The cause of 'pica' disease is

The cause of 'pica' disease is Phosphorus deficiency.
It is important to note that pica often occurs in herds that are thriving & healthy. Low dietary fibre in the cow's diet, due to the rapidly growing grass during the breeding season can also cause pica.
Symptoms of pica in cattle are eating & licking stones off roadways, Chewing water piping, cubicle mats, eating electric fence handles or Drinking or licking urine.