Where did Polly bring his pet dog to?

Mrs. Banks is talking to Polly, a young schoolboy. Mrs. Banks and Polly are talking about pets.
Mrs. Banks: Good morning, Polly. I haven’t seen you for a few months. I expect you’ve been busy at school.
Polly: Yes, I have, Mrs. Banks, but today I have a holiday.
Mrs. Banks: I see you have your dog with yon. Have you just taken him for a walk?
Polly: No, I’ve been to the vet with him.
Mrs. Banks: What’s the trouble?
Polly: Nothing serious. He is still a puppy and he needed his anti-rabies injection.
Mrs. Banks: I’m glad to see that you keep him on a lead. Many people allow their dogs to run around without even a collar on, and then they can easily be mistaken for stray dogs.
Polly: My mother says that if you have a pet you should look after it well.
Mrs. Banks: That’s quite true. I see yours is well cared for. His coat is shiny and he is in very good condition.
Polly: I brush and comb him every day. I start with his back and then I do his tail. I also have to look at his paws often as he sometimes gets an infection in one of his front paws.
Mrs. Banks: Does he bark much?
Polly: Only when strangers come to the front door. He is a good watchdog.
Mrs. Banks: What do you give him to eat and drink?
Polly: He drinks water and eats meat mostly but we often give him other bits and pieces for a change. He enjoys a nice bone but my mother says that he makes a mess of that.
Mrs. Banks: You know, in many parts of the world, dogs do important work.
Polly: I didn’t realize that, Mrs. Banks.
Mrs. Banks: In Switzerland, big dogs are trained to save people lost in the mountains and they also bring help to injured people.
Polly: What else do dogs do?
Mrs. Banks: Well, in Iceland, dogs pull sledges over the snow and they are very important there.
Polly: In Hong Kong, we have police dogs, don’t we?
Mrs. Banks: That is another thing that dogs are used for. They help the police a great deal and they are also used in the Army and Air Force for the same purpose.
Polly: My teacher told me that dogs are often called "Man’s best friend".
Mrs. Banks: That’s quite true in most cases, but some dogs can be quite dangerous.
Polly: My brother was bitten by a dog last year and now he is afraid of them.
Mrs. Banks: He has a cat, hasn’t he?
Polly: Yes, he was given that for his birthday when it was a kitten.
Mrs. Banks: I hope he looks after it.
Polly: He does. He gives it milk and fish and when he hears it mew and purr he says that it is talking to him.
Mrs. Banks: Your mother told me that it catches rats and mice so it is useful. Have you any more pets at home?
Polly: We have two birds in a big cage. One has blue feathers and the other has yellow feathers so they look pretty together.
Mrs. Banks: When I was a little girl my father had a big aviary in the garden with ail different kinds of birds in it. I used to love watching them flying around.
Polly: It must have taken a lot of seed to feed them all.
Mrs. Banks: It did, but my father made the birds his hobby so he didn’t mind at all.
Polly: Our two birds sit on their perch and peck at each other with their beaks and they seem to talk to each other.
Mrs. Banks: One of my father’s birds was a parrot and he really did talk. If I asked him his name, he answered by saying, "I’m Polly". He also said, "Time for tea".
Polly: He must have been funny, especially as his name was the same as mine.
Mrs. Banks: He was and all the children of the neighborhood loved him. My father also had a tortoise.
Polly: My friend has one too but he is not very interesting as he doesn’t do very much except sleep. I like my friend’s fish the best.
Mrs. Banks: Does she keep them in a bowl or a tank?
Polly: Neither. She has them in a small pond in the garden and when she goes to the side of the pond they come up to be fed so they are really quite tame.
Mrs. Banks: A friend of mine had a pet goat when she was young and her next-door neighbor had a pet lamb.
Polly: I don’t think they would make very nice pets.
Mrs. Banks: They are all right if you have a big garden to keep them in. Another girl I knew had a pony and I always envied her.
Polly: Some of my classmates have white mice and hamsters and one boy has a pet guinea pig.
Mrs. Banks: I don’t like that kind of pet very much but I know they are quite popular.
Polly: I still think my dog is the best pet.
Mrs. Banks: The main thing is for each person to be happy with his or her own pet.
Polly: I like my dog and my brother likes his cat.
Mrs. Banks: That way, you are both happy.