It sounds like you already know the answers to your own questions. You know the Constitution better than most lawyers, so why bother asking us for an answer?
The fact of the matter is your question is too multifaceted to be amenable to answering in this circumstance. If you want a detailed answer to all of this, I suggest you consult with a Constitutional law expert and get your answers.
Sounds like you've had certain animals confiscated without due process of law. Obviously, the Constitutional rights of which you speak exist even in a court without a record, despite what some Justice of the Peace says.
I agree with my colleague - there is simply no way to answer your question without a complete review of the facts and all the documents, vet records, evidence, and court records in the case. Your local bar association (either the Texas Bar or the Dallas Bar) should be able to refer you to an attorney.