Written by Sharon Smith MSc SEBC(Reg) IEng BHSAPC

The arrival of a healthy foal is a relief to all concerned, along with the realisation that events in the first year can have life-long consequences. Foals that are healthy, well socialised and correctly managed should become easy-to-handle, confident adults that are safer to be around. It’s human nature to seek improvement, and new ideas about how to deal with that first year have emerged – but is there any scientific evidence to support the claims?

Handling the foal within hours of birth is a suggested means of helping young horses deal with tack and humans in later in life. Called ‘Imprinting’ by the originators, it is a term used to describe an instant attraction to the first thing detected after hatching or birth. In reality, it takes 2 weeks for the foal to bond to the mare, and a few hours for the mare to bond with the foal [1]. The evidence suggests handling neonatal foals does not result in lasting behaviour benefits [2]. Imprinting attempts may even disrupt the mare bonding with her foal.

Alternatively, daily positive (gentle grooming, hand-feeding) contact with the mare is helpful to the foal. Only 15 minutes mare-handling a day in the first 2 weeks can improve her yearling’s reaction to handling, novel objects, and people [3]. Of course, the opposite may be true if the mare is stressed by the attention – however well intended. Also, in practice, once she has had a day or two with her foal we may start to habituate him to new people and experiences without risk of rejection, keeping sessions short and respecting the developing foal-mare bond.

New-borns should be given the opportunity to experience friendly horses at pasture as soon as possible. Feral mares choose to remain with other females to share the parenting duties. The foal becomes less concerned about his distance from his dam and find greater independence as they mature [4]. This can also work in domestic environments, if there is an established relationship between adults before the foal is born and there is sufficient space so that none feel crowded [5].

The new-born foal’s stomach wall is very thin and designed solely for milk in the first weeks. It is susceptible to infection and ulceration at a peak age of 2-3 months, before the immune system is fully developed [6]. But they also start nibbling at their dam’s feed from around 2 months of age. Equine Gastric Ulcer Syndrome (EGUS) is found in twice as many domestic foals (45%) as feral foals, before weaning. Grain-based feeds increase the risk. Also, in contrast to hay, foals eating alfalfa chaff were found to have increased incidence of ulcers in the deeper, glandular, part of the stomach [7]. The authors of this study suggested fibre length and coarseness of the alfalfa chaff mechanically damage the foal’s stomach lining. Steaming is a proven method for softening plant matter and should further soften hay for the foal’s delicate gut. 

After weaning, more than 90% domestic foals develop ulcers within two weeks. Domestic foals would usually be force-weaned at 6 months old (180 days) but earlier than 4 months is now not unusual [8]. It takes 4 months for the foal’s stomach walls to thicken up like a yearling’s. So, abrupt weaning prior to 4 months of age may hinder development in the stomach, which might have lifelong impacts [9]. Forced weaning is stressful at any age, increasing the risk of crib-biting and weaving [10] and development of EGUS [7, 11].

Feral foals may suckle for more than 12 months, if their dam allows it, but 9-10 months is more usual. We already know the mare’s milk aids development of mucous-producing cells, while the stomach is maturing [6]. From a traditional, clinical nutrition point of view, the quality of mare’s milk significantly declines after 3 or 4 months of lactation. Yet, ‘non-protein nitrogen’ (NPN) increases in milk up to at least 6 months [12]. NPN is known to beneficial to gut bacteria in ruminents, so perhaps occasional suckling beyond 6 months assists with stabilising/reinforcing a healthy hind-gut? Even if no such benefit is found, the other risks from forced weaning should be enough to make us reconsider the practice – especially with fillies. Trust the mare to do her job. If forced weaning is necessary, then leaving the foal in familiar surroundings with the immediate companionship of established companions, should provide some comfort when his mother is removed, and a grass and hay-based diet mediate against some effects of the resulting stress [10].

[1] Houpt, K. A. (2002). Formation and dissolution of the mare–foal bond. Applied Animal Behaviour Science, 78(2-4), 319-328.
[2] 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(1-2), 143-158.
[3] Henry, S., Hemery, D., Richard, M. A., & Hausberger, M. (2005). Human–mare relationships and behaviour of foals toward humans. Applied Animal Behaviour Science, 93(3-4), 341-362.
[4] Berger, J. (1986). Wild horses of the Great Basin: social competition and population size. University of Chicago Press.
[5] Kiley-Worthington, M. (1997). The behaviour of horses: in relation to management and training. JA Allen.
[6] Okai, K., Taharaguchi, S., Orita, Y., Yokota, H., & Taniyama, H. (2015). Comparative endoscopic evaluation of normal and ulcerated gastric mucosae in Thoroughbred foals. Journal of Veterinary Medical Science, 77(4), 449-453.
[7] Fedtke, A., Pfaff, M., Volquardsen, J., Venner, M., & Vervuert, I. (2015). Effects of feeding different roughage-based diets on gastric mucosa after weaning in warmblood foals. Pferdedheilkunde, 31, 596-602.
[8] Waters, A. J., Nicol, C. J., & French, N. P. (2002). Factors influencing the development of stereotypic and redirected behaviours in young horses: findings of a four year prospective epidemiological study. Equine veterinary journal, 34(6), 572-579.
[9] Metcalf, J. L., Song, S. J., Morton, J. T., Weiss, S., Seguin-Orlando, A., Joly, F., ... & Willerslev, E. (2017). Evaluating the impact of domestication and captivity on the horse gut microbiome. Scientific reports, 7(1), 15497.
[10] Nicol, C. J., Badnell-Waters, A. J., Bice, R., Kelland, A., Wilson, A. D., & Harris, P. A. (2005). The effects of diet and weaning method on the behaviour of young horses. Applied Animal Behaviour Science, 95(3-4), 205-221.
[11] Luthersson, N., Nielsen, K. H., Harris, P., & Parkin, T. D. H. (2009). Risk factors associated with equine gastric ulceration syndrome (EGUS) in 201 horses in Denmark. Equine veterinary journal, 41(7), 625-630.
[12] Doreau, M., & Boulot, S. (1989). Recent knowledge on mare milk production: a review. Livestock Production Science, 22(3-4), 213-235.