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Interest in Equine assisted services (EAS) has grown over the past two decades, with research highlighting the benefits for participants in ridden, or mounted services. However, there is a notable lack of studies focusing on the welfare of the horses involved in these services. As research in this area continues to develop, a review is necessary to evaluate the quality of existing studies about the welfare of horses in the EAS industry. Systematic reviews provide a structured approach to organizing current literature and identifying gaps in the research. The goal of this systematic review is to summarize the existing literature on the stress and welfare of horses in EAS and pinpoint areas requiring further investigation. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, five databases were searched using terms relevant to EAS. Of the search result, 28 papers met the criteria for inclusion, requiring research to be published in English, in a peer-reviewed journal, studying EAS and its effects on equine welfare. Of the 28, 24 articles focused on quantitative data, including behavioral and physiological indicators of stress and welfare. The remaining 4 articles were survey and EAS module analysis, providing qualitative data about EAS horses. From the selected papers, we found the following trends related to EAS horse stress indicators. First, 20 (71.4 %) papers investigated physiological indicators, and 16 (57.1 %) investigated behavioral indicators. The sample size in 16 (57.1 %) articles was ten or fewer animals. The results in 17 (60.7 %) of the articles found that there was no significant difference in horses' stress or that no conclusions could be drawn regarding the horses' stress and welfare. A survey conducted by Rankins et al. (2021) revealed that the most common problems EAS centers face are behavioral and soundness issues leading to high horse turnover. Despite these findings, many studies found a lack of significant differences in their results, likely due to limitations in study design, highlighting significant gaps in the research. We also identified several inconsistent factors that are likely to affect and confound the results of EAS research. Therefore, given the limited knowledge about the welfare of horses working in EAS and the confounding factors that are likely to influence the results of studies, more robust research is needed to better understand the challenges of horses working in EAS and their welfare. • Research in Equine-assisted service horse welfare has been largely based on behavior and physiological indicators. • The most common behavioral indicators were head, ear, and tail posture. • Heart rate, heart rate variability, and cortisol were common physiological indicators. • Lack of conclusive findings on horse stress and variable research methods lead to inconsistent research conclusions. • More robust studies are required to understand horse welfare in EAS and address confounding factors. [ABSTRACT FROM AUTHOR]

The study of temperament of the order Psittaciformes has been expanding over the past decades due to the publication of papers investigating individual differences in various species. This review aimed to integrate studies on the temperament of Psittaciformes in a systematized manner, focusing on methodological aspects. It also aimed to reveal the main dimensions of temperament described for these species, identify possible gaps and suggest new themes that deserve the scientific community's attention. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was followed, and the search was conducted using Population, Intervention, and Context (PICo) terms. Three databases were used (Scopus, Web of Science, and CABI), resulting in a total of 24 publications included. The most used term to express consistent interindividual behavioral differences was 'personality' (11; 45.83 %), followed by 'temperament' (8; 33.33 %), without a clear distinction of both in this research field. Studies on temperament were conducted within the families Psittacidae (18; 75 %), Psittaculidae (4; 16.67 %) and Cacatuidae (2; 8.33 %), with the genus Amazona being the most investigated (14; 58.33 %). Regarding context, all papers used animals under human care (kept in captive environments). In total, 22 temperament dimensions were compiled, with 'boldness' (or 'shy-bold' axis or 'shyness-boldness'), 'neophobia/neophilia', 'exploration', and 'vigilance' being the most common. Quantitative methods of assessment (coding) were more commonly applied, being used in 19 (79.17 %) publications, compared to qualitative ones (rating methods). Among the factors related to temperament, pre- and post-release behavior was the most investigated (5; 20.83 %). We could conclude that studies were concentrated on a few taxonomic groups, highlighting the need to broaden the subjects studied, including other families, genera, and species. Furthermore, it would be interesting to expand the temperament evaluations into wild contexts to better understand consistent interindividual differences in parrots' natural behaviors. More efforts should be directed towards methodological and conceptual standardization, in addition to applying temporal consistency analyses. Some additional gaps that have not been studied yet include research on the genetic basis, as well as morphophysiological and neuroendocrine mechanisms underlying temperament in Psittaciformes. • A systematic review about temperament in Psittaciformes birds was conducted. • The search resulted in 24 publications, with Psittacidae and Cacatuidae families. • The most registered temperament dimensions were boldness, neophobia/neophilia, exploration, and vigilance. • Among the factors related to temperament, pre- and post-release behavior was the most investigated. • Several gaps were identified in this field of study, presenting opportunities for future research. [ABSTRACT FROM AUTHOR]

