Validation of tests for on-farm assessment of the hen–human relationship in non-cage systems

Daylight exposure and circadian clocks in broilers: part I-photoperiod effect on broiler behavior, skeletal health, and fear response

The aim of this study was to examine effects of various daylight exposure during the 24-h light-dark (L-D) cycle on growth performance, skeletal health, and welfare state in broilers. Environmental photoperiod and related circadian clock, the 24-h L-D cycle, are important factors in maintaining productive performance, pathophysiological homeostasis, and psychological reaction in humans and animals. Currently, various lighting programs as management tools for providing a satisfactory environmental condition have been used in commercial broiler production. Four hundred thirty-two 1-day-old Rose 308 broiler chicks were assigned to 24 pens (18 birds/pen). The pens were randomly assigned to 1 of 4 thermal and lighting control rooms, then the birds were exposed to (n = 6): 1) 12L, 2) 16L, 3) 18L, or 4) 20L at 15 d of age. Lighting program effects on bird body weight, behavioral patterns, bone health, and stress levels were evaluated from d 35 to d 45, respectively. The birds of 12L as well as 16L groups, reared under short photoperiods close to the natural 24-h L-D cycle, had improved production performance, leg bone health, and suppressed stress reaction compared to the birds of both 18L and 20L groups. Especially, 12L birds had heavier final body weight and averaged daily weight gain (P < 0.05), higher BMD and BMC with longer and wider femur (P < 0.05), lower H/L ratio (P < 0.05), and more birds reached the observer during the touch test (P < 0.05) but spent shorter latency during the tonic immobility test (P < 0.05). Taken together, the data suggest that supplying 12 h as well as 16L of daily light improves performance and health while decreasing stress levels in broilers, making it a potentially suitable approach for broiler production.

How are they really doing? Animal welfare on organic laying hen farms in terms of health and behaviour

1. The present study describes the current welfare situation on commercial organic laying hen farms in Sweden in terms of indoor environment, bird health and behaviour.2. Organic laying hen farms (n = 11) in Sweden were visited for one day each. The farm visits were performed at the end of lay and involved farmer interviews, indoor environment assessments, behavioural observations and tests and clinical examinations in one flock per farm.3. In 95% of all human avoidance distance test trials performed, the hens distanced themselves from the observer before the test was completed. Median number of birds per flock approaching during a novel object test (n = 4 trials per flock) was 2 (0-9). These results may indicate a high level of fear of humans and general fearfulness among the hens.4. Plumage damage was especially prevalent and most severe on the breast and belly, tail and wings, with median prevalence of moderate-severe damage of 96% (84-100), 96% (72-100) and 98% (94-100), respectively. Median prevalence of keel bone deviations was 67% (32-84) with 3% fractures (0-8). Median prevalence of breast skin lesions was 57% (10-74). There was a significant positive association between breast skin lesions and keel bone deviations (P = 0.02) and foot pad hyperkeratosis (P < 0.001). Median prevalence of severe hyperkeratosis was 33% (8-96), with prevalence being significantly lower where litter depth was thicker (P = 0.003). More dust bathing events were observed in flocks where litter depth was thicker (P = 0.007).5. The present study contributes with updated knowledge of laying hen welfare on organic farms in Sweden. The results confirm the findings of previous on-farm studies, demonstrating that important issues, including keel bone damage and severe feather pecking, remain in need of attention to ensure the welfare of laying hens in future commercial egg production.

Fearfulness in Commercial Laying Hens: A Meta-Analysis Comparing Brown and White Egg Layers

