1. About the withdrawal of quarantine certificates: Recently, the Ministry of Agriculture requested to replace new animal quarantine certificates nationwide, which must be completed before June 1. I think the county sports institute may be taking back the quarantine certificate and replacing it, but before the new one comes, the old one can still be used before June 1. If you apply for inspection, they should quarantine you and issue a certificate.
2. On the issue of 50% fine: According to the Animal Epidemic Prevention Law, if animals without quarantine certificates are transported, a fine of more than 10% and less than 50% will be imposed on the value of similar quarantine-qualified animals. Your 50% is not a quarantine fee, but a fine. According to the maximum penalty, whether the use of discretion is appropriate remains to be discussed.
3. About the seizure of chickens: it should not be seized, but registered and preserved in advance. If it issues a notice of seizure (seizure) instead of a notice of pre-registration and preservation of evidence, it is suspected of violating the administration.
4. How did you solve your loss? First of all, you should be punished for transporting animals without quarantine certificate. It is understandable to treat dead chickens harmlessly, but who will bear your losses is debatable. According to your account, you can file an administrative reconsideration or sue the epidemic prevention station that didn't quarantine you, and they will compensate you for all the losses.
All the above are personal opinions, mainly depending on the evidence. You said you applied for inspection. Do you have any proof? Yes, you can. Please consult a law firm for details.