Autumn has arrived. I hear it whispering in the leaves, and feel it in the fluffy coat of the yearling

Autumn can bring noticeable changes in horses’ behaviour, energy levels and comfort. As daylight shortens, horses undergo seasonal physiological changes, including changes in coat growth, metabolism, reproductive cycling and endocrine activity.

One important autumn change is the natural seasonal rise in ACTH, a hormone produced by the pituitary gland. This rise is especially relevant in older horses and those with pituitary pars intermedia dysfunction, or PPID also known as Cushing's disease. Autumn is also a recognised risk period for laminitis, particularly in horses and ponies with insulin dysregulation, equine metabolic syndrome or PPID. Grass should not be assumed to be “safe” simply because summer has passed. Autumn pasture may still contain enough non-structural carbohydrate to trigger problematic insulin responses in susceptible horses. For this reason, new foot soreness, pottery movement, reluctance to turn, increased lying down, heat in the feet or a stronger digital pulse should be treated seriously and discussed promptly with a vet.

Some horses may appear more irritable, reluctant or “grumpy” in autumn, but this should not automatically be blamed on hormones or the weather. Behavioural change is often one of the earliest signs of discomfort. Pain from low-grade laminitis, musculoskeletal strain, gastric discomfort, saddle or tack fit, dental issues, social stress, reduced turnout, changes in routine or increased stabling should all be considered. A horse that is newly resentful to groom, tack up, catch, ride or handle should be assessed for pain.

Mares may also behave differently as day length decreases. Horses are seasonal breeders, and many mares pass through an autumn transition before entering winter anoestrus, when reproductive cycling becomes reduced or absent. During this transitional period, some mares may show irregular or less predictable oestrous behaviour before settling into their winter pattern.

It is also normal for some horses to become a little less active as winter approaches. Research shows that horses and ponies can reduce activity and metabolic rate as part of seasonal energy conservation. However, sudden, marked or progressive lethargy is not something to dismiss as “just autumn”, especially in older horses or those at risk of PPID, insulin dysregulation, laminitis, pain or systemic illness. In these cases, veterinary advice is recommended.

Overall, autumn changes are normal, but they can also reveal underlying health problems. The safest approach is to monitor behaviour, body condition, feet, movement, appetite, coat change and energy levels closely. Any new irritability, reluctance, lameness, foot sensitivity or unusual tiredness should be investigated early, because prompt recognition of pain or endocrine disease can make a significant difference to welfare and long-term soundness.

Bibliography

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