How do you reduce your horses health on Howrse?

Horses' health naturally declines after the age of 25 on Howrse. However, to speed it up, you could do a number of things:

-do not put your horse to sleep

-age your horse with minimum energy, ideally less than 5%

-do not feed your horse

-do not groom your horse

-do not put your horse in the box or meadow

Doing all these things, your horse's health would go down pretty fast. Hope that helped!