Animal welfare presents particular policy challenges. Good welfare provides private productivity benefits to producers and some level of positive external benefit to people who care about animal welfare status. But markets for welfare fail, meaning that private producers are unlikely to provide the correct level of external benefit and social welfare will not be maximised. Accordingly, there is a rationale for government to be involved in the provision of animal welfare. The public good nature of animal welfare supply presents policy challenges for government regulators. Specifically, in setting regulatory targets, Defra, as the regulator, aims to maximise social welfare by designing regulation that delivers benefits that are at least equal to regulatory costs at the margin. This means that regulatory targets must be informed by some assessment of benefits of welfare policies. This paper considers this problem in the context of the proposed EU Directive on broiler welfare. The paper describes the application of the contingent valuation method to measure the economic benefits of broiler welfare, and considers how the results inform welfare target setting.

The availability and complexity of escape routes are key aspects in modulating aggression. The effect of increased vertical space on the occurrence and severity of aggression was studied in a large group of chimpanzees (Pan troglodytes). Fifty wooden poles were added to the outdoor enclosure at Chester Zoological Gardens, England, UK. Connected with ropes and nets to form a complex vertical structure, they substantially increased the potential for escape routes during aggression. This study is an investigation into whether the use of the new vertical structure reduced the severity of aggression. Aggressive interactions among 29 chimpanzees (five adult males, 15 adult females, and nine immatures) were recorded whenever observed. We found that the proportion of total aggression involving the use of the vertical structure was much lower than expected based on the time individuals spent on the structure. We also found that no severe aggression was initiated when individuals were on the vertical structure. Most importantly, the proportion of severe aggression was lower when recipients of aggression moved onto the vertical structure than when they stayed on the ground. Furthermore, incidents of serious injuries were reduced after the vertical structure was added. The vertical structure appeared to function as a deterrent of aggression and an important escape route during aggressive interactions, which reduced the severity of aggression. Our results suggest that complex vertical structures are highly beneficial for semi-arboreal species with the potential for severe aggression and should be strongly considered by zoos housing such species.

There is very little known about the post-release survival of hand-reared pipistrelle bats Pipistrellus spp). We radio-tracked 12 pipistrelle bats, hand-reared and released under three different protocols: i) limited pre-release flight training and overwintering (n = 5); ii) prolonged pre-release flight training, but with limited space (n = 2) and iii) prolonged pre-release flight training in large flight cage (n = 5). Of the five bats reared under the first protocol, four were recovered, grounded, within 48 h and the signal from the fifth bat lost on day two, due either to tag failure or from the bat flying out of the study area. Both bats in the second group flew strongly on the night of release but on the second and third nights only one emerged and flew briefly. The signals from both bats remained stationary on subsequent nights. In contrast, bats from the third group were tracked for between five and ten nights, indicating that they were able to survive independently following release. These preliminary results suggest that post-release survival depends on extensive pre-release conditioning in a large flight cage, rather than the limited flight opportunities traditionally provided within domestic houses by bat carers. Other factors that may affect post-release survival are discussed and further work is encouraged to determine whether rehabilitated bats integrate with the local population.

Appropriate space allowances for animals are yet to be specifically determined for lairage. Space allowances that may be suitable for animals in lairage are suggested, based on reviewed studies of animals in transport, lairage and on farm. The longer animals are in lairage the more space they require, in order to be able to get up and lie down and lie undisturbed by congeners. Little work has been done on air quality and air flow characteristics in lairages. The range of ventilation must be sufficient to control levels of toxic or irritant gases such as carbon dioxide and ammonia and to remove excess heat and humidity; the latter being particularly relevant for pig lairages in hot weather. Intensities of sound measured in lairages often exceed 85 dB and there is evidence to suggest that such levels can be stressful especially for pigs; and human shouting appears particularly aversive to animals. Cattle vocalise in response to painful stimuli and to convey information to conspecifics that may be related to fear and distress. There is limited evidence that sheep adapt to continuous sound, provided it is not too loud, but respond to intermittent sounds such as gates banging and human shouting. Vocal communication between sheep may be less important than that between cattle and pigs. Levels of vocalisation are potential indices of animal welfare. Animals' prior experiences and factors such as sex, group size and constitution, pen design, and climatic or environmental conditions affect their welfare and responses to conditions in lairage.

