Imprint Training Part 3: Minimally Invasive Neonatal Interactions

Because of potential harm through the creation of states of flooding and learned helplessness in foals, imprint training represents a serious equine welfare issue and is not a recommended practice.  Hands-off methods, like gentle handling of the dam and exposure to a motionless person, are minimally invasive and more widely accepted from a welfare perspective.

Exposure to a motionless person

Experiments have been conducted to test whether consistent exposure to a motionless person will have any impact of the foal-human bond (Henry et al., 2006; Henry et al., 2007). In such experiments, the mare is normally tethered to the wall while a person stands motionless in the stall for a period of time, approximately 15 minutes, while the behaviour and spatial arrangements of both mare and foal in relation to each other and to the experimenter is recorded. The first session normally occurs within 12 to 20 hours of birth and is repeated for 5 days. In their experiments, Henry et al. (2006) did not notice any large differences between the group of foals exposed to a motionless person and the control group. Although, in cases where there was a higher degree of interest in the experimenter exhibited by the mare, there was a correlation of closer proximity of the foal to the handler, and they had a lower flight distance from an approaching human when compared to handled foals, suggesting that regular visual contact may be more beneficial than direct physical contact.

Gentle handling of dam

“In horses as in all mammals, the mother constitutes in an early postnatal period the main environment of her young which is dependent on her for sustenance, protection and behavioral stimulation” (Henry et al., 2007, p.515). The bond between a foal and its dam has an important role in the foal’s development, with the dam modelling behaviours in relation to the physical and social environments, including feeding preferences and reactions to humans (Henry, S., Hemery, D. Richard, M.A., & Hausberger, M., 2005). Multiple studies (see Henry et al., 2007) have demonstrated that direct postnatal handling of foals provides, if any, limited short-term advantages in the tractability and trainability of foals later in life. Gentle handling, brushing and hand-feeding of the dam, however, enhances the trainability of the foal, as it models a positive horse-human relationship.

Experiments conducted with neonatal foals (Henry et al., 2005) and 6-month old foals (Henry et al., 2007) produced similar results, exhibiting in both cases that “handling of foals is not necessary to improve their reactions to humans and that… the natural tendency of foals to learn from their dams is an effective way to establish positive relationships with naive foals” (Henry et al., 2007, p.518). In the study of neonatal foals, the beneficial effects were still evident at 1 year of age, as observed by the experimental foals’ receptivity to being approached and stroked by unfamiliar humans (Henry et al., 2005). In the experiments carried out with 6-month old foals (Henry et al., 2007) it was observed that the foals’ interest in the mares’ handler increased significantly over the 5 days of the process, exhibited by the foals directly engaging with the handler through “sniffing, nibbling and chewing” (p.516). In comparison to the foals in the control group, which appeared fearful of humans, the experimental foals were more willing to interact with the experimenter and accept human contact.

McGreevy (2012) suggests that when the handler is interacting with the dam, it is appropriate to gently and consistently interact with the foal too, as long as extra caution is taken to avoid inducing a flight response in the foal or disrupting the mare-foal bond. As long as these precautions are taken, “regular training activities that fully align with learning theory and, in particular, pressure release contingencies, can be learned at an early age” (p.87).

Recommendations

More research is needed to determine whether there is a critical learning period for foals and if there are any long-term benefits of imprint training on the tractability of horses. If, as McGreevy (2012) indicates, most of the recent literature suggests that foals appear to be in a state of distress and show strong signs of resistance to the process of imprint training, and given the inconsistent findings presented here, then perhaps the practice as advocated by Miller and the like should be, if not altogether discontinued, at the very least altered significantly.  If such procedures are to be beneficial, specific, minimally invasive, standardized processes should be established, guided by learning theory and developed with the highest degree of equine welfare in mind, for both foal and dam.

