small-breed dog; toy dog
Refers to dogs of small breeds, typically under about 10 kg. Used in pet contexts, breed classifications, and housing rules.
In this apartment, you can only keep small-breed dogs.
Small dogs are easy to keep indoors.
Refers to medium-breed dogs, between small and large. 小型犬 is smaller than 中型犬.
Compound of 小型 (こがた, 'small size') + 犬 (けん, 'dog').