Man made tiger piss thats somthing new to me but i guess it would work but if you got kangaroos im not sure the smell will scare them away if theyve never smelled tigers piss before i dont know if kangaroos and tigers live in the same area though whatever. What i would do is buy some chicken wire chicken wire will keep small animals away from your plants stems like rabbits and shit just put up a small circle around your crop. And to keep away bigger animals put up another circle of fence about 12 inches from the other and hook barb wire onto it. I had said to put up two circles because a lager animal will usually knock down the part of the fence with the barb wire but it wont be coming back for a while anyway after getting cut but while thats knocked down a smaller animal would be able to crwal over or around it so the second is to stop the little animals from coming after the big ones. barb is surprisingly easy to come across but sounds like you live in a place way different than me. If you cant get barb wire you could cut down thorn bushes and wrap them around the chicken wire. chicken wire is almost free thorn bsuhes and brab wire come free.