daniel weness reported on tuesday that a storage canister with vials of bull semen had been taken from his farm .
the $ 500 canister held vials worth between $ 300 and $ 1,500 each .
theft happened between april 1 and 7 , and weness was away on easter .
there is a market for bull semen because it helps farmers on transportation costs of putting a bull and a cow in the same pen to breed .