I ran into a small essay on The Internet about how keeping domesticated animals as house pets is ethically murky. After all, the dog or the cat is stuck in your house, they literally depend upon you for their survival -- their life is kind of a gilded cage, yeah?
I think where the problem comes from is that, for cats and dogs at least, they weren't domesticated as house pets. They were domesticated as primarily-outdoor work animals...or more accurately, they kind of domesticated themselves as outdoor work animals. Dogs became dogs when certain brave and friendly wolves started eating scraps from human garbage piles, and then got closer and started working with humans for hunting. Cats moved into human grain barns to find a ready source of tasty rodents, and stayed there ever since.
For most of the history of their relationship with humans, cats and dogs have not strictly relied upon us for everything. They could get some of their own food, go where they would to a certain degree, and then come home where the easy food was. They weren't stuck in gilded cages like they are now. You can see this sort of human-dog relationship if you go to Bali, where the Balinese Street Dogs run free around the island but protect their chosen families fiercely.
It is only recently in The West that the work purpose of dogs has been forgotten in favor of making them purely companions. I do not think this is fair to a dog, especially if it is of a pure breed that was designed to excel at one specific task, to the detriment of all other tasks -- refusing to let such a dog actually perform that task is kind of mean. Would you have a Dalmatian and never give it a carriage to run beside? Or a Siberian Husky and never give it a sled to pull or snow to play in? Yet people do so all the time.
And yet -- what else can you do with a dog? So many of the jobs dogs once had were supersded by machines. We don't need them for work as much as we used to. But we still want our dogs.
I think the answer is that, if you're going to have a dog, you should only get a pure breed if you need it for a specific purpose; otherwise, get a mutt. And if it's a big dog, you should hve a big yard. Big dogs are not meant to be cooped up. They need space to run. They need space to romp. If you have a small house you should get a small mutt, if you even want to put a dog in a house like that.
As for cats, well, they can handle themselves, as ever.
As for parrots -- oh my god no do not get a parrot unless you want to be its constant companion and swap out its toys constantly. Parrots are even smarter than dogs. If you don't keep them entertained they will go absolutely nuts from boredom. Parrots aren't domesticated. Why are you keeping a parrot. What are you doing.