Bitzer the dog's wristwatch vanishes whenever he goes on four legs.
Although not explicitly or even commonly mentioned, the Sheep flock are likely from the Suffolk breed due to their black head and legs.
Shaun the Sheep is a spin off of Wallace and Gromit and has a spin-off called Timmy Time about Timmy. Shaun's first appearance was in A Close Shave from Wallace and Gromit.
In the second season, Bitzer (the yellow sheep dog with a blue cap) had white fur on his belly and muzzle. He reverted back to his yellow coloring in the third season and his appearance was not changed again in the later seasons.
The theme song is sung by British comedian Vic Reeves.