The most beneficial approach may be to eliminate all instances of neonatal handling and focus instead on the mare-human relationship, with the exception of any necessary medical interventions. What may be received as positive reinforcement in older horses, handling and stroking, is completely foreign to neonatal foals, and not a part of the equine ethogram (McGreevy, 2012). Therefore, handling at such an early stage is not necessarily a rewarding experience for foals. Regular, positive visual contact with humans and observation of the dam-human bond may be more beneficial to the foal than direct physical contact with a human. As demonstrated by studies done on the social modelling that occurs between the dam and foal, it is not necessary for humans to handle foals to improve tractability and trainability at later stages (Henry et al., 2006; Henry et al., 2007).

The most important activities within the first hours, days, and weeks of a foal’s life are those it engages in instinctually and learns from its dam. There is plenty of time to develop the foal-human bond. In the meantime, interacting with the dam and allowing for natural social, species-appropriate learning, whereby the foal can observe a positive dam-human relationship is the recommended approach.

References

Henry, S., Hemery, D., Richard, M.A., & Hausberger, M. (2005). “Human-mare relationships and behaviour of foals toward humans.” Applied Animal Behaviour Science, 93, p. 341-362.

Henry, S., Richard-Yris, M.A., & Hausberger, M. (2006). “Influence of Various Early Human-Foal Interferences on Subsequent Human-Foal Relationship.” Developmental Psychobiology, 48, p. 712-718.

Henry, S., Briefer, S., Richard-Yris, M.A., & Hausberger, M. (2007). “Are 6-Month-Old Foals Sensitive to a Dam’s Influence?” Developmental Psychobiology, 49, p. 514-521.

Lansade, L. Bertrand, M., Bouissou, M.F. (2005). “Effects of neonatal handling on subsequent manageability, reactivity and learning ability of foals.” Applied Animal Behaviour Science, 92, p. 143-158.

McGreevy, P. (2012). Equine Behaviour: A Guide for Veterinarians and Equine Scientists, 2nd ed. Edinburgh: Elsevier.

Simpson, B.S. (2002). “Neonatal Foal Handling.” Applied Animal Behaviour Science, 78, p. 303-317.

Imprint Training Part 2: Less Invasive Approaches

While Miller’s methods are extreme, there are less invasive variations of imprint training, which omit the insertion of fingers into the ears, nostrils, and anus, with interactions spaced out over a longer period of time. In one example, the foal receives gentle patting on the head, shoulders, back, hindquarters and legs, and lifting of the feet. Unlike in Miller’s method, the foal is not rubbed with a plastic bag; rather, a plastic bag is shaken in front of its head. In the second session, the foal is fitted with a halter, and in the seventh, it is led 40 meters. Somewhere in between the second and fourth session, the foal is conditioned to move forward or backward in response to pressure applied to its hindquarters or chest (Lansade et al., 2005).

In her neonatal handling experiments with 15 foals (7 handled, 8 controls) Barbara Simpson (2002) observed that “[p]robing the ears, inserting a finger up the nose, tapping the feet, or inserting a gloved, lubricated finger into the anus of neonatal foals did not make them less reactive to inserting a nasogastric tube [or] tapping the feet with a [farrier’s] hammer, or inserting an enema probe (to simulate a thermometer)” nor were the handled foals any more accepting of the haltering procedure than the control foals (p.315). However, Simpson indicates that when tested at 4 months of age the handled foals were more likely to approach individuals, appearing calmer and friendlier than the control foals, and they had lower heart rate responses when presented with some stimuli.

Assisted Suckling

Assisted suckling is a neonatal handling process that warrants a closer look. A routine procedure at breeding farms, assisted suckling begins with a foal being restrained and led to the mare’s teat approximately 30 minutes following birth. The teat is placed into the foal’s mouth, and the foal is held by the body and head for the duration of the first bout of suckling (up to 30 minutes) and then left alone with the mare (Henry et al., 2006).

References

Henry, S., Richard-Yris, M.A., & Hausberger, M. (2006). “Influence of Various Early Human-Foal Interferences on Subsequent Human-Foal Relationship.” Developmental Psychobiology, 48, p. 712-718.

