Aside from the obvious physical aspects of too much condition
affecting movement, respiratory stress, joints etc, the biggest issue on
the horses physiology is the on set of metabolic problems from excess
blood glucose and insulin: such as insulin resistance, laminitis,
endocrine complications such as Cushing’s disease or Equine
Metabolic Syndrome (EMS). The link between all of these is obesity,
which is why it is vital to recognise the onset of too much condition and deal with it quickly.

Excess fat in a horse is seen in a crested neck and fat pads on the body.