Many studies on stress and pain rely, solely or mainly, on plasma Cortisol assessment. Confounding factors, such as handling, may cause a release of Cortisol making the interpretation of the results difficult. We looked at the influence of duration of restraint on the plasma cortisol levels of one-to-two month old calves. Forty-three calves were divided into four groups according to the interval between restraint and blood sampling: i) Group 0, immediate blood-sampling; ii) Group 0.5M, half a minute restraint; iii) Group IM, one minute restraint and iv) Group 2M, two minutes restraint. The only increase in plasma cortisol, compared with all the other groups, was seen with blood sampling after two minutes of restraint. This study provides evidence to suggest that cortisol released as a result of handling stress is not evident if blood sampling is carried out within one minute of restraining calves.

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.

The effects of a (30 cm high) elevated platform as an enrichment structure on the behaviour and performance of fattening rabbits kept in groups were investigated. Three housing systems for fattening rabbits were compared using a stocking density of 15 rabbits m–2. The rabbits were housed either in large pens (3.67 m2 plus a platform of 0.39 m2; with 60 rabbits per pen) or in small pens (0.503 m2 plus a platform of 0.159 m2; with10 rabbits per pen), or in conventional standard cages (0.39 m2, with 6 rabbits and without any enrichment) from 31 to 72 days of age. The conventional cages without a platform were used as a control and reference model. Rabbits housed in each small pen or in each cage belonged to the same litter, and the 60 rabbits sharing the same large pen were from six or seven litters. At the end of fattening, rabbits reached the weight of 2,508 g in cages, 2,397 g in small pens, and 2,340 g in large pens; the only significant difference was daily weight gain which was better in cages than in both pens. There was no difference in growth parameters between the two types of pens. The mortality rate was less than 1% for all treatments. No sanitation problems or severe lesions were seen with rabbits even those reared in large pens and large groups. Neither housing systems, nor elevated platform affected activities such as dietary intake or resting. The use of the platform appears to depend upon the amount of space available; in a large pen, an elevated platform can be utilised as an exercise structure while in a small pen it was used more as simply extra space to occupy.

This study investigated the effect of olfactory substances on the heart rate and lying behaviour of pigs during transport simulation. Five treatments were tested through the application of each substance to pigs’ snouts with a paintbrush. These consisted of: 1) control treatment (wiping without product); 2) 2 ml of a synthetic, maternal-like pheromone; 3) 5 ml of a synthetic, maternal-like pheromone; 4) a commercial, non-relevant odour and 5) 2 ml of a placebo (solvent of the synthetic pheromone without active ingredients). In total, 90 pigs took part in this study and each treatment was tested on a group of three pigs with six replicates per treatment. Pigs were vibrated in the vertical direction in a transport simulator with a frequency of 8 Hz and an acceleration of 3 m s−2. Cardiac activity and lying behaviour during vibration were quantified. The effect of vibration was found to be statistically significant, ie causing an increase in heart rate and numbers of ventricular ectopic beats (VEB). Both 2 and 5 ml of synthetic pheromone were generally found to decrease the minimum, mean, and peak heart rate values in comparison with the other treatments (in particular the control and the non-relevant odour group) but only minimum heart rate reached statistical significance. However, the number of VEBs was highest for these two synthetic pheromone groups during vibration. No dose-dependent synthetic pheromone effects were found and there were no differences in the amount of time pigs spent lying. The use of olfactory substances may support pigs’ ability to cope with real transport conditions thereby improving their welfare.