Lansade, L. Bertrand, M., Bouissou, M.F. (2005). “Effects of neonatal handling on subsequent manageability, reactivity and learning ability of foals.” Applied Animal Behaviour Science, 92, p. 143-158.

Simpson, B.S. (2002). “Neonatal Foal Handling.” Applied Animal Behaviour Science, 78, p. 303-317.

Imprint Training Part 1: Perceived Benefits & Welfare Issues 

Imprinting refers to the process by which a young animal establishes a primary social bond with another animal (usually its mother) shortly after birth, from whom it will receive information about its environment and learn specific behaviours at critical periods of time and stages of development (Williams et al., 2003; Henry, Briefer, Richard-Yris, & Hausberger, 2007). The individual that the animal bonds to is one which regularly provides it with pleasure and comfort, thereby stimulating the production of endorphins and reinforcing the bond through an addiction-like process, a learning process that is not yet entirely understood. This process also applies to objects. Therefore, both unfamiliar individuals and unfamiliar objects may initially induce a fear response in the young animal. However, this can be overcome with sufficient exposure (Hoffman, 1996).

Imprint training in foals describes a process of forceful neonatal handling and exposure to aversive stimuli, which is often quite invasive and occurs almost immediately after birth. Proponents believe that such processes will condition a horse to be less reactive, more manageable, easier to handle and train, and result in a stronger horse-human bond (Henry, Richard-Yris, & Hausberger, 2006; McGreevy, 2012; Spier, Berger Pusterla, Villarroel & Pusterla, 2004; Williams et al., 2003). While there is some evidence that imprint training in foals is effective in the short-term, there is a lot of conflicting evidence about its long-term effectiveness and suitability as a training methodology (Lansade, Bertrand & Bouissou, 2005; Simpson, 2002).

Given the diversity of approaches to the process, it is no wonder results are inconclusive. The ideal time to start imprint training as suggested by 7 different authors ranges from birth or 10 minutes following birth to 14 days of age, with repetitions of the process and testing for results occurring at wildly varying frequencies (McGreevy, 2012). Furthermore, a critical learning period in foals has not yet been established, and despite Robert Miller’s claims, foals will not “imprint on” (establish a social preference for) a human over its dam (Lansade et al, 2005; Spier et al. 2004; Williams et al., 2003).

Miller’s Method

Imprint training, as espoused by veterinarian Robert Miller, advocates for the handling of the foal immediately following birth and continuing in a series of sessions occurring over a 48 hour period. The goal is to desensitize and habituate the foal to human contact with the belief that it is safer than training a larger, stronger and potentially dangerous youngster, and that such contact will have a long-lasting impact, making it easier to handle the foal when the time comes for more advanced training and routine veterinary procedures (McGreevy, 2012).

When following Miller’s program, the handler will physically separate the foal from the dam within 10 minutes of birth and restrain it to dry its body and cut the umbilical cord. The next step involves holding the foal before it stands, until it ceases to resist, and then rubbing the entire body until the foal shows relaxation, including the ears (inside and out), eyes, lips, tongue, face, neck, thorax, sides, stomach, rump, tail, perineum and external genitalia, lifting and handling each foot, and lifting and moving the tail up and down and from side to side (McGreevy, 2012; Spier et al., 2004; Williams et al. 2003).

Once the foal ceases to resist the handler’s touch, a number of aversive stimuli are introduced until signs of panic subside, such as clippers, a simulation of an anal exam, including insertion of a rectal thermometer, rubbing the foal’s entire body with a plastic bag, and spraying the foal with water from poll to tail. A number of unusual sounds and aversive visual stimuli are also presented, such as whistles, gunfire, loud music, waving flags and swinging ropes (McGreevy, 2012).

The handler then proceeds to apply pressure to the girth region by placing his or her arms around the foal and “compressing rhythmically until any resistance abates” (McGreevy, 2012, p.85). A halter is placed on the foal and the handler then attempts to lead it and teach it to stand still by holding it in place until it stops struggling. The handler may also push the foal from either side until it moves away in response to pressure (Williams et al. 2003). The initial imprinting session lasts for 45 to 60 minutes and the entire procedure is repeated when the foal is 24 hours old (Spier, et al., 2004).

