With Bug and Dragon being types there's no reason Dog shouldn't be a type too

Growlithe, Arcanine - Fire / Dog
Snubbul, Granbull - Dog / Fairy
Houndour, Houndoom - Dark / Dog
Smeargle - Normal / Dog
Poochyena, Mightyena - Dog / Dark
Electrike, Manectric - Electric / Dog
Riolu - Fighting / Dog (Lucario drops Dog type)
Cherubi, Cherrim – Grass / Dog
Lillipup, Herdier, Stoutland - Normal / Dog
Furfrou - Dog
Slurpuff – Fairy / Dog (Swirlix remains pure Fairy)
Rockruff, Lycanroc - Dog / Rock
Yamper, Boltund - Dog / Electric
Zacian - Fairy / Dog
Zamazenta - Fighting / Dog
Hisuian Growlithe, Arcanine - Rock / Dog
Fidough - Fairy / Dog
Greavard - Ghost / Dog

Then you would have pokémon like Vulpix, Eevee, Suicune, Zigzagoon, Zorua, Popplio, etc that despite not being Dog type would still learn a fair share of Dog type moves.