Errors when deleting an animal from the mouse database

[annkennedy]

If I delete a mouse that has trials associated with it, Bento gives the user an option to assign those trials to a different animal by selecting that animal from a drop-down menu. That dropdown menu does not populate, and the terminal gives the following error:

Exception in populateComboBox: 'Animal' object has no attribute 'animal_id'

this suggests that the combo box is looking for an animal_id attribute that we got rid of?