Two experiments were conducted to determine whether maximum eye temperature, measured using infrared thermography (IRT), could be a non-invasive technique for detecting responses of cattle to handling procedures. Experiment one used six crossbred heifers randomly assigned to two groups in a crossover design and subjected to i) being hit with a plastic tube on the rump and ii) being startled by the sudden waving of a plastic bag. Experiment two used 32 crossbred bulls randomly assigned to three treatments: i) control, restraint only; ii) electric prod, two brief applications of an electric prod or, iii) startled, as in experiment one, accompanied by shouting. Exit speed (m s−1) was recorded on release from the restraint. Maximum eye temperature was recorded continuously pre- and post-treatment. In experiment one, eye temperature dropped rapidly between 20 and 40 s following both treatments and returned to baseline between 60 and 80 s following hitting and between 100 and 120 s following startling. In experiment two, eye temperature dropped between 0 and 20 s, following both treatments, and returned to baseline by 180 s, following startling plus shouting, but did not return to baseline for five minutes following electric prod. Exit speed tended to be faster following the electric prod. In conclusion, IRT detected responses that were due possibly to fear and/or pain associated with the procedures and may therefore be a useful, non-invasive method for assessing aversiveness of handling practices to cattle.

A Delphi consultation process was used to examine the validity and feasibility of potential resource-input and animal-based outcome measures of laboratory mouse welfare identified by a comprehensive literature search. The consultation was an iterative two-stage technique that used web and email based questionnaires to gather data. On completion of the second consultation stage a total of 97 measures of mouse welfare, their order of importance, and appropriate sample sizes and sampling times where relevant, were identified. Of these, 55 were resource-input measures that included assessments of the cages, animal rooms environmental conditions, husbandry procedures, provision of food and water, staffing, resources placed into mouse cages, and the establishment policies. The remaining 42 were animal-based outcomes, measures that included assessments of unprovoked behaviour, provoked responses, vocalisations, physical appearance, and health indicators. The measures that were considered by the experts to be appropriate for assessing laboratory mouse welfare measures can be placed into four basic categories: characteristics of the staff, performance of husbandry and care procedures, health and well-being of the mice, and the provision and use of cage resources.

Tail and ear biting lesions have a negative effect both on the animal welfare status of pigs (Sus scrofus) and the economical revenue of the pig farm. Tail biting behaviour is an unpredictable, abnormal behaviour that is thought to have a multifactorial origin. On-farm factors influencing tail biting have been described, but the real triggers are poorly understood. Much of the research into tail biting has been done on a small scale within a well-controlled environment and small sample sizes. This well-controlled environment is not always representative of the contemporary commercial conditions. Therefore, an observational epidemiological approach at farm level was adopted to gain a better insight into the factors influencing the occurrence of tail and ear biting lesions. Tail and ear biting lesions were observed at pen level three times a year on sixty farms across Belgium. A questionnaire was conducted to build a multifactorial model indicating different risk factors concerning the lesions scored. The temperature and the number of feeding places per animal in the nursery, the percentage of floor space covered with slats in the farrowing unit, the feed type in the growing unit and the overall hygiene policy were the most important indicators for the appearance of tail and ear biting lesions during fattening. The leave-one-out cross validation of the model demonstrated an intraclass correlation coefficient of 0.55 between the predicted model outcomes and the observed data. This epidemiological study provides important potential risk factors in relation to the incidence of tail and ear biting lesions. However, experimental and/or longitudinal studies have to confirm that the correlations found in this work are causal factors.

A computer-based model was constructed to assess enrichment materials (EMats) for intensively-farmed weaned, growing and fattening pigs on a scale from 0 to 10. This model, called RICHPIG, was constructed in order to support the further implementation of EC Directive 2001/93/EC, which states that “pigs must have permanent access to a sufficient quantity of material to enable proper investigation and manipulation activities”. This paper describes the underlying conceptual framework for assessing EMats and explains the concepts, procedures and calculation rules used for semantic modelling. A (parsimonious) weighted average calculation rule was used to calculate enrichment scores from assessment criteria scores (which specify welfare relevant material properties of EMats) and weighting factors (WFs, which specify the relative importance of the assessment criteria). In total, 30 assessment criteria were identified and classified as object design criteria (eg novelty and accessibility), behavioural elements (eg nose, root, chew), biological functions (explore and forage), manipulations (ie object-directed behaviours), other (non-manipulative) consequences (eg aggression and stress) and object performance criteria (eg changeability/destructibility and hygiene). WFs were calculated from a systematic analysis of 573 scientific statements collected in the database, using 11 so-called weighting categories (Wcat, ie scientific paradigms to assess welfare such as the study of natural behaviour, consumer demand studies and stress-physiology) to assign Wcat level scores (which indicate the intensity, duration and incidence of a welfare impact) to the assessment criteria. The main advantages of the RICHPIG model are that it is based explicitly on available scientific information, that it has an explicitly formulated conceptual framework, is transparent, disputable, upgradeable, robust and reasonably in accordance with expert opinion. Major scope for improvements exist in the form of the need for further upgrading with new knowledge, empirical validation and (further) implementation in political decision-making processes.

