Remember, I lived in the city for much of my adult life so sorry if this is a silly question. But - is there any reason to use the bagged manure you buy in the store over a fresh cow patty? We got a few cows, it seems silly to buy manure, but someone told me that there could be parasites or something in the cow patty that will hurt my garden. That just didn't make sense to me but I don't know for sure.