Dag is very similar to:

Scar: They have both killed a clan leader that happened to be the protagonist (Simba and Otis)'s father (Mufasa and Ben), they knew said leader from the past and they have a scar on their eye. As well, they did the same thing to the protagonist that they have to kill their respective fathers: Scar jugged his claws on Mufasa and Simba's paws and Dag bit Ben and Otis's leg. And not only that, but they are also complete monsters, and rather scrawny compared to the other characters in their movies, are leaders of a pack (Scar being the boss of the hyenas and Dag being the boss of his pack), were ordered by the protagonist to never return after they were defeated by them.

Black Wolf: As both of them are complete monsters, canine villains, and totally bent on the destruction of animals, only in Dag's case, it's the animals and The Farmer whereas in Black Wolf's case, it's the reindeer and Santa. They are also both the leaders of their packs.

Shere-Khan 2016: Both are evil predatory animals (Dag being a coyote and Shere-Khan being a tiger) who have scars on their faces and killed the protagonist's father and are later defeated by the protagonist, are the former leaders of a pack of canines (Dag being the former boss of his pack and Shere-Khan being the former boss of the wolves after his murder of Akela). Additionally, The Jungle Book: 2016 came out 10 years later after barnyard.

Koba: Both are animals (Coyote/Bonobo ape) who have scars on their faces, are complete monsters, and they try to kill a clan leader (Casear/Ben), however, Dag actually succeeded, but was defeated by his foster son and successor, Otis).

Sabor: Both are predatory animals (Coyote/Leopard) who killed the protagonist's parents and are later defeated by the protagonists and thus the parents they killed are avenged.