Survival and mortality of extensive hill ewes are important commercial factors and valuable indicators of welfare, but difficult to study. Body condition scoring is a tried-and-tested management and monitoring tool which has been defined as a good predictor of fitness in ewes and is easily measured under hill farm conditions. This paper presents the results of a study on ewe survival rates in hill conditions in Scotland. Ewe performance and survival rates were measured in two contrasting hill flocks over a five-year period. Statistical analysis showed that mid-pregnancy body condition score was the most reliable indicator of subsequent ewe survival, followed closely by age of the ewe and environmental and management conditions. This study confirms that there are considerable welfare issues related to hill flocks and that improved winter nutritional management is a key component to good welfare and productivity. It also reinforces the view that body condition score is a good quantitative predictor of animal welfare and that poor mid-winter score indicates high risk of mortality, both at the flock and individual ewe level.

The welfare of conventional stock laboratory mice has been assessed in 46 UK animal units using an expert-defined welfare assessment protocol containing 119 measures of mouse welfare. These were recorded using a questionnaire and observations made during a one-day visit to each unit. The standard of mouse welfare was considered to be good with widespread use of substrate and nesting material and space allowances in most cases well above the minimum recommended levels. Education and training was available and encouraged by the majority of animal units. The health and welfare of laboratory mice was being frequently assessed by animal care staff using daily inspections/observations, health records, and health monitoring schemes. Overall the mice assessed could be considered to be in good health, as indicators of poor health and welfare were exhibited at low levels, and the mice were observed exhibiting a wide range of positive natural behaviours. A number of environmental conditions (humidity, noise and light intensity) were outside recommended ranges in some animal units. The provision of cage resources such as shelters, gnawing material, floor food and other enrichment items were found to be variable. A high proportion of the units surveyed housed at least some of their mice (mainly males) singly and handling of mice by care staff varied between units. In some units there may be an opportunity for some staff to improve in some aspects of mouse handling. Finally, a number of interesting correlations were found between various behaviours and potential indictors of abnormal health or welfare, which require further investigation.

The measurement of salivary cortisol allows non-invasive assessment of welfare in captive animals. We utilised this technique to test the effect of zoo opening on six Asian elephants and two Indian rhinoceros at the Terra Natura Zoological Park, Alicante, Spain, during pre-opening, opening and post-opening periods. Salivary cortisol concentrations were found to be significantly higher during the opening period than during pre- and post-opening periods for both species. This method could prove a useful tool in monitoring the success of decisions taken to improve the welfare of captive animals.

Metabolic cages are used for housing rats and mice for up to five days for collection of urine and/or faeces. The small, barren area of the metabolic cage compromises animal welfare as the animals lack a solid floor, shelter, nest material and social contact. We constructed and tested a practically-applicable enrichment device designed to meet behavioural needs for environmental complexity. The influence of this device on the cage preferences and stress levels of the animals was evaluated. A box-shaped enrichment device was designed and implemented in existing metabolic cages. Male Tac:SD rats were housed for five days in an enriched metabolic cage (EMC; n = 12) or a standard metabolic cage (SMC; n = 12), and data were collected on bodyweight, food and water intake, urination and defaecation, as well as urinary corticosterone and creatinine. Moreover, open-field behaviour and cage preferences were assessed. Rats in both groups gained significantly less weight when housed in metabolic cages. Furthermore, SMC rats failed to increase their weight gain after being housed in the metabolic cage. Defaecation was significantly higher in the SMC than in the EMC and so was urinary creatinine. No group differences were found in open-field behaviour. However, in comparing activity before and after housing in the metabolic cage, only SMC animals exhibited significantly lower total activity. In a preference test, a preference for the tunnel connecting the cages in the preference test and a side preference for the left side were found. This side preference was eliminated when the EMC was placed on the right side, whereas the right side was significantly avoided when the EMC was placed on the left side. Based on these results, we conclude that, to some extent, the enrichment device improved the welfare of rats housed in EMC, compared to those in SMC.