"Choice and control" is a phrase used widely in animal welfare science to describe providing captive animals with the ability to select between possible outcomes (stimuli or events). This concept has gained traction as a pivotal management technique across a variety of captive settings; however, little has been done to quantitatively evaluate choice as a welfare-improving practice. Our goal was to use a PRISMA framework to identify and review the current empirical literature on the welfare effects of choice provisions by examining measurable behavioural and biological outcomes. We evaluated choice-based studies which used an experiment design to compare choice to non-choice conditions and the impact of choice on welfare. Covidence software was used to screen and extract data from peer-reviewed literature identified across PubMed, Web of Science Advanced, and Scopus Advanced databases. Study inclusion was contingent upon a methodology which offered options for at least two or more stimuli/events given concurrently and which also contrasted a choice condition to a non-choice condition. A total of 13 papers were identified and included in this review. The majority of the papers included choices associated with enclosure access, food, and enrichment devices which resulted in improved behavioral and physiological welfare indicators across zoological, agricultural, and research laboratory settings. However, the presence of a couple papers reporting unclear or neutral impacts highlighted the need for further empirical research into the welfare impacts of choice. Increased experimental examinations with a wider range of captive settings and species are discussed and considered necessary to better comprehend the welfare benefits of providing increased choice opportunities for captive animals. [Display omitted] • Choice is considered a critical component of captive animal welfare. • We conducted a scoping review of experimental studies of choice and welfare. • Most choice studies were conducted with mammals, in zoos, and on enclosure manipulations. • Most studies showed a positive effect from a choice condition, but more research is needed. [ABSTRACT FROM AUTHOR]

Predatory behaviour is a relevant part of the behavioural repertoire of dogs, which often entails negative or desirable implications, depending on the context and target to which it is directed. It is also considered one of the most characterising aspects of breed-specific behaviour. Despite its relevance, there is surprisingly little scientific knowledge about the topic. In the present study we sought to develop an ethogram of the predatory sequence of dogs, with the aim of providing a sufficiently general structure to be applicable to dogs at large, without eluding peculiar aspects of the species' specific behaviour. Sixty videos of dogs of different breeds expressing predatory acts, including both videos obtained from public internet repositories and videos made on purpose, were described in detail by two different observers. From descriptions, a general sequence was identified, consisting of four functional phases, i.e. search, approach, chase and bite. The descriptions of the behaviours included in each phase were organised into three levels, characterised by different levels of detail and focusing on different aspects of the behaviour. When appropriate, these descriptions highlighted differences in behaviour expressed by dogs belonging to different working groups. The ethogram proposed in the present paper could represent a useful starting point for improving knowledge about the predatory behaviour of dogs and answering relevant questions about both its evolution and ontogeny. • 60 videos of dogs expressing different predatory behaviour were analysed. • The functional phases of the predatory sequence: search, approach, chase, bite. • Behaviours in each phase is organized into 3 levels of detail and behavioural focus. • Ethogram shows consistency in the sequence and breed-specific differences in phases. [ABSTRACT FROM AUTHOR]

Domestic dogs ( Canis lupus familiaris ) are versatile resources for humans due to a number of their physical and behavioural characteristics. Because of dogs’ olfactory acuity they have been used to detect cryptic or concealed items such as narcotics, explosives and wildlife. However, there is a wide variation in performance. This variation is often not correlated with their breed and has not been rigorously tested. Little research has compared dog breeds for their suitability as detection dogs, and even fewer studies have concluded which characteristics should be selected. This is important considering the number of dogs produced for detection work. This paper has collated the scientific literature to present important behavioural and physical traits, and traits which should be avoided, in detection dogs. The important traits include: highly play motivated; high level of cooperativeness with their handler; boldness; obedience yet independence when off-leash; and high athleticism. Although wildlife detection dogs are this paper’s focus, these proposed traits are relevant in any detection field. [ABSTRACT FROM AUTHOR]