High fearfulness in commercial laying hens can negatively affect production parameters and animal welfare. Brown and white egg layers differ in several behavioral characteristics, though reported differences in fearfulness are inconsistent. A meta-analysis was conducted to determine whether there are systematic differences in measures of fearfulness between brown and white layers. Twenty-three studies that examined either 1 or both of 2 behavioral tests were included: tonic immobility (TI) (longer duration = higher fearfulness, 16 studies) and novel object (NO) test (lower approach rate = higher fearfulness, 11 studies). The 2 tests were analyzed separately. TI analyses: A generalized linear mixed effect model (GLMM) with a lognormal distribution was fitted to describe the data with experiment nested in study as a random effect. Explanatory (X) variables were considered through backward selection, where potential X-variables included color (brown vs. white layers), decade (1980s, 2000s, 2020s), age (prelay vs. in lay), genetic stock (hybrid vs. grand-/parent stock), and methodology (back vs. side position). NO test analyses: univariable GLMMs with a beta distribution were fitted with approach rate as the Y-variable and color, decade, age, stock, or 2 methodological factors (test duration, single vs. group testing) as X-variables. Models were evaluated by assessing information criteria, residuals/random effect normality, significance of X-variables and model evaluation statistics (mean square prediction error, concordance correlation coefficient). TI duration was best explained by a color-by-decade interaction (P = 0.0006). Whites in the 1980s had longer TI durations (709.43 ± 143.88 s) than browns in the 1980s (282.90 ± 59.70 s), as well as in comparison to browns (208.80 ± 50.82 s) or whites (204.85 ± 49.60 s) in the 2020s. The NO approach rate was best explained by color (P ≤ 0.05 in 3 models), age (P < 0.05 in 3 models), and decade (P = 0.04). Whites had a higher approach rate (0.7 ± 0.07) than browns (0.5 ± 0.11), birds in lay a higher rate (0.8 ± 0.07) than birds prelay (0.4 ± 0.12), and approach rate for papers published in the 2000s (0.8 ± 0.09) was higher than in the 2020s (0.2 ± 0.12). The phylogenetic difference in the 1980s was no longer detectable after enforcing an upper limit on TI durations (10 min), as became common practice in later studies. Our findings suggest that phylogenetic differences in fearfulness and changes over time are test dependent, and this raises important questions and potential consequences for assessing hen welfare in commercial egg production.

Welfare of broilers on farm

This Scientific Opinion considers the welfare of domestic fowl (Gallus gallus) related to the production of meat (broilers) and includes the keeping of day-old chicks, broiler breeders, and broiler chickens. Currently used husbandry systems in the EU are described. Overall, 19 highly relevant welfare consequences (WCs) were identified based on severity, duration and frequency of occurrence: 'bone lesions', 'cold stress', 'gastro-enteric disorders', 'group stress', 'handling stress', 'heat stress', 'isolation stress', 'inability to perform comfort behaviour', 'inability to perform exploratory or foraging behaviour', 'inability to avoid unwanted sexual behaviour', 'locomotory disorders', 'prolonged hunger', 'prolonged thirst', 'predation stress', 'restriction of movement', 'resting problems', 'sensory under- and overstimulation', 'soft tissue and integument damage' and 'umbilical disorders'. These WCs and their animal-based measures (ABMs) that can identify them are described in detail. A variety of hazards related to the different husbandry systems were identified as well as ABMs for assessing the different WCs. Measures to prevent or correct the hazards and/or mitigate each of the WCs are listed. Recommendations are provided on quantitative or qualitative criteria to answer specific questions on the welfare of broilers and related to genetic selection, temperature, feed and water restriction, use of cages, light, air quality and mutilations in breeders such as beak trimming, de-toeing and comb dubbing. In addition, minimal requirements (e.g. stocking density, group size, nests, provision of litter, perches and platforms, drinkers and feeders, of covered veranda and outdoor range) for an enclosure for keeping broiler chickens (fast-growing, slower-growing and broiler breeders) are recommended. Finally, 'total mortality', 'wounds', 'carcass condemnation' and 'footpad dermatitis' are proposed as indicators for monitoring at slaughter the welfare of broilers on-farm.

