[dns-wg] How to determine the last message in sequence in DNS TCP responce

I make DNS zone transfer request (aka AXFR) via TCP to the server. The answer is too big (>100Kb), so it could not be sent in one TCP message. So the server send me a sequence of messages. How can I determine which message is the last? I can't found anything about it's count in the first message. I can't found any special flag in the last one. I can't found anything about it in RFC1035. Could you please explain how to find "end of answer"?