High concentrations of carbon dioxide (CO2), used for killing laboratory rodents, are known to be more strongly aversive to rats than sweet food items are attractive. This study investigated whether the maintenance of a high oxygen (O2) concentration, using a gas mixture of 70% CO2 and 30% O2, would reduce aversion to CO2 during a gradual-fill procedure. Eight male Wistar rats, aged 10 months, were housed individually in an apparatus consisting of two cages, one higher than the other and joined by a tube. In a series of trials, subjects entered the lower cage for a reward of 20 sweet food items. The gas was turned on at the moment the rat started eating the reward items and flowed into the lower cage at a fixed rate. There were four treatments: 1) 100% CO2 at 14.5% cage volume min–1; 2) gas mixture at 14.5% min–1; 3) gas mixture at 21.0% min–1, which delivered CO2 at approximately 14.5% min–1 and 4) air, with each subject tested with each treatment four times. Measures of willingness to stay and eat in the lower cage (latency to stop eating, latency to leave and the number of reward items eaten) were much lower in all three gas treatments than in air, indicating that the CO2 and the CO2 + O2 mixture were both more strongly aversive than sweet food items were attractive. Comparing the gas mixture with 100% CO2, the latency to leave and the number of reward items eaten were slightly higher in the CO2 + O2 mixture at 21% min–1 than in CO2 at 14.5% min–1, indicating that the addition of O2 slightly reduced the aversiveness of CO2 in the gradual-fill procedure. This reduction is not enough to warrant recommending the use of CO2 + O2 mixtures for killing rats.

The aim of this study was to investigate the combined effect of driver and driving style on the behaviour, salivary cortisol concentration, and heart-rate variability of pigs during a short journey. In addition, the effect of differing accelerations (longitudinal, lateral, and vertical) of the trailer on these variables was studied. One hundred and thirty-five cross-bred pigs (Piétrain × Hypor) were transported in groups of five on a trailer towed by a jeep. Three different drivers transported the pigs using a normal, a quiet, and a wild driving style (the latter two in relation to their normal style). Driving style mainly had an effect on the longitudinal and lateral accelerations. Salivary cortisol increases were lowest for the wild driving style. The latter can be explained by the shorter duration of these journeys and not by the accelerations, thus it is our view that acceleration due to manoeuvring as opposed to acceleration due to overall speed should be avoided. Also, in practice, journeys should take as brief a time as possible. Increasing acceleration saw an increase in the proportion of pigs standing during the journey and a decrease in the proportion of pigs lying down. Measurements of variability in heart rate revealed that lateral acceleration was an important stressor for pigs. We concluded that, as driving style has an effect on different stress variables, increased driver awareness of the effects of their driving on the responses of pigs, would improve pig welfare.

This pilot study investigates dairy heifers' perception of ‘positive treatment’ by a human (stroking and brushing) through a test of appetitive motivation. The hypothesis was that positive treatment by a human results in heifers pursuing a human to seek further positive treatment. Thirty-seven dairy heifers were assigned to either minimal human contact or positive treatment during rearing for five minutes per week, for a total of four hours, between ages six to 24 months. Six months after treatment ceased, the heifers were tested in a suite of four sequential tests, conducted while free ranging in their home pen with a group of familiar conspecifics. The tests explored whether dairy heifers that received positive treatment had: 1) a lower flight distance than controls; 2) accepted initial positive treatment during the test; and (for those who voluntarily re-approached and interacted with the human after the human had retreated) whether this was due to 3) curiosity; or 4) motivation for further positive treatment. Positive treatment heifers had a lower flight distance in component 1 of the test and more of this group voluntarily approached the human compared to the control heifers. The positive treatment allowed more initial positive treatment (component 2) and sought further positive treatment in components 3 and 4. It is concluded that ‘positive’ treatment is rewarding for many heifers. It is suggested that positive treatment constitutes environmental enrichment of dairy cattle and can enhance cattle's quality of life and the human-animal relationship.