bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of the Halothane Gene on Pre-Slaughter Mortality in Two Spanish Commercial Pig Abattoirs
Authors: Fàbrega E , Diestre A , Carrión D , Font J , Manteca X
Published: January 2023

A total of 107 ear samples from all the pigs that died during transport or lairage at two commercial abattoirs were collected during two months (February and July), in order to determine their halothane genotype (NN, Nn or nn). The frequencies of the three halothane genotypes among dead pigs were significantly different (P < 0.001), being 4.7%, 24.3% and 71.0% for NN, Nn and nn individuals, respectively. The frequencies of pre-slaughter deaths within each genotype were estimated to be 0.02%, 0.09% and 2.29% for NN, Nn and nn genotypes, respectively. According to these results, the removal of both nn and Nn genotypes would give rise to an eleven-fold reduction in the pre-slaughter mortality rate (from 0.22% to 0.02%). It is therefore suggested that, from an animal welfare point of view, the elimination of the halothane gene in existing breeding schemes would have a major beneficial impact.
The Humaneness of Rodent Pest Control
Authors: Mason G , Littin K E
Published: January 2023

Rat and mouse control methods potentially affect the welfare of many millions of animals every year. Here, the humaneness of the methods used in the UK and the USA is assessed in terms of their speed and mode of action, the appearance and behaviour of affected animals, experiences of human victims, long-term effects on animals that survive exposure, and welfare risks to non-target animals. Several methods emerge as relatively humane: cyanide, alpha-chloralose, electrocution traps and well-designed snap traps all usually kill swiftly and with little distress. Preventative methods such as rodent-proofing are also humane, as well as an essential — and probably under-used — component of effective control. However, anticoagulant poisons, the most common means of controlling rodents, generally take several days to kill, during which time they cause distress, disability and/or pain. Sub-lethally affected animals are also likely to experience haemorrhages and their sequelae, and carnivores feeding on affected rodents may be secondarily poisoned. The acute rodenticides zinc phosphide and calciferol are also generally inhumane, the former typically causing severe pain for several hours, and the latter, pain and illness for several days. Sticky boards, to which rodents become adhered by the feet and fur until they are killed or simply eventually die, also raise very serious welfare concerns. This evidence highlights remarkable paradoxes in the way society treats different classes of animal, and argues for more education, legislation and research targeted at reducing the vast numbers of rodents currently killed inhumanely.
Telemetry as a Method for Measuring the Impact of Housing Conditions on Rats' Welfare
Authors: Krohn T C , Hansen A K , Dragsted N
Published: January 2023

Various tools have been developed over previous years to study the welfare of laboratory animals. These include preference tests, which are commonly used to evaluate housing environments. Preference tests, however, have some pitfalls: they supply information only on the animals’ present preferences, and they allow the animal the choice only between the options offered. Other methods based upon the collection of clinico-chemical data require handling of the animals, which can be stressful in itself. An alternative may be to use telemetry to measure the changes in physiological parameters caused by different environmental conditions. The aim of this study was to use telemetry to evaluate the short-term impact of housing conditions on rodents. We monitored heart rate, blood pressure and body temperature in rats kept on three different types of flooring — bedding, grid floors and plastic floors. The study revealed significant differences in systolic and diastolic blood pressure, heart rate and body temperature between rats housed in the three conditions, indicating that both grid floors and plastic floors are more stressful for the animals than bedding. The observed differences did not diminish over the two-week observation period. The grid-floor housing induced elevations in blood pressure and heart rate. Blood pressure remained elevated even when the animals were returned to standard bedding, whereas the heart rate declined back to its original value immediately in response to this shift. This study shows that telemetry is a very effective tool but that it needs integrating with other methods: in addition, a greater understanding of the biological significance of the changes in cardiovascular parameters is required before the hypothesis that these changes represent an indication of distress can be accepted.
Light, Vision and the Welfare of Poultry
Authors: Prescott N B , Wathes C M , Jarvis J R
Published: January 2023

