Integrating animals into a farm supports a closed or semi-closed production system where nutrients are recycled and off-farm inputs are reduced. In comparison to other livestock, chickens can be a low-investment option for animal-crop integration of small-scale, diversified, vegetable farms. Although crop-animal integration poses many potential benefits to farms, soils, and the environment, there are significant food safety risks when considering the production of vegetables in close proximity to raw manure. The objectives of this study were to examine the effects of poultry integration with meat chickens (broilers) in two different seasons on soil health, food safety, vegetable yield, and poultry feed efficiency in organic vegetable cropping systems. We explored these effects in an open field study with three rotation treatments (two that integrated chickens and a no-chicken control): vegetables-cover crop (V-CC; control treatment), vegetables-cover crop-poultry (V-CC-P), and vegetables-poultry-cover crop (V-P-CC). In response to crop rotation, over three years, we monitored soil nutrient status, soil microbial biomass carbon (MBC), permanganate oxidizable carbon (POXC), and microbial catabolic potential and diversity using Biolog® microplates. The presence or absence of foodborne pathogens in soil and vegetables was also measured. Nitrate–nitrogen (NO3–N) was higher in V-P-CC in year 2 as compared to both V-CC and V-CC-P (P = 0.001 and <0.001, respectively). After poultry removal in the summer of year 2 and year 3 V-P-CC was on average two times higher in NO3–N as compared to V-CC and V-CC-P, respectively. After chicken removal in the autumn of year 3 V-CC-P was 2.1 and 1.8 times higher in NO3–N as compared to V-CC and V-P-CC, respectively. On average phosphorus (P) increased by 45% in year 2 and by 13.2% in year 3. Microbial biomass carbon (MBC) increased from after harvest (summer) in year 1 to the end of the season (autumn) of year 2 from 219.75 to 303.23 mg carbon (C) kg−1. Integrating poultry increased MBC by 25%, on average between both treatments across all sampling dates, compared to the V-CC (P = 0.042). The vegetable-cover crop control (V-CC) preferentially used carbohydrates, compared to V-P-CC which corresponded to greater amino acid usage. Escherichia coli O157:H7 was detected in all plots in the spring of year 3 and select replications of plots in the autumn of year 3. Salmonella spp. was found in one plot in year 2. No pathogens were detected on the spinach crop when leaf surfaces were tested. Integrating chickens into organic vegetable crop rotations increases NO3–N and has the potential for off-farm fertilizer reductions if time and stocking density are further examined. However, poultry feed is often an off-farm input and should be considered when determining the true N input of this system. Soil health may be improved, but MBC and other soil health indicators should be monitored with longer-term rotations. There are food safety risks that come with the integration of chickens into vegetable production and fields should be treated as if raw manure has been applied. Despite the potential benefits of integrating poultry into vegetable crop rotations, more research on these systems is required to determine optimum integration strategies that provide maximum benefit to the producer, the animals, and the environment.

There is a trend towards the adoption of cage-free housing systems in the egg industry across Asia. While cage-free housing systems can hold significant animal welfare advantages over cages, there can also be challenges in managing these systems. This exploratory study aimed to investigate the perspectives of egg producers on the main challenges and proposed solutions associated with cage-free systems in China, Indonesia, Thailand, Japan, Malaysia, and the Philippines. Cage-free producers found disease prevention and maintaining a healthy profit margin more difficult than producers from cage farms, while it was less difficult to provide environmental enrichment in cage-free systems compared to cage farms. The top challenges for cage-free producers were the cost of production, system management, disease, sales, and egg production, and the top proposed solution was to improve on-farm practices and efficiencies. Eighty-one percent of egg producers believed that more support is needed to maintain their farms than is currently available, and support was most needed in helping to improve sales, improve farm operations, lower farm costs, and provide information for producers in the form of education and training. Most responses identified the government as the stakeholder that should offer support. These results may help direct further studies in this field as well as supplying information to develop relevant initiatives with an emphasis on education and training, thereby improving animal welfare on cage-free farms and increasing the uptake of high welfare cage-free farms across the region.

