i couldnt tell you what it is because there can be many things that might make it smell the way it does. If it were mine i would go and buy as many SPRAY CANS of lysal that you can from your local grocery store and spray that all over the spot thatsmells because it does not ruin the hide if you use that. Make sure you dont get the bottles of lysal because it seems to not work like the spray cans do. If that doesnt work just PM me and i will see what other ways can help you to get ride of the smell