If you don't handle your long-haired piggies very regularly you may not notice there is a problem developing - you will see your pretty piggy walking around her pen looking like a very lovely long-haired piggy - not realising what may be lurking underneath - so, it is very important that you handle your piggy regularly and lift up the hair at the back end of your piggy and feel around their bottom to see if any knots / matts are developing - also, if each time you pick your piggy up she feels damp around her bottom end - {ruling out, of course a UTI} all the time, it could mean the hair is getting too long / knotted and is soaking up urine.