Narrative:

On push back from the gate in ZZZ aircraft X; I was taking with the tug driver reference the previous flight XXXX from ZZZ2 to ZZZ; which I operated; about the live animal in the forward cargo. That is when the tug driver said that's why they put the dry ice in the aft cargo on flight XXXX. I was not informed of the dry [ice] being put in the aft cargo. If the tug driver had not told me that they off loaded dry ice from my previous flight I would not have known.

Google
 

Original NASA ASRS Text

Title: E-175 flight crew reported being notified that their previously completed flight they unknowingly transported undocumented Dangerous Goods.

Narrative: On push back from the gate in ZZZ Aircraft X; I was taking with the tug driver reference the previous flight XXXX from ZZZ2 to ZZZ; which I operated; about the live animal in the forward cargo. That is when the tug driver said that's why they put the dry ice in the aft cargo on flight XXXX. I was not informed of the dry [ice] being put in the aft cargo. If the tug driver had not told me that they off loaded dry ice from my previous flight I would not have known.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.