• Conceptual and methodological issues relating to pain assessment in mammals: the development and utilisation of pain facial expression scales.

      McLennan, Krista M.; Miller, Amy, L.; Dalla Costa, Emanuela; Stucke, Diana; Corke, Murray J.; Broom, Donald M.; Leach, Matthew C.; University of Chester; Newcastle University; c Università degli Studi di Milano; Havelland Equine Clinic; University of Cambridge (Elsevier, 2019-06-12)
      Effective management of pain is critical to the improvement of animal welfare. For this to happen, pain must be recognised and assessed in a variety of contexts. Pain is a complex phenomenon, making reliable, valid, and feasible measurement challenging. The use of facial expressions as a technique to assess pain in non-verbal human patients has been widely utilised for many years. More recently this technique has been developed for use in a number of non-human species: rodents, rabbits, ferrets, cats, sheep, pigs and horses. Facial expression scoring has been demonstrated to provide an effective means of identifying animal pain and in assessing its severity, overcoming some of the limitations of other measures for pain assessment in animals. However, there remain limitations and challenges to the use of facial expression as a welfare assessment tool which must be investigated. This paper reviews current facial expression pain scales (“Grimace Scales"), discussing the general conceptual and methodological issues faced when assessing pain, and highlighting the advantages of using facial expression scales over other pain assessment methods. We provide guidance on how facial expression scales should be developed so as to be valid and reliable, but we also provide guidance on how they should be used in clinical practice.
    • Development of an Automated Pain Facial Expression Detection System for Sheep (Ovis Aries).

      McLennan, Krista M.; Mahmoud, Marwa; University of Chester; University of Cambridge (MDPI, 2019-04-25)
      Detecting signs of pain in sheep is a challenging problem, as they are a prey species and would usually try to hide any signs that they are unwell or injured. This means that treating ill or injured sheep and preventing any further spread of contagious diseases such as footrot can be slow. The recent development and publication of a Sheep Pain Facial Expression Scale (SPFES) has provided a tool to reliably detect pain in this species. However, due to the increase in intensification in farming and larger flock sizes being cared for by individual farmers, there is less time to spend monitoring sheep for changes in behaviour that may indicate illness or injury. Having an automated system that could detect changes in the facial expression of individual sheep would mean that farmers could receive information directly about particular individuals that need assessment. This would allow treatment to be provided in a timely and direct manner, reducing suffering. We have been developing the SPFES further in order for it to become an automated system. In this paper, we present our novel framework that integrates SPFES concepts with automatic facial expression analysis technologies.
    • Improving the practicality of using non-aversive handling methods to reduce background stress and anxiety in laboratory mice

      Gouveia, Kelly; Hurst, Jane; University of Liverpool; University of Chester
      Handling can stimulate stress and anxiety in laboratory animals that negatively impacts welfare and introduces a confounding factor in many areas of research. Picking up mice by the tail is a major source of handling stress that results in strong aversion to the handler, while mice familiarised with being picked up in a tunnel or cupped on the open hand show low stress and anxiety, and actively seek interaction with their handlers. Here we investigate the duration and frequency of handling required for effective familiarisation with these non-aversive handling methods, and test whether this is sufficient to prevent aversion and anxiety when animals then experience immobilisation and a mild procedure (subcutaneous injection). Very brief handling (2 s) was sufficient to familiarise mice with tunnel handling, even when experienced only during cage cleaning. Brief but more frequent handling was needed for familiarisation with cup handling, while pick up by tail induced strong aversion even when handling was brief and infrequent. Experience of repeated immobilisation and subcutaneous injection did not reverse the positive effects of tunnel handling. Our findings demonstrate that replacing tail with tunnel handling during routine cage cleaning and procedures provides a major refinement with little if any cost for familiarisation.
    • Measuring physiological stress in the common marmoset (Callithrix jacchus): Validation of a salivary cortisol collection and assay technique

      Ash, Hayley; Smith, Tessa E.; Knight, Simon; Buchanan-Smith, Hannah M.; University of Stirling; University of Chester; Defence Science and Technology Laboratory (Dstl); University of Wisconsin (Elsevier, 2017-12-15)
      Cortisol levels are often used as a physiological measure of the stress response in captive primates, with non-invasive measures of this being an important step in welfare assessment. We report a method of collecting saliva samples voluntarily from unrestrained captive common marmosets (Callithrix jacchus), and validate an enzyme-linked immunosorbent assay (ELISA) technique previously unused in this species. Saliva samples were collected from marmosets housed in pairs in a UK laboratory. The assay showed parallelism, precision, accuracy and sensitivity, meeting the criteria typically used to investigate the effectiveness of new analytical techniques. Use of Salimetrics® Oral Swabs considerably increased the amount of cortisol recovered in comparison with previous studies using cotton buds. However, while use of banana on the swabs can encourage chewing, it may influence results. Although increases in cortisol levels have traditionally been interpreted as an indicator of stress in primates, there are many factors that affect the hypothalamic-pituitary-adrenal axis, with some studies showing decreases in cortisol levels post-stressor. Following a likely stressful event (capture for weighing), we also found cortisol levels significantly decreased, possibly due to social buffering or ‘blunting’ of the HPA axis. Order of weighing also had an effect. The method therefore provided an effective non-invasive means of assessing acute changes in cortisol level that may be more useful than previous methods, improving our ability to study physiological aspects of welfare in primates. We discuss methodological considerations, as well as implications of using cortisol as a measure of stress.
    • Patterns of behaviour, group structure and reproductive status predict levels of glucocorticoid metabolites in zoo-housed ring-tailed lemurs, Lemur catta.