The visual system of domestic poultry evolved in natural light environments, which differ in many respects from the artificial light provided in poultry houses. Current lighting systems are designed mainly around human vision and poultry production, ignoring the requirements of poultry vision and the functional development of visual abilities during rearing. A poor correlation between the light provided and that required for effective vision may influence visually mediated behaviours such as feeding and social interaction, leading to distress and poor welfare. To understand fully the impact of the light environment on the behaviour and welfare of domestic poultry we need (i) to measure the physical properties of the light environment in a standard and relevant manner; (ii) to identify the limits of visual abilities in various light environments; (iii) to determine how light environments during rearing may disrupt the functional development of vision; and (iv) to resolve how visual abilities and lighting interact to affect visually mediated behaviour. Some conclusions can be drawn about the impact of current lighting regimes on bird welfare but there remains a pressing need to resolve various issues in this interaction. We propose, first, that dark periods should have a minimum duration of six hours; second, that bright light should be used in cases where pecking damage and cannibalism do not pose a problem; and third, that it is unlikely that the 100 Hz flicker associated with fluorescent light can be perceived by poultry. With less certainty, we can suggest that ultraviolet-supplemented lighting may have some welfare benefits, and that very dim lighting may adversely affect ocular development. We can only speculate on other issues, such as preferences and motivations for different coloured lighting or the ways in which lighting affects recognition of conspecifics. Several organisations and authorities have issued guidelines for poultry house lighting that strive to safeguard welfare and that are consistent with our current, but limited, understanding. One omission is a standard system for measuring light levels in poultry houses. Illumination with natural daylight would be an ideal solution to many lighting problems. Although some systems require artificial lighting for production purposes, we argue that it may be possible to rear birds humanely in artificial environments that contain some features of natural light. These features should be those for which poultry show some motivation, or whose exclusion would damage visual development.
Evaluating a Concept for an Animal Welfare Assessment System Providing Decision Support Using Qualitative Interviews
Authors: Vaarst M
Published: January 2023

Qualitative interviews of farmers were carried out as part of a project focusing on developing animal welfare assessment systems (AWASs) in dairy, pig and mink production systems (26 farms in total). The aims of the interviews were to investigate farmers’ perceptions and experience of how an AWAS worked, and to explore their expectations for future use of AWASs. All interviews were taped, transcribed and analysed using a grounded-theory approach. The importance of different elements of the AWAS differed between farmers, and between farmers and the AWAS project implementation group. More direct associations between welfare assessment and production results (and other ‘common measures ‘) were requested by farmers. The whole AWAS ‘package’ was viewed as being too complex and expensive for most farmers, particularly as it involved multiple assessments over time. A range of themes emerged from the analysis. One of these, here referred to as ‘us and them’, is explored and discussed in this paper. Farmers were concerned that the AWAS could be used negatively in relation to consumers and political decisions, and they underlined that if the AWAS was to be used as a decision support tool (ie a system to assist them in making decisions about improvements in their herds and to guide their initiatives and improvements), it should include dialogue and details of local farm conditions. Qualitative interviews were found to provide valuable insight into farmers’ perceptions and expectations of animal welfare assessment methods.
Is Lameness a Welfare Problem in Dairy Farms with Automatic Milking Systems?
Authors: Klaas I C , Rousing T , Fossing C , Hindhede J , Sørensen J T
Published: January 2023

Lameness, a disease often observed in loose-housed dairy cattle herds, affects animal welfare in general and reduces cow locomotion. As cow traffic may be affected by restricted locomotion, lameness may be a significant problem in herds with automatic milking systems (AMSs). Between January and August 2002, a field study was conducted to evaluate animal health in eight herds with an AMS. Herd sizes ranged from 60 (n = 5 herds with one automatic milking unit [AMU]) to 120 cows (n = 3 herds with two AMUs). Four visits were made, during which 40-50 cows were randomly assigned for clinical examination of body condition, cleanliness, claw length, disorders of claws and legs, lameness, pressure lesions, and disorders of udder and teats. Lameness was observed in 14% of cows, ranging from 5% to 28% between herds. Approximately 60% of cows had pressure lesions on the hock and 23% of cows had overgrown claws. Preliminary results show that overgrown claws, pressure sores with swellings, early stage of lactation, and high milk yield significantly increased the risk of lameness. Lameness significantly reduced the number of voluntary milkings per day.
Husbandry and Animal Health on Organic Pig Farms in Austria
Authors: Baumgartner J , Leeb T , Gruber T , Tiefenbacher R
Published: January 2023

Expectations of retailers and consumers regarding animal health and welfare and meat quality are particularly high for organic products. The aim of this study was therefore to provide an overview of the health and welfare of pigs on organic farms in Austria. Eighty-four organic pig farms were investigated. The farmers were interviewed using a questionnaire. In addition to clinical examination, the pigs were monitored at slaughter to determine the prevalence of organ lesions. The average herd size was 20.1 productive sows in the sow units and 84 fattening pigs in the finishing units. All farms used indoor production systems and provided straw to the pigs. Pregnant sows and finishers had access to an outdoor run in more than 90% of farms, but less than 15% of farms had outdoor runs for lactating sows and weaners. In more than 75% of the herds, endoparasites were found in faecal samples. About 50% of slaughter pigs displayed milk spots on the liver, 24% had pneumonic lesions and 18% showed mange. The results indicate that preventive measures in husbandry, management and hygiene must be intensified to improve animal health and welfare on organic pig farms and to meet the expectations of the consumers.
Welfare Assessment of Working Donkeys: Assessment of the Impact of an Animal Healthcare Project in West Kenya
Authors: Leeb C , Henstridge C , Dewhurst K , Bazeley K
Published: January 2023