This study compares various morphometric features of two strains of broilers, selected and ‘relaxed’ (ie random-bred), raised under two feeding regimes, ad-libitum-fed and restricted-fed. We consider the possible consequences of the different body shapes on the musculoskeletal system. The ad-libitum-fed selected birds reached heavier bodyweights at younger ages, had wider girths, and developed large amounts of breast muscle which probably displaced their centre of gravity cranially. At cull weight, they had shorter legs than birds in the other groups and greater thigh-muscle masses; therefore, greater forces would have to be exerted by shorter lever arms in order to move the body. The tarsometatarsi were broader, providing increased resistance to greater loads, but the bones had a lower calcium and phosphorus content, which would theoretically make them weaker. Many of these morphological changes are likely to have detrimental effects on the musculoskeletal system and therefore compromise the walking ability and welfare of the birds.

Developmental instability, of which fluctuating asymmetry is the most commonly used and recommended measure, has recently been claimed to be an objective, integrated and retrospective indicator of animal welfare. The theoretical and empirical grounds for these claims are reviewed. In theory, carefully selected composite indices of fluctuating asymmetry are valid indicators of animal welfare in the sense that they reflect the ability of the developmental processes of an animal, with a given genetic constitution, to cope with environmental stressors. Relevant scientific experiments are scant and are mainly restricted to poultry, but they are on the increase and they largely support the application of developmental instability for assessing animal welfare. A scheme for monitoring farm animal welfare based purely on measures of developmental instability would have important advantages, but cannot be recommended yet. It cannot be ruled out that certain factors are clearly relevant to the welfare status of an animal but do not notably/proportionally affect its morphogenesis. Moreover, such a monitoring scheme would not be appropriate for applications with an emphasis on problem analysis/management.

Shackling of commercial poultry involves the insertion of each leg into parallel metal slots and holding the bird inverted for a period of time before stunning and slaughter. Nociceptors signalling noxious stimulation of the skin have been identified in the beak and feathered skin but not in the scaly skin of the leg. The physiological properties of the C-fibre mechanothermal (CMT) nociceptors in the skin over the tarsometatarsus in the lower leg were studied in response to quantitative mechanical stimulation. The electrical activity was recorded from single C-fibres dissected from the parafibular nerve in anaesthetized animals. The receptive fields of these receptors were small and spot-like, measuring in the region of 1-3 mm in diameter. The threshold to mechanical stimuli ranged from 0.8-15 g using von Frey filaments, and from 3-33 g using a 0.5mm probe mounted on a feedback-controlled stimulator. Stimulus response curves using a ramp-and-hold stimulus were recorded for a number of fibres. After comparing these threshold measurements and the stimulus response data with previous measurements of the force applied to the legs during shackling, it was concluded that shackling is likely to be a very painful procedure.

This study tests the hypothesis that growth rate and bodyweight affect walking ability in broilers by comparing objective measurements of the spatial and temporal gait parameters of several groups of birds. Two strains of birds were used (relaxed and selected), raised on two feeding regimes (ad-libitum and restricted), and culled at the same final bodyweight (commercial cull weight of 2.4 kg). The ad-libitum-fed selected birds walked more slowly, with lower cadences, and took shorter steps. The steps were wider, and the toes were pointed outwards, resulting in a wider walking base. They kept their feet in contact with the ground for longer periods, having longer percentage stance times, shorter percentage swing times and increased double-contact times compared to the relaxed birds. These changes serve to increase stability during walking and are a likely consequence of the morphological changes in the selected broiler — in particular, the rapid growth of breast muscle moving the centre of gravity forward, and the relatively short legs compared to their bodyweight (see Corr et al, pp 145-157, this issue). This altered gait would be very inefficient and would rapidly tire the birds, and could help to explain the low level of activity seen in the modern broiler.

