Natalie Waran

How reliable is temperament assessment in the domestic horse (Equus caballus)

Abstract Differences in behavioural characteristics between individuals of the same species are often described as being due to the temperament of the individuals. These differences can have enormous implications for welfare with some individuals apparently being able to adapt to environmental challenge more easily than others. Such differences have resulted in animals often being described as either ‘active’ copers, which try to escape from or remove an aversive stimulus, or ‘passive’ copers, which show no outward signs of a situation being aversive, thus, appearing to be unaffected. Tests previously developed to assess the temperament of animals have been criticised for several reasons. Behaviour is often recorded and categorised using methods that are not objective and tests are generally carried out once with no consideration of whether or not behavioural responses are consistent over time. This study takes these factors into account. The behaviour of 33 horses was recorded in three types of test—an arena test, response to a person and response to an object. In order to test whether or not responses were consistent over time, the tests were repeated three times with an average of 9 days between trials. Test results were validated using responses from questionnaires completed by the farm team leader. The data were analysed using an initial principal component analysis (PCA) and factor analysis. The horses were found to behave consistently over the three trials in their responses in the arena test. The responses to the person test and the object test were similar to each other; however, these responses were not consistent over trials. The behaviour in the arena test was unable to be used to make a prediction of behaviour in the person and object tests and vice versa. The responses shown by the horses did not enable them to be categorised as either active or passive copers. Behavioural responses in the tests were not predictive of the response to a startle test (water spray), nor could they be used to predict status or response to being reintroduced to the group after testing. There was no relationship between the responses in the tests and the ratings given by the farm team leader. It was concluded that horses vary widely in their responses to artificial behavioural tests, with only the responses to an open-field arena test being consistent over time, and therefore, the only type of test which can indicate some core factor of temperament.

Neuropathic changes in equine laminitis pain

Abstract Laminitis is a common debilitating disease in horses that involves painful disruption of the lamellar dermo‐epidermal junction within the hoof. This condition is often refractory to conventional anti‐inflammatory analgesia and results in unremitting pain, which in severe cases requires euthanasia. The mechanisms underlying pain in laminitis were investigated using quantification of behavioural pain indicators in conjunction with histological studies of peripheral nerves innervating the hoof. Laminitic horses displayed consistently altered or abnormal behaviours such as increased forelimb lifting and an increased proportion of time spent at the back of the box compared to normal horses. Electron micrographic analysis of the digital nerve of laminitic horses showed peripheral nerve morphology to be abnormal, as well as having reduced numbers of unmyelinated (43.2%) and myelinated fibers (34.6%) compared to normal horses. Sensory nerve cell bodies innervating the hoof, in cervical, C8 dorsal root ganglia (DRG), showed an upregulated expression of the neuronal injury marker, activating transcription factor‐3 (ATF3) in both large NF‐200‐immunopositive neurons and small neurons that were either peripherin‐ or IB4‐positive. A significantly increased expression of neuropeptide Y (NPY) was also observed in myelinated afferent neurons. These changes are similar to those reported in other neuropathic pain states and were not observed in the C4 DRG of laminitic horses, which is not associated with innervation of the forelimb. This study provides novel evidence for a neuropathic component to the chronic pain state associated with equine laminitis, indicating that anti‐neuropathic analgesic treatment may well have a role in the management of this condition.

Pilot epidemiological study of attitudes towards pain in horses

This preliminary study investigated the attitudes, and evaluated the current practice of a sample of the veterinary profession in the UK in relation to the management of pain in horses. In June 2001, a questionnaire was posted to 260 veterinarians in specialised equine practice, and 140 veterinarians in general practice with a significant equine caseload. There was a 25 per cent response rate to the questionnaire, which recorded information about the availability and prescription of analgesic drugs, the factors influencing the selection of analgesics and their administration, and estimates of the severity of pain associated with selected clinical conditions. There were considerable variations in the practices applied to manage pain in horses, implying that there are similar attitudinal barriers to the optimal management of pain in horses as have been identified in other domestic species.