Development agencies and animal welfare charities try to improve the health and welfare of livestock in the developing world by educating owners and providing healthcare. The impact assessment of these projects relies mainly upon input-related parameters (eg number of animals treated or educational lectures delivered). The aim of this study was to investigate whether animal-based parameters, such as scores for skin lesions, body condition and lameness, could be used to assess the impact of interventions by development agencies on working donkeys. A general checklist for integument assessment of livestock, developed and then tested on two British farms, was redefined for assessment of equine animals in West Kenya. In total, 346 donkeys were assessed over four days with a mobile clinic of the Kenyan Society for the Protection and Care of Animals, using 25 animal-based parameters. The checklist was easy to use: the parameters could be scored using visual assessment or palpation, and the procedure was completed in approximately 5 min per animal. The method was found to be acceptable for owners and animal health technicians, and no special equipment was required. Significant observations included a reduced frequency of leg lesions when head-tethering (as opposed to leg-tethering) was used, and a reduced frequency of foot lesions in regions previously visited by the charity. This animal-based method proved that the charity had made a positive impact on donkey welfare through owner education.
Effect of amount and frequency of head-only stunning currents on the electroencephalogram and somatosensory evoked potentials in broilers
Authors: Raj ABM , O'Callaghan M
Published: January 2023

The effectiveness of head-only electrical stunning of broilers, with a root mean square (RMS) current of 100 or 150mA delivered using either 50, 400 or 1500Hz sine wave alternating current (AC), was investigated. The changes occurring in the spontaneous electroencephalogram (EEG) were evaluated using Fast Fourier Transformations (FFT) to determine the impact of the amount and frequency of stunning current on total (2-30 Hz) and relative (13-30 Hz) power contents in the EEG. Induction of epileptiform activity and reduction in the EEG power contents to less than 10% of pre-stun levels from the end of epileptiform activity were used as indicators of effective stunning. The duration of unconsciousness and insensibility was determined on the basis of the return of EEG power contents. In addition, the changes occurring in somatosensory evoked potentials (SEPs) were subjectively evaluated to determine the impact of stunning treatments. The results of ANOVA (repeated measures) showed statistically significant effects of interactions between the current frequencies, amount of current and repeated measures on changes in EEG power contents (P < 0.001). Stunning broilers with 150 mA delivered using 50 Hz resulted in EEG changes that were indicative of more pronounced neuronal inhibition following epileptiform activity and also lasted longer than was the case when broilers were stunned with 150 mA delivered using 400 Hz. Stunning broilers with 100 mA delivered using 50 Hz resulted in changes very similar to those observed after stunning with 150 mA of 50 Hz, but which lasted for a relatively shorter time. However, these changes were more pronounced and lasted longer than did stunning with 100 mA delivered using 400 Hz. The effects of stunning broilers with 150 mA of 400 Hz were similar to those found after stunning with 100 mA of 50 Hz. By contrast, stunning broilers with 100 mA of 1500 Hz failed to fulfil the criteria set out in this study. Stunning of broilers with 150 mA of 1500 Hz induced epileptiform activity but failed to reduce EEG power contents to less than 10% of pre-stun levels. Therefore, the stunning of broilers with 100 or 150 mA of 1500 Hz may not be adequate to avoid pain and suffering during slaughter. Thus, minimum currents of 100, 150 and 200 mA should be delivered whilst using 50, 400 and 1500 Hz, respectively, to achieve effective electrical stunning in broilers. Severing of the carotid arteries in the neck following head-only electrical stunning, and high frequency (> 125 Hz) electrical water bath stunning of broilers should also become a statutory requirement to prevent the return of consciousness during bleeding.
Consequences of enhancing environmental complexity for laboratory rodents — a review with emphasis on the rat
Authors: Sørensen DB , Ottesen JL , Hansen AK
Published: January 2023

Enhancing the complexity of the environments of captive animals is often referred to as environmental enrichment, and aims to have positive effects on the animals’ well-being. Such enrichments may have consequences both for so-called ‘normal’ behaviour and for the pathophysiology of the animals in question. The effects of a lack of environmental complexity, including social isolation, on home cage behaviour and on pathophysiology in rats is considered in this review. Several preference tests on rats — choice tests and operant tests — indicate a preference for bedding, nesting material and social contact. Contradictory research results concerning the need for gnawing objects per se are more difficult to interpret, and it is argued that excessive gnawing may be indicative of primary frustration and hence reduced welfare. One disadvantage of providing environmental enrichment to laboratory animals is a possible increase in subject variability, resulting in the need to use a greater number of test animals. However, this increased variability seems to be inconsistent and is not very well documented. It is argued that in cases where the behavioural benefits of environmental enrichment justify the use of more animals, better welfare should be more highly valued than a reduction in the number of animals used.
Preferences of growing ducklings and turkey poults for illuminance
Authors: Barber CL , Prescott NB , Wathes CM , Le Sueur C , Perry GC
Published: January 2023

