The council (I think) public health department should deal with this. The rough guidance is if dogs regularly and frequently make noise for 20 minutes or longer or for shorter times at unsocial hours then it can be a noise nuisance. I am a dog owner and I check with my neighbours about what my dogs do when i am not there.
First step if you can is to talk to your neighbours or drop a note through the door, as bedknobs says, they might not know what the dogs do, although if the people come home at midnight and let the dogs out in the garden and they kick off then then they must know.
The council will assess the situation, maybe leave you with monitoring equipment , and deal with any nuisance if they find one. Owners can be prosecuted and fined and council or social housing tenants can also be evicted.
It can be worth keeping your on noise diary before approaching the council.
There should be more information on your council's website.
if you play loud music, have noisy kids or enjoy noisy DIY, or otherwise indulge in any unsocial activities yourself, you may want to think twice about complaining.