Perceived benefits of imprint training

Studies conducted by Miller, Mal and McCall, and Simpson (see Lansade et al., 2005) all indicate that foals subjected to imprint training are more tractable and less reactive to stimuli to which they were introduced as neonates than non-handled foals.  Experiments conducted by Simpson (2002) support these claims. She found significant differences in the calmness and perceived friendliness of handled foals, i.e. willingness to approach humans in the test paddock, and lower heart rates in comparison to the control foals when presented with stimuli when tested 4 months after the initial sessions.  Whereas Lansade et al. (2005) state that handling from birth may be advantageous because “very young foals are weaker, have fewer defensive reactions and may be less fearful of humans than older foals,” however, they go on to say that “the effects of handling are only temporary” and that “the handling procedure needs to be repeated regularly until the horse is broken in” (p.156).

Welfare issues

Despite the perceived benefits, the decision to engage in any neonatal handling procedure should be approached with caution. Handling a foal at birth does not fit within the equine ethogram (the catalogue of horse-specific behaviours) (McGreevy, 2012) and there is a risk that over-handling of the foal will interfere with the mare-foal bond (Simpson, 2002). Also of importance is the fact that the young of highly precocial species, such as horses, receive “little physical contact, apart from the very early licking at birth and later direct social interactions” with the dam, the frequency of which is low (Henry et al., 2007, p.712-713) especially when compared to the 30 to 50 interactions that Miller prescribes for imprint training. Miller’s techniques may, in fact, equate to a process of flooding, which leaves the foal in a state of learned helplessness rather than achieving true habituation or desensitization (McGreevy, 2012).

Many horses do not receive training until later in life and are still able to learn the skills and behaviours that are taught during imprint training, such as leading and acceptance of clippers (Williams et al., 2003).

It has been observed that even foals that have received imprint training are as difficult to approach as controls if they don’t receive regular handling after the initial sessions. Also, there has been little proof that acceptance of aversive stimuli is accomplished through imprint training, nor are reactions to isolation from conspecifics or learning abilities noticeably improved (Lansade et al., 2005; McGreevy, 2012).

References

Henry, S., Richard-Yris, M.A., & Hausberger, M. (2006). “Influence of Various Early Human-Foal Interferences on Subsequent Human-Foal Relationship.” Developmental Psychobiology, 48, p. 712-718.

Henry, S., Briefer, S., Richard-Yris, M.A., & Hausberger, M. (2007). “Are 6-Month-Old Foals Sensitive to a Dam’s Influence?” Developmental Psychobiology, 49, p. 514-521.

Hoffman, H.S. (1996). “Imprinting: A brief description.” Retrieved from http://www.animatedsoftware.com/family/howardsh/imprint.htm

Lansade, L. Bertrand, M., Bouissou, M.F. (2005). “Effects of neonatal handling on subsequent manageability, reactivity and learning ability of foals.” Applied Animal Behaviour Science, 92, p. 143-158.

McGreevy, P. (2012). Equine Behaviour: A Guide for Veterinarians and Equine Scientists, 2nd ed. Edinburgh: Elsevier.

Simpson, B.S. (2002). “Neonatal Foal Handling.” Applied Animal Behaviour Science, 78, p. 303-317.

Spier, S.J., Burger Puterla, J., Villarroel, A. & Pusterla, N. (2004). “Outcome of tactile conditioning of neonates, or ‘imprint training’ on selected handling measures in foals”. The Veterinary Journal, 168, p. 252-258.

Williams, J.L., Friend, T.H., Collins, M.N., Toscano, M.J., Sisto-Burt, A. & Nevill, C.H. (2003). “Effects of imprint training procedure at birth on the reactions of foals at age six months.” Equine Veterinary Journal, 35 (2), p. 127-132.