Exaggerated fear-reactions are associated with injurious flying, smothering, feather pecking and other events that compromise animal welfare in laying hens. The aim of this study was to test the hypothesis that chicks with access to litter during the first five weeks of life would be less fearful as adult hens compared to birds reared without access to litter. The hypothesis was tested in a national on-farm study in commercial aviary flocks in Norway. Five rearing farmers divided the pullets into two groups within their rearing houses. While the chicks were enclosed inside the aviary rows during the first five weeks of life, paper substrate where food and other particles could accumulate, covered the wire mesh floor in the treatment group, whereas the control group was reared on bare wire mesh. At 30 weeks of age, 23 aviary flocks (11 control flocks reared without paper and 12 treatment flocks reared with paper) were visited. During the visit, the fearfulness of the adult birds was tested in a stationary person test and a novel object test. The data was analysed by ANOVA or logistic regression as appropriate. The access to litter during rearing did not influence the number of birds that approached within 25 cm of the stationary person ( p = 0.51). All flocks, regardless of rearing treatment, had birds which came within 2 m of the stationary person. The latency to approach within 2 m of the stationary person tended to be influenced by provision of environmental enrichment as adults ( p = 0.08) and by the interaction between treatment × rearing farm ( p = 0.08). The number of birds that approached within 2 m of the stationary person was influenced by the interaction between treatment during rearing and provision of enrichment as adults ( p = 0.03), however, the post hoc test showed no pairwise differences. All flocks, regardless of rearing treatment, had birds that approached the novel object. The access to litter during rearing did not influence the birds’ latency to approach the novel object. The number of birds approaching the novel object was affected by the interaction between access to substrate during rearing and provision of environmental enrichment as adults ( p = 0.05). The results indicate that both adding paper substrate to chicks from the first day of life and environmental enrichment as adults, reduce fearfulness in laying hens. [ABSTRACT FROM AUTHOR]

• Most companion cats are raised under human supervision and kept strictly indoors. • Maternal support and experience with real prey could affect hunting skills in cats. • The influence of raising and keeping conditions was tested on cats' play behaviour. • Companion cats were presented with artificial stimuli that resembles prey. • Indoor only cats showed more intense reaction than indoor-outdoor cats. Many companion cats (Felis catus) in industrialised countries are raised under human supervision and often kept completely indoors. Even if we assume that cats were not selected intentionally against hunting behaviour, we can still hypothesize that because of the differences in their epigeny and prey-related experiences, adult cats would show different willingness to engage in hunting-type behaviours. Play is considered as a useful proxy for testing predatory behaviour in cats under non-invasive conditions. We investigated the influence of raising and keeping conditions on predatory play behaviour in companion cats. We recorded the subjects' (N = 31) reactions to artificial prey-like stimuli such as balls of different sizes (latency of approach and latency of contact), catching wand (frequency of failed attempts of catching, duration of holding) and playback sound of birds, paper crumpling, plastic bags, and mice (latency and duration of search for sound source). Indoor-only cats approached, touched or played with balls sooner than indoor-outdoor cats. Indoor-only cats started searching sooner than indoor-outdoor cats for the playback sounds. Cats raised with their mother for a longer duration, had less failed attempts in catching the chaser, than subjects that were raised with their mother for a shorter duration, irrespective of the keeping condition. Indoor-only cats were more interested in the artificial stimuli that show more or less resemblance with the prey, even though these cats have been completely deprived of experience with live prey. There are various theories that can explain these findings, including higher play drive because of the lack of stimulation; less refined prey recognition; or reduced fear due to lack of experience in the indoor-only cats. [ABSTRACT FROM AUTHOR]

