Father also included bear (5)
I believe the answer is:
Here is my best explanation:
'bear' is the definition.
'father also included' is the subsidiary indication.
'father' becomes 'pa' (pa is a kind of father).
'also' becomes 'and' (I've seen this before).
'included' means one lot of letters goes inside another.
'pa' placed around 'and' is 'panda'.
(Other definitions for panda that I've seen before include "Asian animal", "Bearlike animal", "Endangered bamboo eater", "Large black-and-white herbivorous mammal", "Giant, red, Chinese mammal", "Mammal, giant or red", "Police car", "Endangered black and white species", "Bamboo-eater" and "Black and white animal".)