This is, of course, the etymological basis for the word thank you in many Slavic languages (at least a twitchen, at last count), as DeSelby points out in his all-encompassing magnum opus "de linguis selvajes, slavajes, y salvajes", uniting in one dense philological tome his musings on the woodland chirping languages of the Amazonian Reese tribes, the "bun-yip" based dialects of the native Kylie indigenous people of the Didgeridoo region of the inner gully of the brokeback dingo valley of the wallabillbe suburb of Adelaide, and the unique patois of Ivana Trump.
The špas in špas-ibo means fun. Ibo, of course, is well-known to have been princess Nefertitti's pet name for the Emperor Augustus, giving us Fun-gus. Or equivalently Mush-room. This, of course is a clear reference to the original Iditarod canine hero, Togo (memorialized each time someone orders a pizza togo, and never mind the statue of the filthy limelight-hogging Balto). Obviously all those diphtheria-ridden Alaskan babies were very grateful to receive that serum, from whence which we have the derivation špas-ibo, meaning "thanks, I'll have my serum to go please".