Undesirable companion dog behaviours negatively impact the lives of both owners and dogs. Therefore, it is imperative that behaviour modification interventions are researched to establish effectiveness. Counterconditioning is commonly recommended for modification of a broad range of undesirable dog behaviours, however, to date, no comprehensive review has investigated the effectiveness of this technique. This study aimed to evaluate the existing literature on counterconditioning interventions for dog behaviour modification, adopting broad inclusion criteria. Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 12 peer-reviewed papers and 2 dissertations were identified. A review of these 14 studies found that there were discrepancies in the definitions and applications of counterconditioning-based interventions. These discrepancies were based on the contingency with which dogs received reinforcement and could be categorised into classical and operant counterconditioning methodologies. The majority of the studies resulted in positive outcomes, particularly when addressing undesirable kennel behaviours and aggressive behaviours towards other dogs or household visitors. However, separation-related behaviours were found to be more resistant to change. Furthermore, heterogeneity in intervention techniques, reliance on expert implementation or instruction, and small sample sizes, limit the generalisability of the results. Our review confirms the effectiveness of counterconditioning in reducing undesirable dog behaviours, however it is essential that future studies clearly detail all aspects of the intervention, such that methodologies can be accurately understood, applied, and compared. Future research should also focus on increasing sample sizes and including physiological measures of stress of participating dogs. • Research investigating counterconditioning for dog behaviour modification was reviewed. • There was marked variation in the definitions and applications of counterconditioning. • These applications can be categorised as classical or operant counterconditioning. • Heterogeneity in interventions makes conclusions on effectiveness of techniques difficult. • Semantic clarity is essential in further dog behavioural intervention research. [ABSTRACT FROM AUTHOR]

In recent years, injection of clove oil was investigated as potential alternative to the use of a hot iron for disbudding due to its cytotoxic and anaesthetic properties. Isoeugenol, the isomer of the main component of clove oil, is available as a pure substance and has some advantages as compared to clove oil, but its effects were studied rarely. In this paper we investigated behaviour, heart rate, heart rate variability and surface temperature around the horn bud of 40 calves in four treatments (N = 10/treatment): injection under each horn bud of 1.5 ml clove oil (CLOV), isoeugenol (ISO) or saline (CON), or hot-iron disbudding (BURN) with local anaesthesia and sedation. Behaviour, heart rate (HR) and heart rate variability (HRV) as well as surface temperature around the horn buds were measured before and at different time points after the treatment up to 7 days post treatment; behaviour was also observed during the treatment. Behavioural observations were performed real-time or per video recording. HR and HRV were analysed during undisturbed lying periods and post-treatment changes relative to baseline were calculated. The maximum surface temperature in the region around each of the two horn buds was used for further analysis. LMM, ANOVA or, for behaviour during treatment, non-parametric tests were used for statistical analysis. There was a treatment*time point interaction (LMM, p<0.05) for behaviours associated with pain (ear flicking, head shaking, head scratching) as well as for self-grooming. HR or HRV changes from baseline did not differ between treatments, but sample size was strongly reduced due to lack of data. The development of the maximum surface temperature around the horn buds differed clearly between treatments. Our findings suggest that the injection of clove oil and especially isoeugenol causes less pain compared to the use of a hot iron without analgesia, but more pain compared to the injection of saline solution. • Clove oil or isoeugenol injection was compared with hot-iron disbudding and control • Behaviour, surface temperature and heart rate variability was recorded up to day 7 • Calves injected with clove oil played less the two days after the procedure • Hot iron disbudded calves lay shorter than clove oil or isoeugenol injected calves • Clove oil and isoeugenol injection caused less pain compared to hot iron disbudding [ABSTRACT FROM AUTHOR]

All non-human great apes are endangered, and for these animals, captive individuals play an important role in the species’ conservation management plan. Therefore, information about their current enrichment activities is essential for maintaining a healthy captive population. This paper reviews research where digital media is used as cognitive enrichment for great apes with a particular focus on orangutans, and assesses its appropriateness and relevance for current and future enrichment programs. The paper provides a holistic overview of topical issues surrounding primates in captivity, including a discussion of primate cognitive abilities, current institutional enrichment strategies and practices, and a chronological review of how digital media technologies have performed within this paradigm. The paper also covers issues in enrichment such as the concept of the power of control, natural versus non-natural enrichment, naturalism/anthropomorphism, stimulation versus stereotypy, and respecting individualism in great apes. This review reveals that as technologies advance interactive digital applications will become increasingly relevant for captive great apes and other primates because of its ability to provide improved solutions where traditional non-digital enrichment may have either failed or proven less efficient. It also highlights the importance of considering the preferences and differences in cognitive abilities of each individual when selecting particular digital enrichment activities. A wide variety of factors including life history, species, sex, age, previous enrichment experience, training routines and methods, and housing conditions will all affect the success of digital media enrichment. With this in mind, this paper identifies gaps in current knowledge, highlighting the need for further studies. [ABSTRACT FROM AUTHOR]