      Smith, Tessa E.; McCusker, Cara; Stevens, Jeroen M. G.; Elwood, Robert W.; University of Chester; Queens University of Belfast; Centre for Research and Conservation, Royal Zoological Society of Antwerp, Belguim (Karger Publishing, 2016-01-30)
      In ring-tailed lemurs, Lemur catta, the factors modulating hypothalamic-pituitary-adrenal (HPA) activity differ between wild and semi-free-ranging populations. Here we assess factors modulating HPA activity in ring-tailed lemurs housed in a third environment: the zoo. First we validate an enzyme immunoassay to quantify levels of glucocorticoid (GC) metabolites in the faeces of L. catta. We determine the nature of the female-female dominance hierarchies within each group by computing David’s scores and examining these in relation to faecal GC (fGC). Relationships between female age and fGC are assessed to evaluate potential age-related confounds. The associations between fGC, numbers of males in a group and reproductive status are explored. Finally, we investigate the value of 7 behaviours in predicting levels of fGC. The study revealed stable linear dominance hierarchies in females within each group. The number of males in a social group together with reproductive status, but not age, influenced fGC. The 7 behavioural variables accounted for 68% of the variance in fGC. The amounts of time an animal spent locomoting and in the inside enclosure were both negative predictors of fGC. The study highlights the flexibility and adaptability of the HPA system in ring-tailed lemurs.
    • Technical note: Validation of an automatic recording system to assess behavioural activity level in sheep (Ovis aries).

      McLennan, Krista M.; Skillings, Elizabeth, A.; Rebelo, Carlos J. B.; Corke, Murray J.; Pires Moreira, Maria A.; Morton, A. Jennifer; Constantino-Casas, Fernando; University of Cambridge; Universidade Federal Rural do Semi-Arido (Elsevier, 2015-06-01)
      The welfare of an individual can be assessed by monitoring behavioural changes, such as inactivity, that may indicate injury or disease. In this study we validated the Actiwatch Mini® activity monitor (AM) for automatic recording of behavioural activity levels of nine Texel ewes. The AM devices were attached to collars placed around the necks of the ewes. AM recordings were taken at 25 second intervals for 21 consecutive days and in addition, direct behavioural observations made on days 9 to 13. AM recordings were compared with direct behavioural observations to investigate whether different levels of behaviour activity could be distinguished by the AM. Six different behaviours were matched to the activity scores recorded by the AM which were low activity (lying ruminating, lying), medium activity (standing, standing ruminating, and grazing) and high activity behaviours (walking). There were differences in the activity scores for all three scores. However, higher levels of accuracy in distinguishing between activity levels were achieved when combining high and medium activity level behaviours. This method of capturing data provides a practical tool in studies assessing the impact of disease or injury. For example, assessing the effects of lameness on the activity level of sheep at pasture, without the presence of an observer influencing behaviour.
    • Zoo-housed mammals do not avoid giving birth on weekends

      Hosey, Geoff; Ward, Samantha J; Ferguson, Amanda; Jenkins, Hannah; Hill, Sonya P; University of Bolton; Nottingham Trent University; ZSL London Zoo; North of England Zoological Society; University of Chester
      There is evidence that zoo visitor presence can influence the behavior and, in some cases, adrenal response of zoo animals, and can sometimes compromise animal welfare. In some laboratory studies, significantly more primate births have been reported on weekends, when fewer people are working there, compared with weekdays when staffing levels are at their highest. Here we investigate whether there is evidence of a “weekend effect” on births in zoo animals as a result of visitor numbers. Unlike laboratories, zoos are typically busier with visitors on weekends than on weekdays, although staffing levels remain fairly consistent across days of the week. If zoo animal parturition is sensitive to human presence, then fewer births would be expected on weekends compared with weekdays. We tested this using birth data and visitor numbers on the entrance gate from zoo records across 16 species representing artiodactyls, perissodactyls, carnivores and primates at four British zoos, to see whether there is an association between mean daily birth rates and average visitor numbers. We predict that, if there is a visitor effect, daily births should be lower on weekends than weekdays and should correlate with mean daily visitor numbers. Results showed that births for all 16 species were randomly distributed through the week, and there was no significant decline in births on weekends. We conclude that the ‘weekend effect’, if such a thing exists, does not appear to be a feature of zoo births, suggesting that elevated weekend visitor numbers are not sufficiently stressful to trigger delayed parturition.