Design for mutiConsumer System

My System will receive feeds from 40 other Systems in future. At present its taking feed from 2 systems. We are using factory design pattern to handle the processing of various feeds. Eventually in this approach I will be having 40 classes and a huge chain of if-else blocks. I personally do not think this is a good design. Can any one sight me an alternative design to this ? What design pattern can be thought of to make a robust and strategic design to cater to such requirements.

Thanks Anirban Banerjee