Captive/domestic animals are often described as inactive, with the implicit or explicit implication that this high level of inactivity is a welfare problem. Conversely, not being inactive enough may also indicate or cause poor welfare. In humans, too much inactivity can certainly be associated with either negative or positive affective states. In non-human animals, however, the affective states associated with elevated or suppressed levels of inactivity are still not well understood. Part of the complexity is due to the fact that there are many different forms of inactivity, each likely associated with very different affective states. This paper has two aims. One is to identify specific forms of inactivity that can be used as indicators of specific affective states in animals. The other is to identify issues that need to be resolved before we could validly use the remaining, not yet validated forms of inactivity as indicators of affective state. We briefly discuss how inactivity is defined and assessed in the literature, and then how inactivity in its various forms relates to affective (either negative or positive) states in animals, basing our reasoning on linguistic reports of affective states collected from humans displaying inactivity phenotypically similar to that displayed by animals in similar situations, and, when possible, on pharmacological validation. Specific forms of inactivity expressed in response to perceived threats (freezing, tonic immobility, and hiding) appear to be, to date, the best-validated indicators of specific affective states in animals. We also identify a number of specific forms of inactivity likely to reflect either negative (associated with ill-heath, boredom-like, and depression-like conditions), or positive states ( e.g. ‘sun-basking’, post-consummatory inactivity), although further research is warranted before we could use those forms as indicators of the affective states. We further discuss the relationship between increased inactivity and affective states by presenting misleading situations likely to yield wrong conclusions. We conclude that more attention should be paid to inactivity in animal welfare studies: specific forms of inactivity identified in this paper are, or have the potential to be, useful indicators of affective (welfare) states in animals. [ABSTRACT FROM AUTHOR]

Domestic animals use a varied set of strategies (behavioural- and physiological-type) to cope with aversive situations at rearing systems. Camels, although widely used as an animal model for the study of strategies to cope with heat stress and dehydration in desert-type natural habitats, remain disregarded for their coping styles in response to social stressors at man-made environments, in which they are progressively gaining presence for their sustainability traits. In this scenario, the present paper has explored the concept of coping with social stressors from a behavioral perspective in leisure dromedary camels kept at human-driven settings. By means of a multivariate statistical analysis, those animal-dependent factors that exert significant influence (p<0.05) on the type of behavioural-type coping styles (proactivity and reactivity) displayed by leisure dromedaries in response to social stressors at man-made environments have been identified. Negative reinforcement strategies, together with the use of a combination of visual and auditory stimuli, favor the proactivity in leisure dromedaries. On behalf of their condition as social species, the presence of congeners also promotes proactive coping behaviour. Sexual hormones and selection make male dromedaries more proactive as age increases, whereas this condition enhances reactivity coping responses in females. Hence, training protocols are recommended to be initiated at the earliest ages possible to reduce the probability of undesired reactivity as the animal grows and to encourage proactive attitudes as quickly as possible in females and males, respectively. However, the castration of the animals once sexual maturity is reached and domestication protocols for their functional aptitude are initiated, will stimulate not only general organic development but also proactive behaviour. With reference to body language signals, the more backward the ears are, the greater the proactivity of the camel is expected. The present results will make possible the tailoring of training protocols for leisure camels to improve the safety of human-camel interaction, valorize camels for new potential niches (i.e., assisted therapy), and enhance the list of breeding criteria for behavioral traits in these animals. • Domestication and energy-saving traits shape coping behavior in dromedaries. • Negative reinforcement and sensory cues boost camel proactivity, hence training. • Social support fosters proactive coping in dromedary camels. • Early desensitization enhances proactive engagement in dromedaries. • Backward ears indicate higher camel proactivity. [ABSTRACT FROM AUTHOR]

