According to new research into domestic horses by a team in France, staying with mum fundamentally changes the developing brain and body of foals.
Much is known about the negative impact of losing a parent early or having bad care in both animals and humans, but less is known about how positive social time shapes an individual’s future.
So researchers at INRAE (National Research Institute for Agriculture, Food and Environment) in France followed two groups of foals to see how staying with their mothers changed how they grew up, publishing their findings in Nature Communications.
One group was separated from their mothers at six months, which is standard practice on many horse farms, and the other group stayed with their mothers until they were more than a year old. This is typically what happens with mares and their foals in the wild.
To understand what was happening to the animals, the scientists used MRI scans to look at their brains, took blood tests to check their health, and observed their behaviour. They also performed a social network analysis, which was a way of seeing which other horses they were friendly with and how they fit into the herd.
The results showed that foals that stayed with their mothers were much better off in several areas. Their brains developed faster in parts that control emotions and social behaviour, and there was stronger connectivity in the default mode network. In humans, this brain network is important for social cognition.
These young horses were also more exploratory than foals that spent less time with their mothers and were easier to train. One of the most surprising findings was that they gained more weight even though they spent less time eating. The researchers attribute this to better energy efficiency. Because the horses felt safe, they did not have to waste fuel on being stressed.
“Our findings underscore the essential role of prolonged maternal presence in fostering the successful development of social competences and suggest that affiliative behaviours [friendly, social interactions that reinforce bonds] are involved in the establishment of foundational networks involved in social development across social mammalian species,” wrote the scientists.
Ultimately, this study highlights the benefits of keeping young offspring with their mothers for longer, which could help us improve animal welfare and behaviour.
