I would request a copy of the village ordinance to see if in fact they are barred. After reviewing the ordinance then you may want to take an appeal or just let the issue die. You would probable need an attorney for the appeal.
I dont think you can appeal if no legal action has occurred. You probably received an opinion letter from the city, which is just that, an opinion. you can kick it upstairs by requesting an opinion from the city attorney, assuming the letter did not arrive from them. If it did, and you have exhausted your city remedies, then your next step may be to file a declaratory action (or the NE equivalent) in the appropriate court asking whether the city is correct. I would follow advice to hire a lawyer if you want to do that. A lawyer could tell you if you have a chance.
Another option is to ask a city councilperson to introduce a change to the city ordinances that allows animals. Many municipalities are now reconsidering their prohibitions against chickens, swine, and milk goats because of hard times.
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