Full Idea
It appears probable that animals have souls although they lack consciousness.
Gist of Idea
Animals have souls, but lack consciousness
Source
Gottfried Leibniz (Letters to Antoine Arnauld [1686], 1686.11)
Book Reference
Leibniz,Gottfried: 'The Leibniz-Arnauld Correspondence', ed/tr. Mason,HT/Parkinson,GHR [Manchester UP 1967], p.90
A Reaction
Personally I would say that they lack souls but have consciousness, but then I am in no better position to know the answer than Leibniz was. Arnauld asks what would happen to the souls of 100,000 silkworms if they caught fire!