Some horses, particularly obese horses, have a propensity to have recurring founder during the periods of lush grass growth. Usually these are cool season grasses that grow actively during the spring and fall. As the grass grows rapidly the horse's gait gets short and choppy and they begin to spend more time laying down on the ground. Recent research has led us to a better understanding of this problem. This article concerns the diagnosis, causes, treatment, and prevention of this common problem. Note, this is a companion article to Overview of Founder which contains important information concerning founder.

The signs will appear during periods of rapid pasture growth during the cool seasons of the year. Obese horses are most prone to the problem but also older horses and horses with previous bouts of founder may be effected. First noticed is a shortening of his stride that as time goes on the horse appears stiff with a careful, pottery walk. The stride will be much worse on the pavement than the grass. As time goes on, the horse will spend increasing times lying on the ground.

During the early stages, with no past history, the diagnosis may not be readily apparent: one foot may be worse than the other, mimicking a bruise. The pulse and heat may not be that marked in mild cases and hoof tester responses may also be equivocal causing easy confusion with the onset of navicular syndrome. An important clue will be careful examination at the trot on lunge going both directions. The lameness will be found to switch, with the inside foot always being the lame one. Trot the horse over a surface that goes from soft to hard: does the horse worsen significantly as he moves onto the hard surface. Another clue to watch for is, after holding up the lamest foot for a minute or two and then setting it down, the horse with mild founder will pick up the opposite foot as though painful for a few seconds. Presumably bearing all the weight on one fore foot exacerbates the pain.