03/30/2026
ARE WE WEANING FOALS TOO EARLY?
From the horses and problems I see, I know the answer is yes. Now an interesting new study suggests that how we manage the mare–foal relationship doesn’t just affect the foal in the short term, but can shape how they think, cope, and behave as adults.
Researchers compared foals weaned at around 6 months with those who remained with their mothers for longer, looking at brain development, behaviour, learning ability, and physiological stress markers.
Foals who stayed with their mothers:
• Showed differences in brain regions involved in emotional regulation and decision-making
• Had stronger connectivity in brain networks linked to processing information and responding appropriately to the environment
• Were more exploratory, more social, and quicker to approach novelty
• Learned handling tasks in fewer sessions and showed less resistance
• Despite spending less time feeding, foals with their mothers gained more weight
Whereas early-weaned foals:
• Showed higher cortisol levels, indicating greater stress
The concept at the centre of this research is allostasis – the brain’s ability to predict what is likely to happen and adjust behaviour and physiology in advance, based on past experience and current information.
Allostasis isn’t something a horse is born with. It develops through experience and from social learning. The mare appears to play a key role in this process, providing the foal with the information needed to interpret situations accurately. Without that early guidance, the developing horse may be more prone to overreact, misinterpret stimuli, or struggle to regulate stress.
We should be rethinking whether foals are being left with their dams for long enough. I very often see horses with behaviour problems who were weaned at 6 months or earlier (sometimes as young as 3 months), rather than the 8–12 months or longer they would remain with their dam naturally. The difference between foals who have had a more secure early upbringing and those weaned early is often striking in their behaviour, confidence, and ability to cope with the world around them.
The weaning process should not be treated as a management event driven by commercial timelines or the urgency to sell the foal. It is about how early life experience shapes the adult horse.
If behaviour, learning, and stress resilience are being influenced this early, what are the long-term consequences of how we currently raise and manage foals?
Study: Valenchon et al, Affiliative behaviours regulate allostasis development and shape biobehavioural trajectories in horses, 2026, Nature Communications
