Few of the possible solutions:
If the Source application is ok, you can have them but a sort of Trailer message at the end of their batch messages...which will have the total count. And of course hav ...
Undoubtedly this is an old question but I have not been able to locate any info. I'm curious about any common patterns/implementations for handling 'batches" of messages.
I recently had to do some work with dead letter messages so was using using the MQDEAD tab if MQVE. I saw a couple of things there that are inconsistent with the way some fields are handled on the MQM ...