This pilot experiment was conducted to ascertain whether CO2-enriched high expansion foam could be an acceptable and efficient alternative in emergency killing of poultry. This method could have wide-ranging applications but with particular emphasis on small (backyard) flocks, free-range sheds or open (naturally-ventilated) housings. The objectives of the study were as follows: 1) to determine whether the injection of foam and being covered with foam leads to fear or panic reactions in birds; 2) to determine the time taken to render birds unconscious and dead and 3) to determine whether any pathological abnormalities are observed post mortem. Six laying hens were individually exposed to increasing levels of CO2 foam with an expansion rate of 300:1. The test box containing individual birds filled with foam within 30 s. During foaming, two out of six birds tried to escape from the test box (1–2 attempts per bird). Apart from displaying greater alertness, birds showed no aversive reactions to the CO2 foam. Twenty-to-thirty seconds after being covered with foam, five of the six birds demonstrated one or two forcable or convulsive movements. Movement patterns and muscle jerks immediately following this convulsive movement led us to believe that birds lost consciousness at this moment and, within approximately three minutes, all birds had ceased to have a heartbeat. Macroscopic post mortem examination of the birds revealed no abnormalities and microscopic examination showed moderate bronchiolar bleeding and a small amount of alveolar bleeding. After assessing behavioural parameters, measurements of heart rate and pathological data, it is our conclusion that CO2 foam has the potential to be an acceptable method of killing poultry. It is advisable for this method to be examined on a larger scale in order to assess the implications of physiological (EEG and ECG) measurements on welfare.

Groups of end-of-lay (spent) hens were subjected to three different treatments on a short flat-belt conveyor. Observations of bird behaviour indicated that the incidences of wing flapping, loss of balance and alarm calling significantly increased when birds were conveyed up and down slopes in comparison to being conveyed horizontally (P<0.01). Birds were significantly more hesitant when approaching the incline compared to the horizontal (P<0.001). However, differences in behavioural responses were not reflected in times spent in tonic immobility or open-field tests. There were no significant differences for the three treatments. It is possible that human contact, before and after conveying, was a more significant fear stimulus than the treatment itself.

Assessment of mass-produced animal-housing equipment can serve as a basis for improving animal welfare. A number of European countries have adopted various legal approaches to such assessment. In Germany, welfare assessment of housing equipment is voluntary, but minimum standards can be set by regulation for the assessment procedure and for the qualifications of the persons involved. From a scientific perspective, the time and resource constraints pose some problems, particularly as they apply to a voluntary procedure. For reasons of practicability, certain compromises will be required. Nevertheless, it is important to ensure that each assessment procedure is based upon scientific principles and considers animal welfare aspects to a sufficient extent. A proposal for the minimum standards of an assessment procedure has been elaborated by the Animal Welfare Committee of the German Agricultural Society (Deutsche Landwirtschafts-Gesellschaft, DLG), a shortened version of which is presented here. The animal welfare impact of such a regulated but voluntary procedure will be less than that of an obligatory assessment; however, the relatively flexible approach may still significantly contribute to the improvement of welfare aspects of livestock housing.

Bodily contact with water is a novel and aversive experience for broiler chickens, and this has been used when designing the Latency to Lie (LTL) test. The original testing procedure, in which the birds are tested in groups, involves a certain settling period, which makes the test time-consuming to carry out on commercial broiler farms. Our modifications of the LTL test for on-farm use mean that a) the birds are tested individually without visual contact with other birds; and b) the water tub is already filled with water when the birds are placed in it. The results from the LTL tests can then be compared with the scores achieved for each individual bird on the commonly used ‘gait scoring’ procedure. At 14 farms participating in a larger survey, we used three birds of each gait score from 0 to 4 (when available) for LTL testing. The time spent standing before making the first attempt to lie down was recorded. The results show a clear negative correlation (r = -0.86, P < 0.001) between time spent standing and gait score. The mean LTL values for the different gait scores were all significantly (P < 0.01) different. There was no significant difference in LTL results between flocks. The method described appears to be well suited for on-farm use. If further developed, it could become a useful tool in monitoring programmes for the ongoing efforts aiming at decreasing the levels of leg weakness in modern broiler production.

