I think this page is a must read. More case law regarding towns and pet limits.
http://www.animallaw.info/articles/ddusdognumberordinances.htm

Eleanor, have you actually read a copy of your town's dog limit ordinance? Does it state specifically what the ordinance is to protect from? i.e.; if it does, is it for reasons of health & safety, or is it nuisance?
Particularly read section VI. Nuisance Regulation at the above link.

Another eason I suggest too to go get a copy and read it (if you haven't) is from my own experience with a local zoning office. He told me once dgos were livestock and that all my fence setbacks, buildings had to meet those for livestock. I corrected him and told him dogs were domestic animals. He went and looked it up and came back and told me I was right. You'd think someone in a "position" would know their code enforcement, but it's not necessarily the case. Best to do your own research.

What a surprise to me to see the Borough of Danville (Montour County) mentioned also. I have a Danville rural address, but I'm not in the borough.... but interesting to read a little Danville history.
"We do not believe that the borough council or the court has the power or the authority to determine that more than a certain number is a nuisance per se, and less than that number is a nuisance only upon proof of the same being a nuisance. In other words, it is our opinion that the borough council, in the exercise of its police power may not unreasonably and arbitrarily prohibit things which were not nuisances at common law, and their declaration in an ordinance that a thing is a public nuisance does not make it so, if it is not a nuisance in fact . . ."