The illuminance and spectral power distribution in 19 duckling and 16 turkey poult houses in the UK were sampled. Illuminance was highly variable within duckling houses and to a lesser extent in housing for turkey poults. In a free choice experiment, the preferences of commercial ducklings and turkey poults for four incandescent illuminances (<I, 6, 20 and 200 Ix; Osram, 60 W, Pearl) were tested at 2 and 6 weeks of age. Four replicate flocks of 12 birds were given continuous access to four compartments illuminated with each illuminance for six days. The illuminances were changed daily between the compartments. After two days of conditioning, the birds’ location and behaviour was recorded at 10 min intervals over 22 h. Nine and 12 defined behavioural categories were recorded for the ducklings and poults respectively. Ducklings spent significantly more time occupying the three brightest light environments both at 2 and 6 weeks of age, and the least time in the dimmest. Illuminance had a significant effect on the partition of behaviours amongst the light environments. At 2 weeks of age, locomotion and environmentally directed pecking occurred most often in 6, 20 and 200 lx, whereas at 6 weeks, preening and feeding also occurred more often in these light environments. At 6 weeks of age, resting, standing and drinking occurred significantly more often in 6 lx than in the dimmest environment. Turkeys spent most time in the brightest environment at 2 weeks of age, but in 20 and 200 Ix at 6 weeks. This change in overall preference was reflected in the partition of different behaviours between the light environments. At 2 weeks of age, all behaviours were observed to occur most often in 200 lx. At 6 weeks, resting and perching were observed least often in <I lx, whereas all other activities were observed more in the two brightest light environments. These results show that ducklings and turkey poults have significant but differing preferences for illuminance, and imply that some spatial or temporal variation in the ambient illuminance of housing would be consistent with their preferences.
Loose farrowing systems: challenges and solutions
Authors: Wechsler B , Weber R
Published: January 2023

The use of farrowing crates is increasingly questioned from an animal welfare point of view. Even so, since a number of attempts to develop loose farrowing systems have been unsuccessful, leading to high levels of piglet mortality due in the main to crushing, many farmers remain sceptical as to whether or not alternative systems can be viable. On the other hand, several European countries have introduced legislation requiring loose farrowing systems, thus promoting research into this type of housing and allowing for performance studies based on large samples of commercial farms. As a consequence of these recent developments, we think it timely to reconsider the evidence available on loose farrowing systems. In our review, we first address the normal peri-parturient behaviour of domestic pigs, as well as studies comparing behaviour and stress physiology in sows kept in both crates and loose systems during farrowing. We then review approaches taken to develop alternative farrowing systems in different countries, and focus lastly on pen, piglet and sow characteristics that contribute to piglet survival in loose farrowing systems. Taking scientific evidence as well as practical experience into account, we conclude that piglet mortality in loose farrowing systems need not exceed that of crate systems. To obtain good performance results, sows due to farrow should be kept individually in sufficiently large pens, structured for preference into a nest area and an activity area. Furthermore, both management and breeding aspects, resulting in high piglet viability and good maternal behaviour, are essential to achieve high production in loose farrowing systems.
Sensory development in puppies (Canis lupus f. familiaris): implications for improving canine welfare
Authors: Jones AC
Published: January 2023

Despite an auspicious start from which lasting theories were generated (eg critical periods hypothesis, Scott & Marston 1950), and despite recent modern technology enabling biological investigations of sensory development (eg EEG, fMRI), in the last fifty years little attention has been devoted to the development of puppies’(Canis lupus f. familiaris)sensory abilities. Attention to puppies’ sensory development is needed for both theoretical and applied purposes, because understanding puppies’ early experiences depends on understanding their perceptual world. This paper reviews the chronology of sensory development in puppies, looking at each sense individually. It then examines the relationships among phases of sensory and neural development and the critical periods proposed by Scott and Marston (1950). With improved knowledge and awareness of canine sensory development, researchers and other practitioners that work with puppies can better assess and improve puppies’ welfare. Therefore, this review should be of interest not only to researchers, but should also be of use to others that interact with dogs (eg shelter workers, dog breeders). By knowing what puppies are able to see, practitioners can visually enrich puppies’ environments. By knowing what puppies are able to taste and smell, practitioners can better predict the preference-related impact of introducing dietary variation to puppies. Knowing when puppies are first, and best, able to hear, see, and otherwise sense people and other animals, practitioners can design and customise programmes of socialisation and systematic exposure of young puppies.
Factors affecting time to adoption of dogs re-homed by a charity in the UK
Authors: Diesel G , Smith H , Pfeiffer DU
Published: January 2023

