Police say they have a suspect and a motive in the theft of 49 cows from a farm in Dartmouth.  Police Chief Timothy Lee says the suspect and victim were well-known to each other and the theft had something to do with money. The owner of the cows is identified as Ahmed Mahoud of New Bedford. The cows disappeared from the farm Saturday and 40 of them were later found at a Pennsylvania livestock auction.  The other cows were later found at a farm in Medway.