As such, this is a very interesting dream.
There are several situations that are significant for interpretation: (1) The small animals are likeable animals like chickens, kittens, puppies, piglets, calves, kids, etc. (2) The small animals are disliked and unpleasant like rats and baby snakes.
The feeling of the dreamer is also important. The dreamer may feel sad seeing the small animals going stiff. The dreamer may feel safe seeing the small animals going stiff. The dreamer may feel relieved seeing the small animals going stiff.
In Chinese dream interpretations, snakes represent the “affairs of the netherworld.” I would interpret the snakes as representing deep down worries of the dreamer. Thus seeing baby snakes going stiff would mean that personal worries are now no longer worries. The same interpretation could be applied to the meaning of seeing small rats going stiff. This may indicate that the dreamer’s fears and worries are gone.
Seeing likeable small animals die evokes sympathy, sadness and a sense of loss. The small animals may symbolize an aggregate of good and enjoyable qualities of a friend and the many pleasant moments the dreamer had shared with the dear friend who has passed on. This could be a dream of one who has just lost a dear friend in a fatal automobile accident.