Traditional battery cages for laying hens will soon be banned in the EU but the increased risk of feather pecking (FP) hampers the adoption of alternative housing systems. FP can cause injury and lead to cannibalism and the painful death of target birds. Current management practices (beak trimming, low light) have associated problems. In a joint European project we sought alternative solutions. In our study of associated traits, birds from a line showing low (LFP) rather than high feather pecking (HFP) exhibited greater sociality (motivation to be near companions) and a passive ‘coping’ style. High sociality and passivity were also negatively associated with FP in adults. These findings may guide future breeding programs. Trimming hens’ feathers to mimic the results of FP elicited pecking and some cannibalism, even by birds that had previously shown no FP. Social transmission of gentle but not severe FP occurred when LFP and HFP birds were housed together. Gentle pecking could conceivably lead to severe FP. We then examined chickens’ pecking preferences to guide environmental enrichment strategies. Bunches of string elicited substantially greater interest than other stimuli, including feathers, and white or yellow string was the most attractive. The birds’ manipulation of the string resembled preening. Incorporating silver beads or moving the devices reduced pecking. String sustained lengthy interest, reduced FP in HFP birds, and decreased feather damage in caged layers on a commercial farm. String offers effective, affordable and practicable environmental enrichment. The integrated application of appropriate environmental and genetic strategies is likely to attenuate the expression of FP and its harmful consequences.

The welfare of farm animals is strongly influenced by the man-made environment. Welfare problems also arise from reduced homeostatic capacities in animals. Feed additives, used to promote growth or to prevent diseases can alter the animals' self-regulating capacities thus affecting their welfare. The EU regulates the use of these additives within specified groups of Directive 70/524/EEC. Although these feed additives can be regarded as prescription-free veterinary drugs, critical remarks on their desired and adverse effects have received little attention.

A survey of the available literature shows that about one-third of licensed feed additives alter adrenal function in vitro. Reports of the adverse effects of anticoccidial additives in vivo suggest they can be classified under three headings: (i) substances with a very narrow safety margin (the difference between the permitted dose and the dose with adverse effects) and often irreversible effects on growth and feed conversion; (ii) substances with a narrow safety margin and largely reversible effects; (iii) substances with an adequate safety margin. The growth promoters (including antibiotic growth promoters) can - on the basis of their adverse effects - be classified into two groups: (i) substances with a very narrow safety margin; and (ii) substances with an adequate safety margin.

On the one hand, animal welfare considerations require use of disease-preventing additives, but on the other hand, they also demand discontinuation of current practices. Judicious use of additives can add to animal welfare. However, their unlimited use to obscure defects in husbandry is detrimental to animal welfare. A major obstacle to the judicious use of feed additives, is the lack of published, unbiased information on their efficacy and safety for farm animals.

Animals should be given the opportunity to perform behaviours that they are motivated to show if we are to maximise their welfare. Research studies into motivation and appropriate methods of studying it are therefore important. Different factors may need to be taken into consideration depending on the form of the behaviour being studied. Certain commodities, such as a perch for night-time roosting, have a value only if the animal is given full access to them until it has completed the behaviour. For other commodities, such as food and water, the amount can be varied along a continuous scale without affecting the animals’ demand for that resource. The commonly used operant techniques generating demand curves are based on the assumption that demand is not affected by the size of the reward (ie how much of the commodity the animal gains access to). As a consequence, these techniques are appropriate only for assessing motivation for resources of which the size can be varied. Resources of the ‘all-or-none’ type, on the other hand, require a different approach. We discuss different adaptations of the push-door technique as a measure of motivation, and we present results that validate a version with fixed, individually adapted levels of resistance. The method was validated using laying hens (Gallus gallus domesticus) tested at different levels of food deprivation and exposed to two series of increasing door resistances. The results show that the level of food-deprivation affects the amount of resistance that is overcome. We conclude that this method could be used to study hens’ motivation for commodities of the ‘all-or-none’ type.

The effect of an environmental enrichment — straw bales — on the behaviour of growing broiler chicks was investigated by comparing the behaviour of broilers kept in matched pairs of houses on commercial farms with and without bales. The birds provided with bales perched on them and clustered around them. The most striking result, however, was that, even away from the bales, birds in the enriched houses were more active (showing more walking and running and less sitting) than birds in unenriched houses. The study provides support for the ‘Freedom Food’ recommendation that activity in commercially kept indoor chickens can be increased by providing environmental enrichment in the form of straw bales.

