non-cage systems has a heritable background

Summary Large scale egg production in cages has been practiced worldwide for many years. However, recently consumer preferences have been shifting towards eggs produced in non-cage environments. In the March 2015 issue of Poultry Science a series of papers were presented from a comparative study of three production systems: conventional cages, enriched cages and aviary systems. Among the many issues reported we paid attention to floor eggs that is of no interest in cages but plays a role in enriched cages and in particular in aviary systems. The researchers called on attention to the cost of collecting floor eggs in the aviary systems and to the fact that floor eggs were more contaminated. In the Scandinavian Selection and Crossbreeding Experiment (SSCE) in 1980, birds were kept both in cages as well as in aviary systems for 5 generations. In this presentation we demonstrate that the frequency of floor eggs over 5 generations was reduced to 55% compared to the control line, and this was statistical significant. Although not being able to estimate the heritability it can be stated that some degree of heritability exists. In the meantime an electronically controlled nest has been developed. This would make it much easier for breeders to monitor individual egg laying behaviour of laying hens kept in aviary/floor management without the laborious work when using trap nests. By doing this, a more exact estimation of the genetic basis of laying floor eggs would be possible.

Ramps and hybrid effects on keel bone and foot pad disorders in modified aviaries for laying hens

Non-cage systems provide laying hens with considerable space allowance, perches and access to litter, thereby offering opportunities for natural species-specific behaviors. Conversely, these typical characteristics of non-cage systems also increase the risk of keel bone and foot pad disorders. The aim of this study was twofold: 1) to investigate if providing ramps between perches (housing factor) reduces keel bone and foot pad disorders and 2) to test for genetic predisposition by comparing 2 different layer hybrids. In a 2 × 2 design, 16 pens were equipped either with or without ramps between perches and nest boxes (8 pens/treatment), and housed with either 25 ISA Brown or Dekalb White birds per pen (in total 200 birds/hybrid). Keel bone injuries and foot health were repeatedly measured via palpation and visual assessment between 17 and 52 wk of age and daily egg production was recorded. The relationships between the dependent response variables (keel bone and footpad disorders, egg production) and independent factors (age, ramps, hybrid) were analyzed using generalized linear mixed models and corrected for repeated measures. Ramps reduced keel bone fractures (F1,950 = 45.80, P < 0.001), foot pad hyperkeratosis (F1,889 = 10.40, P = 0.001), foot pad dermatitis (F1,792 = 20.48, P < 0.001) and bumble foot (F1,395 = 8.52, P < 0.001) compared to pens without ramps. ISA Brown birds sustained more keel bone fractures (F1,950 = 33.26, P < 0.001), had more foot pad hyperkeratosis (F1,889 = 44.69, P < 0.001) and laid more floor eggs (F1,1883 = 438.80, P < 0.001), but had fewer keel bone deviations (F1,1473 = 6.73, P < 0.001), fewer cases of foot pad dermatitis (F1,792 = 19.84, P < 0.001) and no bumble foot as compared to Dekalb White birds. Age, housing and hybrid showed several interaction effects. Providing ramps proved to be very effective in both reducing keel bone and foot pad problems in non-cage systems. Keel bone and foot pad disorders are related to genetic predisposition. These results indicate that adaptation of the housing systems and hybrid selection may be effective measures in improving laying hen welfare.