The objective of this retrospective cohort study was to determine the factors affecting the time until adoption of dogs re-homed by Dogs Trust, a UK charity. There were 13,338 records included in the study, representing 11,663 dogs. Data were extracted from the Dogs Trust's database between February 2001 and June 2004 representing all re-homing centres in the UK using the database during this time period. A survival analysis was conducted using Kaplan-Meier plots and multivariable Cox regression. The results of the study showed that the median time till adoption for all dogs was 28 days (95% CI 28-29 days). The variables which affected the time till adoption were breed, purebred status, size, sex, neuter status on arrival at a centre, age, coat colour, veterinary history and re-homing centre. It was suggested that temperament could be an important risk factor but this variable had to be excluded from the multivariable analysis. Dogs from the gundog and utility breed groups and purebred dogs were re-homed at the fastest rate.
The use of blended positive and negative reinforcement in shaping the halt response of horses(Equus caballus)
Authors: Warren-Smith AK , McGreevy PD
Published: January 2023

Twenty horses were paired for age, sex and breed and placed into one of two groups. The horses in Group A (control) were reinforced using only negative reinforcement (NR) while those in group B (treatment) were reinforced with both positive reinforcement (PR) and NR concurrently. All horses were shaped for the halt response while being driven in long-reins over a period of 5 consecutive days. On day I, all horses were given a baseline test of 20 random halts while being long-reined in an indoor arena. On days 2-4, the shaping of the halt response continued with horses being reinforced according to the group to which they had been allocated. On day 5 of testing the baseline test was repeated (final test). During the baseline and final tests, behavioural responses and accuracy of completion of the halt response were recorded. Heart rates were recorded continuously during testing. One-way analysis of variance in randomised blocks and analysis of covariance using baseline data as a covariate showed no effect on latency to halt. However, horses reinforced with both NR and PR shook their heads vertically less and were more likely to lick their lips than those reinforced with NR only. There was also a trend for an increase in roundness of outline of the horses that were reinforced with both PR and NR. These results suggest that the implementation of PR effectively into equitation training may improve the welfare of the horse.
The response of marine tucuxis(Sotalia fluviatilis)towards tourist boats involves avoidance behaviour and a reduction in foraging
Authors: Carrera ML , Favaro EGP , Souto A
Published: January 2023

Marine ecotourism has undergone worldwide expansion in recent years, leading to increased concern regarding the impact on the environment. Despite this, however, few studies into the potential effect of tourist boats on dolphin welfare, have been carried out. In order to evaluate the impact of these activities on the presence and foraging behaviour of the threatened marine tucuxis(Sotalia fluviatilis), we observed them: 1) prior to the arrival of a boat in the bay; 2) for the duration of a vessel's stay in the bay and 3) after the boat's departure: ie pre-exposure, exposure and post-exposure phases. Both the average number of dolphins and the foraging activity were significantly reduced while a vessel was in the bay. Marine tucuxis are exclusively coastal and show fidelity to the site where they choose to live which makes any environmental disturbance of particular importance. Moreover, our findings are further evidence of the need for motorboat activity to be regulated and monitored to protect marine tucuxis as well as other coastal and estuarine dolphins.
An assessment of laboratory mouse welfare in UK animal units
Authors: Leach MC , Main DCJ
Published: January 2023

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.
FAWC Opinion on Enriched Cages and on Beak Trimming of Laying Hens
Authors: Carter E
Published: January 2023

The UK's Farm Animal Welfare Council (FAWC) has issued two Opinions; one covering beak trimming of laying hens and the other, enriched cages for laying hens. Such ‘Opinions’ are a recent edition to the FAWC's methods for advising the Government about areas of animal welfare concern and their aim is to address specific issues in a shorter format and timeframe than traditional FAWC reports. Each Opinion provides a ‘background’ to the chosen focus followed by an ‘evidence’ and then ‘critical issue’ section. A cost/benefit ethical analysis is also included and finally an opinion, detailing the FAWC's advice and recommendations to the Government.
Assessment of unconsciousness during carbon dioxide stunning in pigs
Authors: Rodríguez P , Dalmau A , Ruiz-de-la-Torre JL , Manteca X , Jensen EW , Rodríguez B , Litvan H , Velarde A
Published: January 2023