Free-living hens perch on branches in trees and domestic hens (Gallus gallus domesticus) show signs of unrest if they cannot reach a perch, suggesting that night-time perching is a behaviour that hens are motivated to perform. This motivation was quantified in two experiments using a weighted push-door that hens had to push open in order to gain access to a perch. First, the motivation of individual birds to perch, and second, the effect of a companion bird on perching motivation, were measured. Eight adult laying hens (Lohmann Selected Leghorn) were trained to push through the door at increasing resistances, and the individual capacity of each hen was determined. Hens were then tested once per day, at lights-off in a test pen where pushing through the push-door gave access to the resource. Two consecutive series of increasing resistances were used in the experiment: 25, 50, 75 and 100 per cent of each bird's maximum capacity. In the first experiment, the resources offered were either a perch (treatment) or a ‘sham perch’ that could not be used for perching (control). Hens opened significantly heavier doors in order to gain access to a perch than to gain access to the sham perch. In the second experiment, pushing through the door gave access either to a perch with a companion hen already perching on it (treatment) or to a perch and a companion hen roosting on the floor (control). In this comparison, four of the hens did not push through the door, probably because of aggressive interactions with the companion, and no significant differences between treatments were found. We conclude that hens are motivated to use a perch for night-time roosting and that they should be housed in systems with perches.

Qualitative Behaviour Assessment (QBA) is a methodological approach to assess the whole animal using terms to describe and quantify the emotionally expressive qualities of behaviour and identifying larger patterns of expressivity through multi-variate statistical integration. A key condition for the success of QBA is achieving a common understanding of the meaning of descriptive terms by raters. Based on this, our study aimed to develop a list of terms in Brazilian Portuguese for the QBA of broiler chickens (Gallus gallus domesticus), and to test this list by studying its inter- and intra-rater reliability. Fourteen experts participated in a workshop and developed a list of 25 QBA terms, and 40 undergraduates tested this list by scoring 18 video clips using a 125-mm visual analogue scale. Principal Component Analysis was used to analyse observers’ scores. Principal Component (PC) 1 ranged from disturbed/frustrated to comfortable/lively, suggesting this PC may be interpreted in terms of emotional valence. PC2 ranged from calm/dull to agitated/active, suggesting this PC indicates the level of arousal/energy of the birds. Both PC1 and PC2 clip scores showed good inter- and intra-rater reliability. This study demonstrates the importance of producing QBA term lists bottom-up as opposed to merely translating pre-existing lists from the scientific literature. Results suggest the standardised Portuguese QBA term list developed in this study is reliable in assessing the expressive qualities of broiler behaviour; therefore, a next step is to test it on-farm with experienced raters and further refine it concerning terms related to poor welfare.

Analysis of post mortem lesions is a common means for assessing poultry welfare during rearing and pre-slaughter handling. The aim of this study was to determine the influence of: age, sex, rearing system, total number of birds on-farm, period between catch and slaughter and distance from poultry house to processing plant on the incidence of: foot-pad dermatitis (FPD), breast blisters (BB), bruises and scratches. Rearing systems consisted of extensive indoor (EI) and traditional free-range (TFR). Accordingly, birds were reared under non-intensive conditions (< 12 broilers m−2). In TFR, the maximum flock size was 4,800, birds had continuous daytime access to open-air runs from at least the age of six weeks, and the minimum slaughter age was 81 days; whereas EI rearing was exclusively indoor and birds were slaughtered at 56 days or later. Observations occurred daily after plucking and each bird was examined for: haematomas, scratches, FPD and BB. Logistic regressions were applied to study the relationship between variables. Farms holding between 10,000-20,000 birds were the most affected with FPD, BB and scratches. The oldest birds (91-100 days) showed the greatest incidence of FPD and scratches. TFR birds exhibited the highest prevalence of bruises and lowest of FPD. BB were most common among birds travelling between 31-60 km from poultry farm to processing plant while scratches were more frequent at greater distances (91-120 km). Male broilers were more predisposed to BB than females. Scratching increased relative to the number of hours that birds awaited slaughter. Despite the fact that only a relatively small number of broiler flocks were examined, these findings may have implications for the draft of future European legislation regarding poultry welfare.

