I have made an exit on a sow, but she is not dead, can I delete the exit?

Yes. Select the tab “Sows/boars” – “Animal” - “PigVision” – “Removed animals”. 

Using the filter line, you can find the sow: Here 1289

Put the curser in the field “Exit – date” and press Shift + Delete. You will get this picture on your screen. 

Confirm and the sow is alive.