The aim of this study was to assess unconsciousness in pigs during exposure to CO2through changes in the middle latency auditory evoke potentials (MLAEP) of the central nervous system (CNS), blood parameters (pH, carbon dioxide partial pressure [pCO2], oxygen partial pressure [pO2], oxygen saturation [SatO2] and bicarbonate [HCO−3]), behaviour and the corneal reflex. The MLEAP did not decrease significantly until after 60 s exposure to CO2. The blood parameters (decreased pH, pO2and SatO2and increased pCO2and HCO3) changed 53 s after the onset of immersion. The burst suppression index (BS%) and the A-line ARX index (AAI) from the MLEAP recovered basal levels at 136 and 249 s, respectively. The first blood parameter to return to basal levels was HCO−3at 76 s of exposure, followed by SatO2at 180 s, pH and pO2at 210 s and pCO2at 240 s. During exposure to the gas, pigs exhibited lateral head movements and sneezing (10.3 s), gasping (23.5 s) and vocalisation (26.1 s). Furthermore, all pigs demonstrated muscular excitation after between 19 and 39 s exposure, when the AAI and BS% values were not significantly different from basal values. It was suggested, therefore, that these excitatory movements represent conscious movement, indicative of aversion to the gas. According to our results, loss of consciousness began, on average, after 60 s inhalation of 90% CO2. During exposure to the gas, decreased brain activity was seen, immediately following the changes in blood parameters. Following exposure, the restoration of blood parameters to basal levels allows a return to normal brain activity.
Welfare assessment of laying hens in furnished cages and non-cage systems: assimilating expert opinion
Authors: Rodenburg TB , Tuyttens FAM , de Reu K , Herman L , Zoons J , Sonck B
Published: January 2023

It is extremely difficult to carry out an assessment of welfare in an entirely objective manner. The choice of welfare indicators, as well as the assignment of relative weightings to these indicators, both involve a certain degree of subjectivity. The aim of this study was to create a possible method of dealing with this subjectivity, using the opinions of groups of experts to increase the consensus for a protocol for the on-farm assessment of laying-hen welfare. The selection of the 17 separate welfare indicators was based both on a questionnaire submitted to 18 international poultry welfare experts and on the practical feasibility of collecting the respective data during a one-day farm visit. Subsequently, a second group of 13 experts was asked to assign relative weightings to the welfare indicators in this protocol. This assessment was carried out twice, once with and once without provision of detailed information on the welfare indicators. When detailed information was provided, the weightings assigned to the welfare indicators were generally lower than when no detailed information was provided. In conclusion, subjectivity regarding the choice of welfare indicators and the assignment of their relative weightings, can be dealt with and made transparent by seeking consensus among experts. Although the choice of experts, the methodology for extracting consensus data, and the nature and amount of information on the welfare indicators that should be provided, are likely to benefit from further refinement, the data presented in this study should be valuable for the development and application of formalised protocols for an integrated assessment of the welfare of laying hens, on-farm.
Welfare assessment of laying hens in furnished cages and non-cage systems: an on-farm comparison
Authors: Rodenburg TB , Tuyttens FAM , de Reu K , Herman L , Zoons J , Sonck B
Published: January 2023

From 2012 onwards, all laying hens in Europe will need to be housed either in furnished cages or non-cage systems (aviaries or floor-housing systems). In terms of animal welfare, furnished cages and non-cage systems both have advantages and disadvantages. Data on direct comparisons between the two, however, are limited. The aim of this study was to carry out an on-farm comparison of laying hens’ welfare in furnished cages and non-cage systems. To meet this aim, six flocks of laying hens in furnished cages and seven flocks in non-cage systems (all without an outdoor run) were visited when hens were around 60 weeks of age and a number of measures were collected: behavioural observations, fearfulness, plumage and body condition, incidence of bone breaks, bone strength, TGI-score (or Animal Needs Index), dust levels and mortality. In non-cage systems, birds were found to be more active and made greater use of resources (scratching area, perches) than in furnished cages. These birds also had stronger bones and were less fearful than birds in furnished cages. On the other hand, birds in furnished cages had lower mortality rates, lower incidence of bone fractures and lower airborne dust concentrations. When all the welfare indicators were integrated into an overall welfare score, there were no significant differences between systems. These results indicate that furnished cages and non-cage systems have both strong and weak points in terms of their impact on animal welfare.
Behavioural and Physiological Responses of Suckling Lambs to Transport and Lairage
Authors: Ibáñez M , De la Fuente J , Thos J , de Chavarri E González
Published: January 2023