Behavioural and physiological responses of pigs to sound

Abstract Sound is a potential stressor to pigs throughout their lives. The following two studies examined the behavioural and physiological responses of pigs to both artificial and real sound. In the first study, piglets (n = 8) were exposed to artificially generated sounds, nominal intensities of 85 or 97 dB(Lin), and frequencies of 500 Hz and 8000 Hz for 15 min, during an hour experimental session. In the second study the piglets (n = 8) were exposed to 20 min of four sounds: farm recording, Leq 80 dB(Lin); transport recording, Leq 83 dB(Lin); abattoir recording, Leq 84 dB(Lin) and white noise, Leq 89 dB(Lin). In both studies piglets were exposed to the sounds in an arena to which they had previously become accustomed and a companion pig was present in the experimental room. The behaviour and heart rate of the piglets were recorded pre-, during and post-exposure to all the sounds in both studies. In addition observations were also made in a control session with no sound stimuli. In both studies an increase in heart rate (maximum 20 beats min−1) was observed for the first 15 min of exposure to sound (P

Is there evidence of learned helplessness in horses

Learned helplessness is a psychological condition whereby individuals learn that they have no control over unpleasant or harmful conditions, that their actions are futile, and that they are helpless. In a series of experiments in which dogs were exposed to inescapable shocks, this lack of control subsequently interfered with the ability to learn an avoidance task. There is evidence that both neural adaptations and behavioral despair occur in response to uncontrollable aversive experiences in rodents, although this has yet to be demonstrated in other species such as horses. However, certain traditional methods of horse training and some behavioral modification techniques—it has been suggested—may involve aversive conditions over which the horse has little or no control. When training and management procedures are repeatedly unpleasant for the horse and there is no clear association between behavior and outcome, this is likely to interfere with learning and performance—in addition to compromising welfare. This article reviews published literature and anecdotal evidence to explore the possibility that the phenomenon, learned helplessness, occurs in the horse.

Effects of loading and transport on the heart rate and behaviour of horses

Abstract Although there is much anecdotal evidence to suggest that some horses are stressed during transport, very few empirical studies have been done that describe and quantify the responses of horses to transport. The aim of this preliminary study was to describe the behaviour and heart rates of horses during loading and transport that would enable further studies to be carried out on the effects of different journey lengths and management procedures. Therefore, the behaviour and heart rates of horses were measured during loading, confinement in a stationary vehicle and transport for 25 min. In the first study the behaviour and heart rates of 32 horses of various ages ranging from yearlings to over 3 years, were compared during loading. Evasive behaviour during loading was only observed in very young horses, and the time the yearlings took to load (368 s) was much greater ( P P −1 higher ( P

Sound avoidance by domestic pigs depends upon characteristics of the signal

Habituation to novel, loud and predictable sound stimuli appears to occur in pigs, though this has not been unequivocally demonstrated. In addition, different types of sound may be more or less aversive; humans find unpredictable, intermittent sound more aversive than constant sound. The aim of this study was to test these two hypothesis in pigs. Two groups of 12 pigs, weighing 25 kg, were individually exposed to a test sound in a modified unsignalled one-way avoidance procedure. The test sound for the first group was a recording from an animal transporter played at 84 dB(Lin), with a rise time of 2 s (uniform, U). For the second group, silent fragments, 59 dB(Lin), were randomly inserted into the recording, played at 86 dB(Lin), and the rise time was changed to <0.1 s (Intermittent, I). A total of 40 consecutive, 5 min tests were carried out for each pig, 20 control and 20 with sound present. Sound present tests were arbitrarily split into three groups, comprised of tests 1–6, 7–12 and 13–20, for analysis. Pigs did not significantly avoid the uniform sound in any of the groups of tests, though they did increase their performance of active behaviour when the sound was first introduced (Control test no. 20, 15% of behaviour scans; Sound test no. 1, 37% of behaviour scans; p<0.01). The intermittent sound was significantly avoided during all three sets of sound tests (Mean percentage of time spent avoiding sound area: Control tests 2–20, 35%; Sound tests 1–6, 67%; Sound tests 7–12, 73%; Sound tests 13–20, 66%, p<0.05). These pigs also showed significant increases in active behaviour during the first sound test (Control test no. 20, 14% of behaviour scans; Sound test no. 1, 42% of behaviour scans; p<0.01). The results suggest that aversion is dependent on characteristics of the sound, such as uniformity, rather than neophobia.

Training methods and horse welfare.

