petsplain

The pet version of "mansplain"
When a person (who usually has no experience with raising the subject animal) tries to give you unsolicited advice about said animal.

My relative visits my house and sees my (fluffy and definitely not fat) cat.
Relative: He’s too heavy—he needs to lose a few pounds. You need to put him on X/Y diet.
Me: Thank you for petsplaining. I have taken Theodore to the vet and I can assure you he is just fluff.

I finally decide to get a dog after much planning.
Friend: You shouldn't get your dog now.
Me: Why not?
Friend: Well, dogs require a lot of time.
Me: Yes, do you know how much?
Friend: No, but it's a lot.
Me: Well I do know because I have spent a lot of time researching. Thank you for petsplaining and assuming that I will not be a responsible pet owner but I assure you I have more knowledge and determination than you think.