The effects on stickling lambs of two stocking densities during transport (high stocking density: eight lambs per m2; low stocking density: four lambs per m2) and two periods of lairage before slaughter (1.5 h and 3 h) were studied. The behaviour of lambs transported for short-duration journeys at the two stocking densities was recorded. At slaughter, blood samples were obtained after a lairage period and some physiological parameters related to stress were analysed: lactate dehydrogenase (LDH), creatine kinase (CK), calcium (Ca2+), Cortisol, and packed cell volume (PCV). There was a significant effect of stocking density on lambs’ behaviour during transit. The number of lambs walking was greater at low than at high density (84 and 20 observations, respectively: P < 0.001) whilst the number standing was lower at low density (852 and 366 observations, respectively). There was a significant effect (P < 0.001) of stocking density on the plasma concentration of LDH. The length of the period of lairage significantly affected plasma concentrations of LDH (P < 0.001), CK (P < 0.05), Ca2+ (P < 0.001) and Cortisol (P < 0.05), as well as PCV (P < 0.01). The results show that stocking density affects the lambs’ behaviour during transport. After the longer lairage period, plasma Cortisol concentration is lower; meanwhile, the activity of LDH and CK is higher.
Stereotypic Behaviour and Tail Biting in Farmed Mink(Mustela Vison)in a New Housing System
Authors: Vinke C M , Eenkhoorn N C , Netto W J , Fermont P C J , Spruijt B M
Published: January 2023

Farmed mink are known for showing stereotypies and tail biting, behaviours that are mostly viewed as indicators of reduced welfare. Among the factors that are often described as being relevant for the welfare of mink are food management systems, age at weaning, and type/presence of nest boxes and bedding. In the present study of commercially farmed mink, all of these factors have been integrated in one housing system. The occurrence of stereotypies and tail biting were observed at six Dutch mink farms, which differed from one another with respect to the number of modifications and the time since the introduction of these modifications. On each farm, 60 non-lactating female mink were observed during winter and 50 lactating female mink (with kits) were observed during summer. Mink on the farm with the most modifications spent 4.1% and 0.8% of their time performing stereotypies in winter and in summer, respectively. Mink on the farm with the least modifications spent 32% and 10.9% of their time performing stereotypies in winter and in summer, respectively. The occurrence of stereotypic behaviour in winter gradually increased as feeding time approached. This gradual increase was not observed at the farm with the least modifications. In general, mink spent less time performing stereotypies in summer than in winter. No clear differences were found between the farms for the occurrence of tail biting in relation to the modifications of the new system, although one farm showed a lower percentage (4%) of tail biters during summer. In conclusion, the farms that had introduced more modifications into their husbandry system housed animals showing less stereotypic behaviour. The results of this field study demonstrate an inverse relationship between the number of modifications and the occurrence of stereotypies; because of the experimental design, however, a causal relationship is not implied. Further work is required to investigate the impact of each measure both in isolation and in the integrated system under more carefully standardised conditions.
A review of behavioural and physiological responses of sheep to stressors to identify potential behavioural signs of distress
Authors: Cockram MS
Published: January 2023

This paper discusses the potential for using observations of behaviour to recognise distress in sheep. The term distress is used to describe situations in which an animal is likely to be suffering, and is indicating this by overt behavioural signs. Literature on the behavioural responses of sheep to procedures that induce a physiological stress response is reviewed. This approach is based on human analogy and the assumption that physiological changes can be used to differentiate between stimuli that induce an emotional response in sheep and those that do not. The degree to which the behaviour of sheep in certain situations represents, at least in part, an expression of emotional behaviour, or whether it can be fully explained as a functional response to a specific situation, is a fundamental and unresolved question in ethological and psychological studies. Therefore, the validity of compiling a list of objective common behavioural indicators of distress in sheep will be contentious. However, it is important to be able to recognise and deal with suffering, and the use of behavioural methods for the identification of distress in sheep is a practical welfare issue. There is a need for further research to identify indicators of distress in sheep, but in the meantime it would be reasonable to make the judgement that, in some circumstances, sheep that are found to be vocalising, panting, and/or showing markedly increased locomotory activity could be experiencing distress.
Chronic stress in sheep: assessment tools and their use in different management conditions
Authors: Dwyer CM , Bornett HLI
Published: January 2023

Chronic stress occurs when animals are unable to deal with a persistent stressor with species-typical responses, or when several stressors are present concurrently. Chronic stress is most frequently considered in intensive systems, but it may also be a welfare concern for extensively managed species, such as the sheep. Here we review behavioural and physiological responses of sheep to experimentally induced chronic stressors to determine relevant indicators of chronic stress. Neuroendocrine responses to chronic stress are difficult to interpret because initial responses are followed by an apparent normalisation. Thus, cortisol or catecholamines may be at or below pre-stress levels during chronic stress, but this varies with different stressors. Chronic stress can also affect reproductive function, impair body and wool growth and meat quality, reduce immune function, and is associated with greater parasite burdens in sheep. Chronic stress induces alterations in behaviour patterns, particularly activity and feeding, and circadian rhythms of behaviour. Stereotypic behaviours, however, are infrequent in sheep and may occur only in experimental conditions of social isolation. Behavioural and physiological data suggest that rough handling and sheepdogs may be sources of chronic stress for sheep. Social subordination and weaning also act as chronic stressors, leading to higher parasitism in these animals and a greater response to additional stressors. Lameness and parasitism are associated with physiological and behavioural responses indicating that these are severe forms of chronic stress in sheep. It is unclear whether environmental stressors, such as weather and food availability, induce chronic stress in sheep. Under-nutrition may, however, be a welfare concern through its impact on lamb survival. The existence of many sources of chronic stress in the management of sheep suggests that the welfare of this species requires more attention than it has currently received.
Fox control using a para-aminopropiophenone formulation with the M-44 ejector
Authors: Marks CA , Gigliotti F , Busana F , Johnston M , Lindeman M
Published: January 2023