This study sought to investigate Chinese farmers’ attitude towards animal welfare by using the Theory of Planned Behaviour (TPB). According to the TPB, an individual's intention to behave in a certain way is determined by his/her attitude towards the behaviour (specific attitude — importance — and general attitudes), the perceived behavioural control (easiness), and the supposed opinion of the people who are important to him/her (subjective norms). A total of 253 questionnaires were used, which included the three main animal productions in China (swine, poultry and cattle). Chinese farmers have perceived the improvement of animal welfare as two abstracts: general attitudes (reward-seeking, and empathic farmer); and four specific categories of actions (favourable environment, animal health, humane treatment of animals and farmers’ well-being). Our analysis revealed that general and specific attitudes were the strongest predictors of farmers’ intentions to improve animal welfare in the questionnaire study. In fact, Chinese farmers considered it fairly important to improve the animal welfare measures considered in the survey. In contrast, the same animal welfare measures were considered difficult to improve by the farmers as indicated by the lack of association between the easiness of improving animal welfare and the intentions. In addition, veterinarians, agricultural advisers, and scientific experts were considered to be relatively influential subjective norms as regards the activities of the farmers. This is the first study to provide an insight into the underlying meanings and values of Chinese farmers’ views on improvements to animal welfare.

In this study, an appropriate visual scoring system for foot-pad dermatitis was validated, considering the histologically measured depth of the inflammation zone and the histopathological grade (no lesion, mild lesion, ulcer). The aim being to evaluate whether the visual, macroscopic scoring of foot-pad dermatitis can represent the histological, microscopic findings. Two hundred Ross 308 broiler chicken feet (birds aged 39-42 fattening days) were collected at a slaughterhouse and scored macroscopically according to a modified version of the Welfare Quality® Assessment Protocol for Poultry. Afterwards, 200 histological slides (one per foot) were prepared, the extent of the inflammation measured and all slides scored by veterinarian pathologists using Michel et al's modified scheme. The statistical relationship between microscopic and macroscopic score and depth of inflammation were estimated via regression models. Increasing macroscopic score was found to be linked with an increase in microscopic score and the depth of inflammation. In particular, feet without lesions and feet with ulcers were identifiable using the macroscopic score. Macroscopic scoring of foot-pad dermatitis can mirror histological findings once certain limitations are taken into account (superficial lesions were not clearly identifiable). Foot-pad dermatitis is considered a useful indicator of animal welfare and our findings suggest that visual, macroscopic scoring could be a practicable assessment tool.

Feather-pecking and cannibalism may reduce the potential of organic husbandry to enhance the welfare of laying hens. We report risk factors for these issues based on a large survey of 107 commercial flocks in eight European countries. Information was collected regarding housing, management and flock characteristics (age, genotype). Near the end of lay, 50 hens per flock were assessed for plumage condition and wounds. Potential influencing factors were screened and submitted to a multivariate model. The majority of the flocks (81%) consisted of brown genotypes and were found in six countries. Since white genotypes (19%) were found only in the two Scandinavian countries, a country effect could not be excluded. Therefore, separate models were made for brown and white genotypes. Feather damage in brown hens could be explained by a model containing a lower dietary protein content and no daily access to the free range (30% of the variation explained). For feather damage in white hens, no model could be made. Wounds in brown hens were associated with not having daily access to free range (14% of the variation explained). Wounds in white hens were explained by a model containing not topping-up litter during the laying period (26% of the variation explained). These results suggest that better feeding management, daily access to the free-range area and improved litter management may reduce incidence of plumage damage and associated injurious pecking, hence enhancing the welfare of organic laying hens. Since this was an epidemiological study, further experimental studies are needed to investigate the causal relationships.