A comparison of two manual catching methods of broiler considering injuries and behavior

The aim of this study was to compare the 2 manual catching methods in terms of injuries and behavior. Throughout 12 loadings on practical farms with the same standard, 1 container each was caught using the one-legged (1LCM) and 1 using the two-legged catching method (2LCM). The animals were filmed during loading to evaluate their behavior and subsequently examined regarding injuries. Wing flapping was observed more frequently in broilers caught with the 1LCM than 2 LCM. Carrying animals with neighbors (1 neighbor: P < 0.001; 2 neighbors: P < 0.001) and a grasping position at or above the tarsal joint (P < 0.001; P < 0.054) reduced wing flapping in both methods. A short grasping duration (P = 0.004), settling the broilers into the crate (P = 0.005) and avoiding striking the broilers against the crate (P < 0.001) reduced the occurrence of wing flapping. About 1.1% of 1LCM and 0.43% of 2LCM broilers were diagnosed with an epiphysiolysis. Catching with the 1LCM (P = 0.042), loading in lower crates (low vs. middle: P = 0.005; low vs. high: P = 0.008), a longer catching duration (p = 0.025) and female broilers (P = 0.007) had a higher chance for epiphysiolysis. Broilers loaded in lower crates (P = 0.007) and ones which showed more wing flapping (P = 0.015) had a higher chance for hematomas. A higher loading duration led to a higher risk of hematomas (prevalence: 1.5%) and a prevalence of 1.0% of broilers with severe injury in 2LCM in a simultaneously performed study (mechanical loading vs. 2LCM), in which manual loadings of entire barns were evaluated. This may be caused by fatigue of the workers. In summary, the catching method or number of grasped legs is not the decisive factor, but the compliance and implementation of the identified risks and careful handling of the animals are determining factors to reduce wing injuries caused by loading and wing flapping.

Review: Management of livestock behavior to improve welfare and production

In animal production, producers face different problems inherent to production systems. Today society is increasingly concerned about more sustainable systems and animal welfare. Applied ethology can be a tool to solve some of these problems through these approaches. The purpose of this review is to show succinctly some sustainable behavioral technologies whose application favors animal welfare and productivity. The examples cover areas of behavioral problems associated with multiple births, where odor transfer can be used to substitute or add newborns to a foster mother; early weaning, where some alternatives for a gradual break may reduce the stress of separation; early experience on the development of food preferences, where behavioral problems like neophobia can be avoided; early detection of sick animals, where recognition of some specific behaviors could help early identification of diseases, even before the appearance of clinical signs; social isolation on ease of handling, where different techniques have proved their effectiveness modifying the temperament of the animals; design of facilities and management, where it is highlighted how when considering the behavior of the animals in the design and management, better results are obtained; social isolation, facilitation, and buffering, where the presence of other members of the group can modify the consumption and sexual behaviors of pen-mates, or even alleviate suffering; and human-animal interaction on productivity, where the relevance of a positive human-animal interaction is highlighted. After reviewing the scientific literature on the subject, we can conclude that several modern livestock management practices might induce stress in animals, affecting their welfare, health, and productive performance. Applied animal behavior could be a sustainable and effective option to understand and solve some of these problems, and in many cases does not even require a strong economic investment for producers.

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 a partially perforated flooring system on animal-based welfare indicators in broiler housing

Alternative flooring designs in broiler housing have been the subject of intensive research. Research comparing different floor types with a focus on animal-based welfare indicators might be of special interest to meet the animal's needs. This case-control study investigated the effect of a partially perforated vs. a littered flooring system on health- and behavior-based welfare indicators of fast-growing Ross 308 broilers. Furthermore, production performance was assessed. The experimental barn was partially (50%) equipped with a perforated floor directly underneath the feeders and water lines accessible by perforated ramps. Conventional wood shavings were used in the control barn, as usual in practice. There were 4 fattening periods (repetitions) of 31 to 32 D performed with 500 animals per barn (final density of 39 kg m-2). Beside the flooring system, management conditions were identical. Health- and behavior-based welfare indicators were assessed weekly. Production performance indicators were measured continuously during animal control. During the avoidance distance test, animals were less fearful on day 21 (P = 0.010) and tended to be less fearful on day 28 (P = 0.083) in the barn with the partially perforated flooring system compared to the littered control barn. More animals around the novel object were also assessed in the barn with the partially perforated flooring system during the novel object test on day 1 (P < 0.001) and a tendency was found on day 28 (P = 0.064). Results showed that the partially perforated flooring system had a positive influence on foot pad dermatitis from day 14 (all P ≤ 0.007) and hock burn on day 28 (P < 0.001). With regard to the production performance, animals showed no differences in final body weight for both floor types. In this study, the partially perforated flooring system had a positive effect on animal health and behavior as indicated by welfare indicators without a reduction in production performance.

