Do, you want to change the nature of mosquitoes and dogs? Sometimes you can influence animals, sometimes you can't, it depends. I know that when all the Westerners come up to the Wat during retreats, I don't get bitten as often, because they're bored with me. That's one method, go to a place where there's a lot more people. But if that doesn't work, use a mosquito repellent or try to practice being aware of "unpleasant physical sensations". To develop more patience, compassion and acceptance of their nature, try imagining yourself as a mosquito with all that aversion from so many creatures directed towards you? They're just doing what mosquitoes do, because they want to reproduce. It's pretty strong, isn't it? That desire! They're just trying to reproduce, following their nature.
With dogs, it depends on how they've been trained. The nature of dogs is they are normally territorial. If you interfere or go in their territory and bother them, then they will usually be aggressive. But if you're not threatening, that's one way to do it; and if you don't show fear, that's another way.
I remember an experience of this myself when a friend of ours had a pig dog. This is a very aggressive type of animal. Unfortunately, it became so aggressive he had to keep it in a cage most of the time. One day I happened to just drop by and my friend wasn't there and somehow the dog was out of the cage. However, I had visited often while it was in the cage and wasn't afraid of it. Even though my friend wasn't home and normally dogs are defensive of their territory, I wasn't afraid. As it came up to me, I simply greeted as normal in a friendly tone, "Ooh, hello, how, y'doing?". It jumped up, I petted it and then it just followed me around. Just then, my friend came back and was shocked - first to see the dog out and also to see how meek and mild it was with me. After my friend got the dog back in the cage, his full amazement showed, saying how I could have been ripped apart.
Having had a dog, I was aware that if you show fear to a dog and run away, it can ignite the nature of the hunter in the animal. Try practicing Compassion/Lovingkindness for animals. It may help to lessen fear so if we are near them, you will have a clearer mind unclouded by fear. Sometimes that's the case.
When we lived on a farm, Steve had a part time job substituting for the garbage man. He had to go into people's homes to get the garbage. There was a big German Shepherd dog in one home that came running towards Steve. Instead of high-tailing out of there, Steve turned, faced it and said very strongly, "Go home!" It turned around and went home! So, there're different approaches for different dogs, but I would suggest trying to avoid, i.e. practice the effort to prevent as much as possible, so that you're not in these situations.