TheM-44 ejector (‘ejector‘) has proven to be a highly target-specific means of delivering toxicants to the exotic European red fox(Vulpes vulpes)in south-eastern Australia. Para-aminopropiophenone (PAPP) is a potent methaemoglobin (MetHb) forming compound in canids. A formulation of PAPP, dimethylsulphoxide (DMS0) and condensed milk was investigated as a new toxicant formulation for delivery by the ejector. Dosage of eight foxes in the laboratory with a sequential dose demonstrated that the formulation caused a dose-dependent and rapid elevation of MetHb. A strong inverse correlation between MetHb and oxyhaemoglobin concentrations was detected in each case. The symptoms of the toxicosis in the laboratory included progressive cyanosis, lethargy and then collapse when MetHb levels reached 56-76%. A polynomial model was a good fit for describing the relationship between sub-lethal doses of PAPP and the resulting peak MetHb levels. In a pen trial, an ejector was fitted with a bait and loaded with a standard dose of 226 mg PAPP in the same formulation and set at one end of a pen. After voluntarily triggering the ejector, all five foxes in this trial became progressively more lethargic and either lay prostrate or collapsed after 14-25 min, and death was confirmed after a mean of 43 min. We compared some clinical features of PAPP toxicosis with 15 cases of lethal sodium fluoroacetate (1080) poisoning using 0.5 mg kg-11080. PAPP produced a mean time to death that was 7.7 times faster than 1080, with the onset of first symptoms being 15 times faster. It was associated with much less activity prior to death and convulsions, spasms and paddling commonly associated with 1080 poisoning after collapse were not detected during PAPP toxicosis. We conclude that the PAPP formulation appears to be a rapidly acting and apparently humane lethal agent for fox control when used in conjunction with the ejector.
Welfare aspects of chick handling in broiler and laying hen hatcheries
Authors: Knowles TG , Brown SN , Warriss PD , Butterworth A , Hewitt L
Published: January 2023

Six commercial hatcheries were visited in the United Kingdom, three of which processed laying hen chicks and three of which processed broiler chicks. The accelerations experienced by the chicks passing through the handling systems were evaluated using miniature data logging accelerometers, which were sent through the systems. The lengths, speeds, and heights of drops of the pathways within each system were also measured. The response of the chicks to the handling was measured in terms of mortality, orientation, righting time (as a measure of disorientation) and tonic immobility. The study showed there to be a range in the physical severity of handling across the hatcheries that could also be seen in terms of differences in the measurements made on the chicks. Nonetheless, the welfare of the chicks passing through the automated systems appeared to be generally acceptable. However, given the velocities and accelerations within these handling systems, there is scope for considerable damage to the chicks, and for poor welfare, if systems are not properly set up or maintained.
Changes in ear-pinna temperature as a useful measure of stress in sheep (Ovis aries)
Authors: Lowe TE , Cook CJ , Ingram JR , Harris PJ
Published: January 2023

Activation of the sympathetic nervous system, with associated increases in heart rate and the redistribution of blood in preparation for ‘fight or flight’, is an integral part of the ‘defence reaction’. In sheep, the defence reaction involves vasoconstriction in the ear-pinna. If decreases in ear-pinna temperature (Tp) can be used to indicate vasoconstriction, then it may be possible to use changes in Tpas a measure of the defence reaction. Ewe lambs were exposed to stressors including mustering into pens, moving between pens, isolation from conspecifics, and prolonged periods of exercise. Measurements of heart rate (HR), Tp, vaginal temperature (Tv), and salivary cortisol and urinary catecholamine concentrations were used to assess stress responses. A repeatable pattern of changes in HR, Tpand Tvwas observed in response to stressors. Short-term disturbances resulted in increased HR, reduced Tp, and increased Tv. More sustained disturbances — for example, prolonged periods of exercise — resulted in a sustained elevation in HR, a sustained decrease in Tp, and a sustained elevation in Tv. The highest levels of cortisol and catecholamines were associated with the treatments that resulted in the longest periods of decreased Tp. We infer that changes in Tpoccur largely in response to changes in sympathetic nervous activity, and that the potential exists to measure elements of stress responses by monitoring Tpin freely behaving animals. This is a minimally invasive measure that allows the monitoring of modest numbers of animals over prolonged periods with minimal handling.