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

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.

A novel environmental enrichment device increased physical activity and walking distance in broilers

Modern broilers are selected for fast growth and a large proportion of breast tissue, contributing to a top-heavy phenotype, leg disorders, and inactivity as birds reach market weight. Therefore, the objective was to motivate broilers to move through environmental enrichment. A total of 1,200 Ross 308 broilers were housed in pens of 30 for 6 wk: 600 birds were exposed to a novel laser enrichment device (LASER) and 600 were control. Each device projected 2 randomly moving red laser dots onto the floor 4 times/day for 4-min "laser periods." Seven LASER and 7 control pens, with 5 focal birds/pen (n = 70), were randomly selected to be video-recorded day 0 to 8 and once weekly for the remainder of the trial. Videos were analyzed to measure broiler time-budget and behaviors such as latency to feed and distance walked during laser periods. Focal birds were gait scored weekly on-farm. A test of the human-approach paradigm was carried out on weeks 1 and 6 on all pens. LASER birds were more active on days 0, 1, 3, 4, 5, 7, and 8, moving 254% more on day 7 (P ≤ 0.05). Time spent active was increased in LASER treatment by 114% on week 2; 157% on week 3; 90% on week 4; and 82% on week 5. LASER birds spent more time at the feeder on days 0, 1, 2, 5, 8, and on weeks 1 and 5, with 84% more time at feeder than control on day 5 (P ≤ 0.05). LASER birds walked further during laser periods on day 0 to 8, reaching 646.5 cm greater (day 1), and on weeks 2, 3, 4, and 5, with an increase of 367.5 cm on week 2 (P ≤ 0.05). Over week 1 to 6, 60.54 ± 7.4% of focal birds in the laser treatment were at the feeder during or within 5 min following laser periods. The laser enrichment device was successful in stimulating broiler physical activity and feeding, and did not negatively impact walking ability.

Development and Validation of Broiler Welfare Assessment Methods for Research and On-farm Audits

Required auditing of on-farm broiler welfare in the United States has increased; however, a lack of validated tools exists for assessment of enrichment. National Chicken Council (NCC) guidelines were used on a subset of 300 Ross 308 broilers out of 1200 to validate and adapt welfare measures. Half of the broilers were exposed to environmental enrichment, hence these measures were used to evaluate the enrichment within the context of behavior and welfare, although the nature of the enrichment is not described in detail here as the aim is to serve solely as a description and validation of methods using a subset of example data. Birds were recorded in repeated 4-min periods to quantify behavior and walking distance. Outcomes were categorized to improve auditing and make recommendations to producers and researchers. Bone mineral density, content, and breaking strength were successful in determining numerical differences. Quantifying lameness using an enclosed walkway and measuring footpad dermatitis weekly are recommended on-farm. We recommend including additional measures not required by the NCC: monitoring breast condition in the flock and including a behavior component with a scoring ethogram.

Effects of different floor materials on the welfare and behaviour of slow- and fast-growing broilers

Litter quality and fast growth rate are the two main issues in broiler welfare. This study aimed to evaluate the effects of genotype and floor material on broiler welfare and behaviour. In the study, slow-growing (Hubbard JA57) and fast-growing (Ross 308) broilers on a slatted floor and deep litter were used; there were four main groups (2 genotype  ×  2 housing) and each treatment group consisted of 5 replicates. Each replicate group consisted of 10 male chicks, and 200 birds were used in total. The experiment lasted for 8 weeks. The welfare parameters were recorded in weeks 6, 7, and 8, whereas behaviour data were collected in week 8 only. Results showed that welfare parameters of broiler chickens were affected by genotype and floor type. Slow-growing broilers had better welfare parameters than fast-growing broilers. The slatted floor had a positive effect on main welfare parameters of the birds. Slower-growing broilers had a longer distance in the avoidance distance test. Tonic immobility reaction was longer in slow-growing broilers compared to fast-growing broiler. On the other hand, floor type did not affect behaviour parameters. As a conclusion, slow-growing broilers had better welfare parameters than fast-growing broilers and slat flooring could be beneficial to improve broiler welfare, but further behavioural investigations are needed such as dust bathing and walking behaviour.

