For the 1958 movie, Eisenmann had only one German shepherd, called "London". A second dog, also named "London" was the canine performer for the first, 65-episode television series.
By 1972, Eisenmann's German shepherd complement had increased to seven, with five males: London, Toro, Thorn, Lance, and Litlon; and two females: Venus and Roura.
Eisenmann is shown in the first episode, "Stand-in", of the 1979-85 Littlest Hobo series teaching young Bo, a spry German shepherd with a yellow-gold mane and wide, hypnotic eyes.
Bo was to be a successor to the original London after Eisenmann's incumbent Hobo dog died on the first production day of the 1979-85 Littlest Hobo.
Toro performed the role of the title character in Season 1, with Bo being his "stunt-dog".
For Seasons 2 to 6, Bo was the primary 1979-85 Littlest Hobo, though other German shepherds of similar color markings were used in his stead on some occasions.