Signs include a stiff, reluctant gait, sweating, muscle tremors and dark urine during or after work. Stop exercise at once, keep the horse warm and still, and call your vet. Prevent it with steady conditioning and diet management.
What happens
In tying up, the large muscles of the hindquarters and back cramp painfully and can be damaged, releasing pigment that turns the urine dark. It ranges from mild stiffness to a horse that cannot move, and severe cases can harm the kidneys.
Spot the signs
Watch for a sudden reluctance to move, a stiff, short, pottery gait, hard and painful hindquarter muscles, sweating, a raised heart rate and dark, coffee-coloured urine. Signs usually appear during or shortly after exercise.
What to do
Stop work immediately, do not walk the horse on, and keep it warm and calm where it stands. Offer water. Call your vet, since severe cases need treatment and forcing a tied-up horse to move can worsen muscle damage.
Common triggers
Tying up is often linked to too much rest followed by hard work, a high-starch diet relative to the workload, electrolyte imbalance, and in some horses an inherited muscle disorder. Cold, wet weather and stress can play a part too.
How to prevent it
Build fitness gradually, keep exercise consistent rather than hard days after rest, warm up and cool down properly, and match feed to the work, favouring forage and fibre over excess starch. Replace salts lost in sweat with electrolytes, and support the diet with a balanced supplement. Prone horses need a plan from your vet.