Effect of Two Transport Options on the Welfare of Two Genetic Lines of Organic Free Range Pullets in Switzerland

Simple Summary

Animal welfare has been of increasing interest to consumers and producers of animal products in Europe. Issues during transport affect both the wellbeing and the productivity of livestock. This study was conducted to analyze two practice-oriented transport variants of organically mixed-held white and brown pullets. No significant difference could be found between the transport variants. Instead, we discovered clear differences between the two genetic pullet lines.

Abstract

The welfare of two genetic lines of organic layer hen pullets—H&N Super Nick (HNS) and H&N Brown Nick (HNB)—was compared during two commercial transport variants of 15 flocks of mixed-reared birds. Birds were either transported overnight (with a break in travel), or were transported direct to the layer farm (without a break in travel). Samples of feces were collected non-invasively from 25 birds of each genetic line per flock for each transport variant before transportation to evaluate baseline values of glucocorticoid metabolites, and at 0 h, 3 h, 6 h, 10 h, 24 h, 34 h, 48 h, 58 h, and 72 h after the end of transportation, to measure transportation and translocation stress. We assessed the fear toward humans with the touch test before transportation, and we checked the birds’ body condition by scoring the plumage condition and the occurrence of injuries. Body weight before and weight loss after transportation were determined, and ambient temperature was measured before, during, and after transportation. Stress investigations showed no significant differences between the transport variants (effect: −0.208; 95% confidence interval (CI): (−0.567; 0.163)). Instead, we discovered differences between the pullet lines (effect: −0.286; 95% CI: (−0.334; 0.238)). Weight loss was different between the transport variants (2.1 percentage points; 95% CI: (−2.6; −1.5)) and between the genetic lines, as HNB lost significantly less weight than HNS (0.5 percentage points; 95% CI: (0.3; 0.7)).

Effects of two different broiler flooring systems on production performances, welfare, and environment under commercial production conditions

Research comparing conventional litter and alternative perforated flooring (netting) systems is relatively limited under commercial production conditions. A comprehensive comparison of broiler production performances, welfare quality, and housing environment of two broiler houses with conventional litter and new perforated plastic floors was conducted over four flocks for eight months in eastern China. The two broiler houses each had 31,700 broilers per flock on average and were ventilated using a negative-pressure system. Prior to the onset of the monitoring, litter/manure in all houses was removed. The environmental conditions, gaseous concentrations, and ventilation rate were recorded continuously. Production performance and welfare quality data were collected weekly. Results showed that indoor temperature and relative humidity were not affected by the different floors when the two houses had the same ventilation configuration and management. The average ammonia concentration was lower at 10.44 ppm in the litter house compared to 15.02 ppm in the netting flooring house due to the manure accumulation under the floor. Broiler production performance including live weight, feed conversion, and mortality, was not affected by the netting floor compared to the litter system. In addition, the results suggested that birds raised in the netting floor house may increase breast blister incidence. In this study, the welfare quality parameters including hock and foot pad lesions, lameness, and fearfulness levels were similar in both for both flooring systems.

Lameness assessment with automatic monitoring of activity in commercial broiler flocks

The possibility of using automatic recordings of broiler chicken activity in commercial flocks to assess the birds΄ walking ability (lameness) was investigated. Data were collected from 5 commercial broiler farms in 4 European countries, using 16 flocks and 33 assessment occasions. Lameness was assessed using established gait scoring methods (Kestin et al., 1992; Welfare Quality®, 2009) and took place at 3, 4, and 5 wk of age. Gait score (GS) was used to assess the birds' walking ability, and automatic recordings of bird activity were collected using the eYeNamic™ camera system before, during, and after an assessor walked through the house. The variables used to predict the level of GS extracted from the camera system were: baseline activity, time from assessor leaving the house to resumption of baseline activity, average activity over that period, and Δ Amplitude (difference between highest activity peak after assessor left the house and baseline level). Age (<0.001) and Δ Amplitude (P = 0.0002) were significantly related to GS, with the gait getting poorer with increased age and Δ Amplitude decreasing with declining walking ability. Both measures are thus included in a predictive equation. The results demonstrate a potential method using image analysis techniques to realize an automated assessment of the level of lameness in commercial broiler flocks. This could be of use in future animal welfare assessment schemes.

