Are fish from a cow pond edible?

My ‘new’ old pond had been used by cows for the last 7-10 years prior to me buying the property. They have been no cows since September and I was surprised to find a high population of small bass. In the spring I plan on having a troop of Scouts help thin them out. Will the fish be OK for a fish fry or should I use them as fertilizer?

Is it possible to get fish tested and if so what should they be tested for?