Tension-band castration of cattle is gaining favour because it is relatively simple to perform and is promoted by retailers of the devices as a humane castration method. Furthermore, retailers encourage delaying castration to exploit the superior growth rates of bulls compared with steers. Two experiments were conducted, under tropical conditions, comparing tension banding and surgical castration of weaner (7-10 months old) and mature (22-25 months old) Bos indicus bulls with and without pain management (ketoprofen or saline injected intramuscularly immediately prior to castration). Welfare outcomes were assessed using a wide range of measures; this paper reports on the behavioural responses of the bulls and an accompanying paper reports on other measures. Behavioural data were collected at intervals by direct observation and continuously via data loggers on the hind leg of the bulls to 4 weeks post-castration. Tension-banded bulls performed less movement in the crush/chute than the surgically castrated bulls during the procedures (weaner: 2.63 vs. 5.69, P<0.001; mature: 1.00 vs. 5.94; P<0.001 for tension-band and surgical castration, respectively), indicating that tension banding was less painful then surgical castration during conduct. To 1.5h post-castration, tension-banded bulls performed significantly (all P<0.05) more active behavioural responses indicative of pain compared with surgical castrates, e.g., percentage time walking forwards (weaner: 15.0% vs. 8.1%; mature: 22.3% vs. 15.1%), walking backwards (weaner: 4.3% vs. 1.4%; mature: 2.4% vs. 0.5%), numbers of tail movements (weaner: 21.9 vs. 1.4; mature: 51.5 vs. 39.4) and leg movements (weaner: 12.9 vs. 0.9; mature: 8.5 vs. 1.5), respectively. In contrast, surgically castrated bulls performed more immobile behaviours compared with tension-banded bulls (e.g., standing in mature bulls was 56.6% vs. 34.4%, respectively, P=0.002). Ketoprofen administration appeared effective in moderating pain-related behaviours in the mature bulls from 1.5 to 3h, e.g., reducing abnormal standing (0.0% vs. 7.7%, P=0.009) and increasing feeding (12.7% vs. 0.0%, P=0.048) in NSAID- and saline-treated bulls, respectively. There were few behavioural differences subsequent to 24h post-castration, but some limited evidence of chronic pain (3-4 weeks post-castration) with both methods. Interpretation, however, was difficult from behaviours alone. Thus, tension banding is less painful than surgical castration during conduct of the procedures and pain-related behavioural responses differ with castration method (active restlessness in response to tension banding and minimisation of movement in response to surgical castration). Ketoprofen administered immediately prior to castration was somewhat effective in reducing pain, particularly in the mature bulls. [ABSTRACT FROM AUTHOR]

Tail biting in pigs is a multi-factorial problem, and the early rearing environment has been proposed as a potential previously unidentified factor. The aim of this study was to test whether access to chewable material from birth to weaning reduces later tail biting. Undocked litters of 59 sows were allocated to two treatments. In the rope-and-paper treatment (N=30), the farrowing pens were furnished from birth to weaning with 10 pieces of sisal rope and one plastic ball suspended on the wall, and the piglets were given newspaper and wood shavings twice a day. In the control treatment (N=29), plastic ball and wood shavings were provided. The average group size was 11 piglets per pen. The piglets were weaned during week 4 after birth and transferred to growing pens, combining two or three litters from the same treatment to each pen, on average 18 pigs per pen. The growing pens were identical for both treatment groups: each had three pieces of sisal rope and a plastic chewing toy. Wood shavings were given twice a day. Behaviour was recorded on video during weeks 2, 3 and 9 after birth. Tail damage was scored during week 9. During weeks 2 and 3 after birth, oral-nasal manipulation of other piglets was less frequent in the rope-and-paper pens than in the controls (P<0.001), while oral-nasal manipulation of objects was more frequent in the rope-and-paper pens (P<0.001). Newspaper and sisal rope elicited more activity than the commercial pig ball (P=0.001). During week 9, when both treatment groups had spent five weeks in identical post-weaning environments, oral-nasal manipulation of pen mates and objects no longer differed significantly between the treatment groups (P>0.1), but there was a significant difference in tail damage. Severe tail damage (part of tail missing, or wounds with inflammation) had a mean prevalence of 9.8% in the pigs that had paper and ropes before weaning, and 32.1% in the controls (P<0.001). Mild tail damage (healed or mild lesions) had a mean prevalence of 59.2% in the pigs with early experience of paper and ropes, and 44.7% in the controls (P=0.002). In undamaged tails, there was no significant difference between the treatment groups (P>0.1). It is concluded that providing chewable materials in early life has promising potential for reducing the severity of later tail biting. [ABSTRACT FROM AUTHOR]