Play behaviour, fear responses and activity levels in commercial broiler chickens provided with preferred environmental enrichments

There is currently a lack of research investigating the effectiveness of commercial broiler enrichments, and in particular the ability of these additions to create opportunities for positive welfare. One aim of this study was to investigate whether offering broiler chickens enrichments that have recently been found to be preferred leads to increased levels of activity. A second aim was to investigate the emotional effects of provision of these enrichments by assessing levels of fearfulness and play-like activity. Commercially housed broilers were assigned to treatment houses containing either: (1) platform perches, (2) platform perches+peat dust baths, (3) no enrichment (control). Activity levels and play behaviours in unenriched areas of the house were measured in weeks 3, 4 and 5. Levels of active behaviours, such as foraging and locomotion, were determined from video recordings of undisturbed birds in unenriched areas of the house. To stimulate play-like behaviours an observer walked through the birds, displacing them and creating a space. The broilers using the space were then filmed for 5 min and the occurrences of frolicking, sparring and food-running were recorded. Fearfulness of broilers in unenriched areas of the house, and also when using enrichments, was measured using observer avoidance tests in week 5. We found that creating space among the broilers was a successful method of stimulating play (largely sparring and frolicking), with play being observed in 93% of videos, however the presence of enrichments did not have an effect on the level of play recorded (P&gt;0.05). There was also no treatment effect on activity levels of broilers in unenriched areas (P&gt;0.05), however levels of overall activity decreased as broilers aged. Compared with the control, flight distances in unenriched areas were significantly lower in the perches+dust bath treatment (P=0.026), and were numerically lower in the perches treatment. This suggests a reduction in fearfulness with increased environmental complexity, and thus possible welfare benefits. It is suggested that further research should investigate whether increasing the level of provision of these enrichments leads to more marked improvements in welfare.

The relationship between measures of fear of humans and lameness in broiler chicken flocks

In the Welfare Quality® assessment protocol for broilers, the touch test is included to assess the human-animal relationship in the flock. The test is designed to measure the animals' fear of humans, assuming that broilers will withdraw from the observer if they are fearful. However, many broilers close to slaughter age have impaired walking ability, and the results from the touch test may thus be biased by lameness and poor leg health. As the touch test is currently being used in several countries to assess human-animal relationship in broilers, there is an urgent need to examine this potential relationship for a further validation of the test. In the present study, fear of humans was assessed in 50 randomly selected Norwegian broiler flocks, using the touch test as described in the Welfare Quality® protocol for ty broilers. Leg health was assessed by examining the gait of 150 random birds in each of the flocks, using a six-point gait score scale from 0 to 5. The coefficient for the relationship between touch test score and gait score was 0.034 (P<0.001), indicating that the animals express less fear as assessed by the touch test when the gait scores increase. This implies that the touch test may be confounded by impaired walking ability and therefore might be a suboptimal method of assessing fear of humans and human-animal relationship in broilers. In conclusion, the results from this study suggests that the touch test must be further validated in broilers and perhaps be replaced with a fear test that doesn't rely on walking ability.

