We moved into our subdivison 1 1/2 years ago we have two horses which is fine according to our current covenants. We can have as many as 3 on one lot, we also clean up after them every day and have a garbage company that comes and picks up the manure out of a dumpster once a week. This is also in accordance to the covenants that states it has to be hauled off or buried. My question is that recently many people have decided to change the covenants to make it so people can not bring any horses, and once ours died that we could not replace them. Is there some form of grandfather clause so that when my horses do pass on I could replace them? We just built a huge indoor riding area and this is going to be a complete waste of money if we can't have more! Thank you for any advice!!

This sounds like HOA rules, not actual zoning laws. I do not believe they can change the rules as long as you contineu to have animals on that property, but it will end up in a court of law, so you may as well get the attorney now.

If you think this is more than a rumor, you need to consult an attorney now and try to get some facts. In my area, there aren't a lot of attorneys who specialize in HOA situations.
Laws vary greatly by state and probably even county. I was on an HOA board in WV and although the board had input into the wording of the covenants, the final covenants had to be ruled on for constitutionality, then approved and signed by a judge. Revising those covenants was a long and costly process. If your board is subject to similar rules, they may have a different opinion about making changes, and the sooner you let them know the less likely it is to be pursued.

You need to consult an attorney. If the HOA follows their by-laws in amending the covenants there may be little you can do about it.

I'm wondering if the construction of the indoor riding area may have set some neighbors off. Did you get the required approvals for constructing this area?

If the HOA approved this construction and then goes and passes an amendment to not allow any new horses, you might have a suit against them.

Yes we have the architectural committee approval letter, along with the city and state permits.