Locomotor Inhibition in Adult Horses Faced to Stressors: A Single Postpartum Experience May be Enough!

Abstract

Despite the number of postpartum handling that a newborn experiences, few studies focus on their long-term consequences. In rats, regular long separations from the mother, during the early life, led to modifications of the locomotor activity when the animal is confronted to a stressor. In horses, one component of the behavioral response to stressful situation is active locomotion. We wondered if the routine postpartum handling undergone by foals, would affect their level of reactivity or the way they express their stress, when older. One single prolonged bout of handling just after birth clearly affected later adult expression of stress reactivity. In social separation associated with novelty, handled, and unhandled horses produced an equal amount of whinnies, showing a similar vocal response to stress. However, both groups differed in their locomotor response to the situations. Early handled foals expressed less of the active forms of locomotion than the control group. Our findings highlight the need of further reflections on long-term effects of routine handlings procedures close to birth.

The human newborn’s umwelt: Unexplored pathways and perspectives

“…Several studies underline the impact of the first neonatal interactions/handling procedures on behavioral development (horses: Hausberger, Henry, Larose, & Richard-Yris, 2007;rodents: Lehmann & Feldon, 2000;Pryce et al, 2005). The routine procedure involving intensive tactile stimulations of horses just after birth induces long term disturbances and locomotor inhibition (Durier, Henry, Sankey, Sizun, & Hausberger, 2012;Henry, Richard-Yris, Tordjman, & Hausberger, 2009). Similarly, early postpartum routine practices could affect human newborns' sensory and emotional development.…”

An unexpected acoustic indicator of positive emotions in horses

“…[ 36 ]). Several studies already showed that some of their vocalizations were enhanced in specific situations according to the valence associated [ 37 , 38 ]. Moreover, particular acoustic parameters of the whinnies have been proposed to encode either the level of arousal or the valence of emotions (e.g.…”

Unexpected behavioural consequences of preterm newborns' clothing

“…The postures of NB in sleepwear suggest that constraints related to this type of clothing may be stressful because it hinders movements, potentially creating a state where a baby learns that his/her attempts to move are unsuccessful (see also foals 10 ), but even more it prevents soothing self-contact with his/her head. Reports suggest that physical restrictions of animals (foals) at an early stage could induce long term alterations of their emotional expression 10 37 . Although our study did not evaluate long term effects, it constitutes a solid basis for stimulating innovative research in this important field.…”

“…The inability to “escape” from a situation through movement may induce increased immobility and even enhance helplessness in the long term 8 9 . For instance, horses that underwent a short neonatal handling procedure preventing movement showed, when exposed to novelty, locomotor inhibition rather than heightened mobility 10 . The amount of stressors perceived by very young preterm infants (assessed by Neonatal Infant Stressor Scale) also has an effect on their motor development (assessed by NICU Network Neurobehavioral Scale) 11 .…”