Potential risk factors associated with contact dermatitis, lameness, negative emotional state, and fear of humans in broiler chicken flocks

The objectives of this study were to 1) identify determinants of poor welfare in commercial broiler chicken flocks by studying the associations between selected resource-based measures (RBM, potential risk factors), such as litter quality and dark period, and animal-based welfare indicators (ABM), such as foot pad dermatitis and lameness, and 2) establish the breadth of effect of a risk factor by determining the range of animal welfare indicators associated with each of the risk factors (i.e., the number of ABM related to a specific RBM). Eighty-nine broiler flocks were inspected in 4 European countries (France, Italy, the United Kingdom, and the Netherlands) in a cross-sectional study. The ABM were contact dermatitis (measured using scores of foot-pad dermatitis and hock burn, respectively), lameness (measured as gait score), fear of humans (measured by the avoidance distance test and the touch test), and negative emotional state (measured using qualitative behavior assessment, QBA). In a first step, risk factors were identified by building a multiple linear regression model for each ABM. Litter quality was identified as a risk factor for contact dermatitis. Length of dark period at 3 wk old (DARK3) was a risk factor for the touch test result. DARK3 and flock age were risk factors for lameness, and the number of different stockmen and DARK3 were risk factors for QBA results. Next, the ABM were grouped according to risk factor and counted. Then, in a second step, associations between the ABM were investigated using common factor analysis. The breadth of a risk factor's effect was judged by combining the number (count) of ABM related to this factor and the strength of association between these ABM. Flock age and DARK3 appeared to affect several weakly correlated ABM, thus indicating a broad range of effects. Our findings suggest that manipulation of the predominant risk factors identified in this study (DARK3, litter quality, and slaughter age) could generate improvements in the related ABM and thereby enhance the birds' overall welfare status.

Programmatic approaches to assessing and improving animal welfare in zoos and aquariums

There continues to be intense public, professional, and scientific focus on the welfare of animals in zoos and aquariums, but implementing welfare assessment tools consistently throughout this community remains challenging. Indirect measures can be used to assess "welfare potential"-the potential that animals will experience good welfare based on the care that they are provided with. Zoos and aquariums focus on welfare potential with their continued commitment to develop animal care guidelines (e.g. Animal Care Manuals) that can play a role within institutional accreditation or certification. The Association of Zoos and Aquariums Animal Welfare Committee has been pursuing approaches to maximize welfare potential by developing the concept of an integrated welfare approach or framework-an attempt to identify recommended animal care programs (e.g. enrichment, nutrition, veterinary care, research, and animal training programs) and their programmatic components. Objectively assessing the influence that animal care recommendations have on the welfare of individual animals is important to determine the efficacy of programmatic approaches. The future of welfare assessment within zoos and aquariums will include population-level evaluations-tracking emerging trends in health and behavior that come from both formal and informal institutional animal reports. Sharing this information, and performing meta-analyses of the data using epidemiological approaches, will become easier with advances in technology and database management software. Identifying welfare "red/green flags" throughout captive populations will provide direction for more focused assessments that will ultimately inform the design of more effective animal care programs.

Inter-observer and test-retest reliability of on-farm behavioural observations in veal calves

The objective of this study was to investigate inter-observer and test-retest reliability of different behavioural observations to be used in an on-farm, animal welfare monitoring system for veal calves. Twenty-three veal calf farms, varying in size, housing system, feeding regime and age of the calves were visited twice with two observers, simultaneously. Behavioural tests were conducted in eight pens per farm, measuring the response of calves to: a human entering the barn; a novel object; a passive, unfamiliar person; disturbance in the pen and an active approach by an unfamiliar and a familiar person. Furthermore, behaviour was recorded 20 min before and 20 min after feeding in eight other pens per farm. For all behavioural tests, inter-observer reliability was very high. Farm effects and test-retest reliabilities were high and significant for all behavioural tests, except for the test measuring response to disturbance in the pen. Although the active approach test with the familiar person was reliable, it was not feasible in practice due to the availability of the farmer. Since the active approach test with the unfamiliar person gave similar results, this test was recommended for an on-farm animal welfare monitoring system. For most behavioural elements recorded around feeding, farms differed significantly and interobserver and test-retest reliabilities were high as well as being significant. The behavioural tests with entering the barn, novel object and unfamiliar person, and the behavioural observations before and after feeding were feasible and distinctive and reliable enough to be performed on-farm. These methods are promising tools to use as a monitor of animal welfare in veal calves.