Itoshi no Muco

Kids shows about cute pets. Also, both are animated in CGI. 

Lovely pets, doing funny things. Both speak, although they are not understood by their owners. Heartwarming shows with good comedy. 

Both have Dogs which can be annoying. One is an actual Talking Dog, one has inner monologues you can hear. 

Comedies about the relationships between dogs and humans. Both have dog dialoguing without humans understanding them. 

Comedy about owners and their dogs who love those owners. The dogs also have monologues people can't hear. 

Comedies about a pet trying to make sense of the human world while also doing pet things, i.e., mostly causing trouble. My Roommate Is A Cat has a more dramatic side to it while Lovely Muco is mostly just a comedy. 

Both follow the life of a pet and what silly antics they're up to. 

Both revolve around a pet and their 'family' as they get into silly mischief. Itoshi follows an average dog as it shows the funny interaction, where the dog can understand her owner but he obviously cannot understand her. It is a interesting style of showing what the dog is thinking but showing to her owner she is just a normal dog doing dog things. Dog owners may relate :P. Poyopoyo is a bit weirder, following a round cat and the episodes are usually very random. Both are fairly short episodes, Itoshi being 12 and Poyo being 3 minute episodes.