Many aspects of horse care and handling are based upon convenience and traditional practices. Many of these methods of management and practice do not take into account the natural behaviour of horses. This is despite the belief that although domestic horses are probably more docile, stronger, faster growing and faster moving than their ancestors, they are unlikely to have lost any natural behaviours. The performance or sport horse is expected to perform a wide variety of movements and tasks, some of which are unnatural or exaggerated and most of which must be learned. The term ‘training’ is commonly used to describe the processes whereby the human handler introduces the horse to new situations and associations. Performance horses are often required to tolerate stimuli that are innately aversive or threatening, such as having a person on their backs. They are also trained to respond to a stimulus with often unnatural or over-emphasised behaviour, such as some of the dressage movements. Effective and humane training requires an understanding of the processes underlying behaviour. These include knowledge of behaviour under natural conditions, learning processes, the influence of early experience and motivational forces. Horses differ from the other main companion animal species, namely cats and dogs, in that they are a prey species. They most commonly flee from dangerous and painful situations. Horses readily learn to avoid potentially threatening situations and if their attempts to avoid associated stimuli are prevented, they will often exhibit problem behaviours. In this chapter the history of horse training, the application of learning theory and a knowledge of equine behaviour to training, and innovative training methods are all considered.

The behavioural, endocrine and leucocyte response of ewes to repeated removal of lambs before the age of natural weaning

Abstract Changes in the blood leucocyte population in response to psychological stressors could increase susceptibility to disease and be useful in the assessment of animal welfare. This paper examines the effect of repeated lamb removal on the blood leucocyte population of ewes and quantifies the behavioural and endocrine responses to the stressor. Twelve ewes which had given birth to twins, were placed in separate pens with their lambs. After 13 days, the lambs (14–19 days old) from one group of six ewes (treatment group) were removed from the pens and placed in a pen 11 m from the nearest ewe. After 3 h the lambs were moved back to their dam. The lambs then remained with their dam for 3 h before being removed for a second period of 3 h. This procedure was repeated for 23 days. A control group of six ewes remained with their lambs continuously for the 24-day experimental period. The removal of lambs produced behavioural changes in the ewes. These included: orientation towards the lamb, vocalization, raised head, erect ears, and decreased lying and sleeping behaviours. Although these changes were present over the 24-day experimental period, there were signs of habituation after 3 days of the treatment. The endocrine responses to lamb removal were less marked. Some ewes showed a plasma cortisol and β-endorphin response on Day 1 of lamb removal, but the mean responses were not statistically different from the control group. There was no obvious plasma prolactin response to the treatment. On Day 10 of lamb removal, the blood concentration of neutrophils in the treatment ewes had increased and the proportion of CD2 lymphocytes and T19 lymphocytes had decreased compared with that of control ewes. There were no significant differences between the treatment and control ewes in either the delayed type hypersensitivity skin responses to Dinitroflurobenzene or the humoral antibody responses to ovalbumin. These results indicate that ewes can show behavioural responses to a stressor, such as repeated lamb removal. However, this stressor had no significant effect on the endocrine and immune measurements studied.

Recovery from transport and acclimatisation of competition horses in a hot humid environment.

The aims of the present field-based study were to investigate changes in fit horses undergoing acclimatisation to a hot humid environment and to provide data on which to base recommendations for safe transport and acclimatisation. Six horses (age 7-12 years) were flown from Europe to Atlanta and underwent a 16 day period of acclimatisation. Exercise conditions during acclimatisation (wet bulb globe temperature index 27.6+/-0.0 [mean +/- s.e.]) were more thermally stressful compared with the European climate from which the horses had come (22.0+/-1.8, P<0.001). Following the flight, weight loss was 4.1+/-0.8% bodyweight and took around 7 days to recover. Water intake during the day was significantly increased (P<0.05) compared with night during acclimatisation. Daily mean exercise duration was 72+/-12 min and the majority of work was performed with a heart rate below 120 beats/min. Respiratory rate (fR) was increased (P<0.05) throughout acclimatisation compared with in Europe, but resting morning (AM) and evening (PM) rectal temperature (TREC), heart rate (fC) and plasma volume were unchanged. White blood cell (WBC) count was significantly increased at AM compared with in Europe on Days 4 and 10 of acclimatisation (P<0.01), but was not different by Day 16. In conclusion, horses exposed to hot humid environmental conditions without prior acclimatisation are able to accommodate these stresses and, with appropriate management, remain fit and clinically healthy, without significant risk of heat illness or heat-related disorders, provided they are allowed sufficient time to recover from transport, acclimatisation is undertaken gradually and they are monitored appropriately.