Yeah, those npk readings blew me away. But I can't seem to find anyone that has those castings
honestly man, I think the NPK is not correct.
I'm fairly certain no pig could make manure that rich.
The reason birds can is because they mix their urine and guano together (no separate digestive area)
I did find a research noting the NPK levels, and it was similar to the numbers you posted, but it wasn't a %, it was per hectare.
everything that I know about manure says otherwise, but I could be wrong