What happened if a slave attempted to escape?

Slave return awards would be put around. 
There would be people who made a living hunting for escapee slaves.
And, when they were returned(if ever), slaves were tortured but not enough that they couldn't work.

True blindness may be caused by trauma to the eye, severe conjunctivitis due to  ibr (infectious bovine rhinoceros) or pink eye or other infections, leptospirosis, lead poisoning, selenium toxicity, fungal infections, vitamin a  deficiencies, rabies, vitamin b12 deficiency, neoplastic of the orbit or  conjunctiva, cataracts, congenital malformations, etc.