Andre Nortons Star Man's Son , (kallas ibland Daybreak 2250 AD )
Det är postapokalyptiskt, och den ensamma hjälten har en stor kattkompis. Jag läste den först i början av 80-talet, så det kom genast upp i mitt sinne när jag såg din fråga. Den publicerades 1980.
Fors was a mutant. He did not know what drove him to explore the empty lands to the north, where the great skeleton ruins of the old civilization rusted away in the wreckage of mankind's hopes.
But he could not resist the urging that led him through danger and adventure, to the place where he faced the menace of the Star Men.
Two centuries after an atomic war on earth, a silver-haired mutant sets out on a dangerous search for a lost city of the ruined civilization.